MAXIM DS1886T+T

19-6259; Rev 1; 8/12
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
General Description
The DS1886 controls and monitors all functions for SFF,
SFP, and SFP+ modules including all SFF-8472 functionality for GPON/EPON and 10G PON ONU applications. The combination of the DS1886 with the MAX3710
supports all transmitter and receiver functionality. The
DS1886 includes modulation current control and APC setpoint control with tracking error adjustment. It continually
monitors RSSI for LOS generation. A 13-bit analog-todigital converter (ADC) monitors VCC, temperature, laser
bias, laser modulation, and receive power to meet all
monitoring requirements. Receive power measurement
is differential with support for common mode to VCC. A
9-bit digital-to-analog converter (DAC) is included with
temperature compensation for APD bias control.
Applications
SFF, SFP, and PON ONU Modules
Ordering Information appears at end of data sheet.
Features
SMeets All SFF-8472 Control and Monitoring
Requirements
SCompanion Controller for the MAX3710 Laser
Driver/Limiting Amplifier and MAX3945 Limiting
Amplifier
SMAX3710/DS1886 Combination Supports
Broad Spectrum of Continuous Mode and PON
Applications Up to 2.5GHz
STemperature Lookup Table (LUT) to Compensate
for APC Tracking Error and Dual Closed-Loop
Variables
SThree Laser Control Modes
Dual Closed Loop: Laser Bias and Laser
Modulation Are Automatically Controlled with
Multiple LUTs to Compensate Dual Closed-Loop
Calibration Points
APC Loop: Laser Bias Automatically Controlled,
Laser Modulation Controlled by Temperature LUT
Open Loop: Laser Bias and Laser Modulation
Are Controlled by Temperature LUTs
S13-Bit ADC
Laser Bias, Laser Power, and Receive Power
Support Internal and External Calibration
Differential Receive Power Input
Scalable Dynamic Range
Internal Direct-to-Digital Temperature Sensor
Alarm and Warning Flags for All Monitored
Channels
S10-Bit DAC with Temperature Compensation for
APD Bias
SDigital I/O Pins: Transmit Disable Input/Output,
Rate Select Input, LOS Input/Output, Transmit
Fault Input/Output, and IN1 Status Monitor and
Fault input
SComprehensive Fault Measurement System with
Maskable Alarm/Warnings
SFlexible Password Scheme Provides Three Levels
of Security
S256-Byte A0h and 128-Byte Upper A2h EEPROM
SI2C-Compatible Interface
S3-Wire Master to Communicate with the MAX3710/
MAX3711 Laser Driver/Limiting Amplifier and
MAX3945 Limiting Amplifier
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
TABLE OF CONTENTS
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
DAC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Analog Voltage Monitoring Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Digital Thermometer Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
AC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Startup Timing Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3-Wire Digital Interface Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
I2C AC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Nonvolatile Memory Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Typical Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Typical Operating Circuit—GPON ONU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Typical Operating Circuit—10G PON ONU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Monitors and Fault Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
ADC Monitors and Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Alarms and Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
ADC Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Right-Shifting ADC Result . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Differential RSSI Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Laser Bias and Laser Power Through TXMON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Enhanced RSSI Monitoring (Dual Range Functionality) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
APD Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
PIN Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Low-Voltage Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Power-On Analog (POA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Delta-Sigma Output and Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Digital I/O Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
TABLE OF CONTENTS (continued)
LOS, LOSOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
RSEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
TXD, TXDOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
IN1, TXF, Transmit Fault (TXFOUT) Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Die Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
DS1886 Master Communication Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3-Wire Master Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3-Wire Slave Register Map and DS1886 Corresponding Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3-Wire Master Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3-Wire Power-On Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
DS1886 with MAX3710 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Open Loop Mode, DPC_EN = 0, APC_EN = 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
APC Loop Mode, DPC_EN = 0, APC_EN = 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Dual Closed-Loop Mode, DPC_EN = 1, APC_EN = 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
BIAS, MODULATION, SET_2XAPC, TXCTRL5 LUTs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
MODULATION Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
BIAS Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Power Leveling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Manual MAX3710 Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
I2C Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
I2C Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
I2C Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Memory Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
A2h Lower Memory Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
A2h Table 01h Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
A2h Table 02h Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
A2h Table 04h Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
A2h Table 05h Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
A2h Table 06h Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
A2h Table 08h Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
A2h Table 09h Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Auxiliary A0h Memory Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
A2h Lower Memory Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
A2h Lower Memory, Register 00h–01h: TEMP ALARM HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
3
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
TABLE OF CONTENTS (continued)
A2h Lower Memory, Register 04h–05h: TEMP WARN HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
A2h Lower Memory, Register 02h–03h: TEMP ALARM LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
A2h Lower Memory, Register 06h–07h: TEMP WARN LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
A2h Lower Memory, Register 08h–09h: VCC ALARM HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 0Ch–0Dh: VCC WARN HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 10h–11h: TXB ALARM HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 14h–15h: TXB WARN HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 18h–19h: TXP ALARM HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 1Ch–1Dh: TXP WARN HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 20h–21h: RSSI ALARM HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 24h–25h: RSSI WARN HI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A2h Lower Memory, Register 0Ah–0Bh: VCC ALARM LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 0Eh–0Fh: VCC WARN LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 12h–13h: TXB ALARM LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 16h–17h: TXB WARN LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 1Ah–1Bh: TXP ALARM LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 1Eh–1Fh: TXP WARN LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 22h–23h: RSSI ALARM LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 26h–27h: RSSI WARN LO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A2h Lower Memory, Register 28h–37h: EMPTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
A2h Lower Memory, Register 38h–5Fh: EE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
A2h Lower Memory, Register 60h–61h: TEMP VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
A2h Lower Memory, Register 62h–63h: VCC VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
A2h Lower Memory, Register 64h–65h: TXB VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
A2h Lower Memory, Register 66h–67h: TXP VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
A2h Lower Memory, Register 68h–69h: RSSI VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
A2h Lower Memory, Register 6Ah–6Dh: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
A2h Lower Memory, Register 6Eh: STATUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
A2h Lower Memory, Register 6Fh: UPDATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
A2h Lower Memory, Register 70h: ALARM3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
A2h Lower Memory, Register 71h: ALARM2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
A2h Lower Memory, Register 72h–73h: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
A2h Lower Memory, Register 74h: WARN3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
A2h Lower Memory, Register 75h: WARN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
A2h Lower Memory, Register 76h–7Ah: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
4
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
TABLE OF CONTENTS (continued)
A2h Lower Memory, Register 7Bh–7Eh: PASSWORD ENTRY (PWE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
A2h Lower Memory, Register 7Fh: TBL SEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
A2h Table 01h Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A2h Table 01h, Register 80h–BFh: EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A2h Table 01h, Register C0h–F7h: EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
A2h Table 01h, Register F8h: ALARM EN3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A2h Table 01h, Register F9h: ALARM EN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
A2h Table 01h, Register FAh–FBh: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
A2h Table 01h, Register FCh: WARN EN3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
A2h Table 01h, Register FDh: WARN EN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
A2h Table 01h, Register FEh–FFh: RESERVED OR EE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
A2h Table 02h Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
A2h Table 02h, Register 80h: MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
A2h Table 02h, Register 81h: Temperature Index (TINDEX) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
A2h Table 02h, Register 82h–83h: MODULATION VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
A2h Table 02h, Register 84h: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
A2h Table 02h, Register 85h: APC VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
A2h Table 02h, Register 86h–87h: SET_IBIAS VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
A2h Table 02h, Register 88h: DACFS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
A2h Table 02h, Register 89h: CNFGA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
A2h Table 02h, Register 8Ah: CNFGB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
A2h Table 02h, Register 8Bh: CNFGC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
A2h Table 02h, Register 8Ch: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
A2h Table 02h, Register 8Dh: CNFGD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
A2h Table 02h, Register 8Eh: RIGHT-SHIFT1 (RSHIFT1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
A2h Table 02h, Register 8Fh: RIGHT-SHIFT0 (RSHIFT0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
A2h Table 02h, Register 90h–91h: XOVER COARSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
A2h Table 02h, Register 92h–93h: VCC SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
A2h Table 02h, Register 94h–95h: TXB SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
A2h Table 02h, Register 96h–97h: TXP SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
A2h Table 02h, Register 98h–99h: RSSI FINE SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
A2h Table 02h, Register 9Ah–9Bh: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
A2h Table 02h, Register 9Ch–9Dh: RSSI COARSE SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
A2h Table 02h, Register 9Eh–9Fh: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
A2h Table 02h, Register A0h–A1h: XOVER FINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
A2h Table 02h, Register A2h–A3h: VCC OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
5
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
TABLE OF CONTENTS (continued)
A2h Table 02h, Register A4h–A5h: TXB OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
A2h Table 02h, Register A6h–A7h: TXP OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
A2h Table 02h, Register A8h–A9h: RSSI FINE OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
A2h Table 02h, Register AAh–ABh: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
A2h Table 02h, Register ACh–ADh: RSSI COARSE OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
A2h Table 02h, Register AEh–AFh: INTERNAL TEMP OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
A2h Table 02h, Register B0h–B3h: PW1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
A2h Table 02h, Register B4h–B7h: PW2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
A2h Table 02h, Register B8h–BFh: EMPTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
A2h Table 02h, Register C0h: PW_ENA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
A2h Table 02h, Register C1h: PW_ENB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
A2h Table 02h, Register C2h–C6h: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
A2h Table 02h, Register C7h: TBLSELPON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
A2h Table 02h, Register C8h–C9h: DAC VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
A2h Table 02h, Register CAh: INCBYTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
A2h Table 02h, Register CBh: TXCTRL5 DPC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
A2h Table 02h, Register CCh: IMODMAX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
A2h Table 02h, Register CDh: IBIASMAX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
A2h Table 02h, Register CEh: DEVICE ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
A2h Table 02h, Register CFh: DEVICE VER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
A2h Table 02h, Register D0h–DFh: EMPTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
A2h Table 02h, Register E0h: RXCTRL1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
A2h Table 02h, Register E1h: RXCTRL2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
A2h Table 02h, Register E2h: SETCML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
A2h Table 02h, Register E3h: SETLOSH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
A2h Table 02h, Register E4h: TXCTRL1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
A2h Table 02h, Register E5h: TXCTRL2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
A2h Table 02h, Register E6h: TXCTRL3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
A2h Table 02h, Register E7h: TXCTRL4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
A2h Table 02h, Register E8h: TXCTRL5 APC OL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
A2h Table 02h, Register E9h: TXCTRL6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
A2h Table 02h, Register EAh: TXCTRL7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
A2h Table 02h, Register EBh: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
A2h Table 02h, Register ECh: SETLOSH_3945 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
A2h Table 02h, Register EDh: SETLOSL_3945 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
A2h Table 02h, Register EEh: SETLOSTIMER_3945 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
6
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
TABLE OF CONTENTS (continued)
A2h Table 02h, Register EFh: 3WSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
A2h Table 02h, Register F0h: 3WCTRL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
A2h Table 02h, Register F1h: ADDRESS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
A2h Table 02h, Register F2h: WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
A2h Table 02h, Register F3h: READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
A2h Table 02h, Register F4h: TXSTAT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
A2h Table 02h, Register F5h: TXSTAT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
A2h Table 02h, Register F6h: DPCSTAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
A2h Table 02h, Register F7h: RXSTAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
A2h Table 02h, Register F8h–FFh: RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
A2h Table 04h Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
A2h Table 04h, Register 80h–A7h: MODULATION or TXCTRL5 LUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
A2h Table 04h, Register A8h–EFh: EMPTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
A2h Table 04h, Register F0h–F7h: MOD MAX LUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
A2h Table 04h, Register F8h–FFh: MOD OFFSET or SET_IMOD LUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
A2h Table 06h Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
A2h Table 06h, Register 80h–A7h: BIAS or SET_IBIAS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
A2h Table 06h, Register A8h–EFh: EMPTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
A2h Table 06h, Register F0h–F7h: BIAS MAX LUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
A2h Table 06h, Register F8h–FFh: BIAS OFFSET or APC LUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
A2h Table 08h Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
A2h Table 08h, Register 80h–F7h: EMPTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
A2h Table 08h, Register F8h–FFh: INCBYTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
A2h Table 09h Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
A2h Table 09h, Register 80h–F7h: EMPTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
A2h Table 09h, Register F8h–FFh: DAC OFFSET LUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Auxiliary Memory A0h Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Auxiliary Memory A0h, Register 00h–FFh: EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Power-Supply Decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Layout Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
SDA and SCL Pullup Resistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
7
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
LIST OF FIGURES
Figure 1a. ADC Channel Only for TXP when BURST_MODE = 1 in Table 02h, Register 89h . . . . . . . . . . . . . . . . . . . 19
Figure 1b. ADC Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 2. ADC Round-Robin Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 3. RSSI Differential Input for High-Side RSSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 4. Laser Bias (TXB) and Laser Power (TXP) Monitoring Through TXMON . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 5. RSSI in APD Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 6. RSSI in PIN Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 7. Low-Voltage Hysteresis Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 9. Delta-Sigma Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Figure 8. Recommended Shunt Reference and RC Filter for DAC Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Figure 10. TXFOUT and TXDOUT Logic Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Figure 11. RSEL Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Figure 12a. TXFOUT Nonlatched Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 12b. TXFOUT Latched . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 12c. TXFOUT During Power-On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 13. 3-Wire Interface Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 14. 3-Wire Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Figure 15. MAX3710 Brownout Detection Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 16. Offset LUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 17. MODULATION LUT (Open Loop and APC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 18. BIAS LUT (Open Loop) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 19. I2C Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Figure 20. Example I2C Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Figure 21. Memory Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
8
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
LIST OF TABLES
Table 1. Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 2. ADC Default Monitor Full-Scale Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 3. RSSI Hysteresis Threshold Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 4. RSSI Configuration Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 5. 3-Wire Transaction Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Table 6. 3-Wire Register Map and DS1886 Corresponding Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 7. DS1886 LUT Functions in Open Loop, APC Loop, and Dual Closed-Loop Modes . . . . . . . . . . . . . . . . . . . . 32
Table 8. DS1886 LUT Memory Map for 5-Row Table (Temperature Values Indicated in °C) . . . . . . . . . . . . . . . . . . . . . . . 33
Table 9. DS1886 LUT Memory Map for 5-Row Table (TINDEX Values Indicated in Hex) . . . . . . . . . . . . . . . . . . . . . . 33
Table 10. Temperature Resolution for Offsets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Table 11a. Power Leveling Details (when DS1863_MODE = 0, default) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Table 11b. Power Leveling Details (when DS1863_MODE = 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
9
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
ABSOLUTE MAXIMUM RATINGS
(All voltages relative to ground.)
Voltage Range on IN1, DAC, LOS, RSSIP, RSSIN,
REFIN, RSEL, TXF, TXMON, TXD.......... -0.5V to (VCC + 0.5V)
(subject to not exceeding +6V)
Voltage Range on VCC, SDA, SCL, TXFOUT
and LOSOUT........................................................-0.5V to +6V
Continuous Power Dissipation (TA = +70NC)
TQFN (derate 28.6mW/NC above +70NC)................2285.7mW
Operating Temperature Range........................... -40NC to +95NC
Programming Temperature Range........................ 0NC to +95NC
Storage Temperature Range............................. -55NC to +125NC
Lead Temperature (soldering, 10s).................................+300NC
Soldering Temperature (reflow).......................................+260NC
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
(TA = -40NC to +95NC, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
(Note 2)
MIN
TYP
MAX
UNITS
2.97
3.63
V
Main Supply Voltage
VCC
High-Level Input Voltage
(SDA, SCL, SDAOUT)
VIH:1
0.7 x
VCC
VCC +
0.3
V
Low-Level Input Voltage
(SDA, SCL, SDAOUT)
VIL:1
-0.3
+0.3 x
VCC
V
High-Level Input Voltage
(IN1, LOS, RSEL, TXD, TXF)
VIH:2
2.0
VCC +
0.3
V
Low-Level Input Voltage
(IN1, LOS, RSEL, TXD, TXF)
VIL:2
-0.3
+0.8
V
TYP
MAX
UNITS
0.7
2
mA
1
FA
DC ELECTRICAL CHARACTERISTICS
(VCC = +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
Supply Current
ICC
Output Leakage
(LOSOUT, SDA, SDAOUT,
TXFOUT)
ILO
Low-Level Output Voltage
(CSEL1OUT, CSEL2OUT,
LOSOUT, SDA, SDAOUT,
SCLOUT, TXDOUT, TXFOUT)
VOL
High-Level Output Voltage
(CSEL1OUT, CSEL2OUT,
SCLOUT, SDAOUT, TXDOUT)
VOH
Input Leakage Current
(IN1, LOS, RSEL, SCL, TXD, TXF)
CONDITIONS
MIN
(Notes 2, 3)
IOL = 4mA
0.4
V
IOL = 6mA
IOH = 4mA
0.6
VCC 0.4
ILI
Digital Power-On Reset
POD
Analog Power-On Reset
POA
POA > POD by design
V
1
FA
1.6
2.6
V
2.2
2.8
V
10
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
DAC ELECTRICAL CHARACTERISTICS
(VCC = +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted.) (Note 1)
PARAMETER
Delta-Sigma Input Clock
Frequency
Reference Voltage Input (REFIN)
SYMBOL
CONDITIONS
fDS
VREFIN
Minimum 0.1µF to GND
RDS
tINIT_DAC
MAX
MHz
VCC
V
0
VREFIN
V
10
Bits
100
I
See the Startup Timing
Characteristics table
ms
VREFIN = 2.5V
45
From VCC > VCC LO alarm or warning
UNITS
2
See the Delta-Sigma Output and Reference
section for details (DAC FS[9:2] = FFh)
Output Resolution
Recovery After Power-Up
TYP
2.1
Output Range
Output Impedance
MIN
ANALOG VOLTAGE MONITORING CHARACTERISTICS
(VCC = +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
ADC Resolution
(Note 4)
INL
TA = +25NC
tRR
Update Rate for RSSIP-RSSIN
Input/Supply Offset (TXMON,
RSSIP, RSSIN, VCC)
TYP
MAX
UNITS
-3
+3
LSB
-1
+1
LSB
13
DNL
Update Rate for Temperature,
TXMON (TXB/TXP),
RSSIP-RSSIN, VCC
MIN
Bits
RSSIP-RSSIN requires only a coarse
conversion (Note 5)
30
ms
tR/R2
RSSIP-RSSIN requires a fine conversion
36
ms
VOS
(Notes 5, 6)
-1
TXMON and RSSIP-RSSIN coarse
(Notes 6, 7)
Factory Setting Full Scale
0
+1
2.5
LSB
V
VCC (Note 7)
6.5536
RSSIP-RSSIN fine (Note 7)
312.5
µV
1/256
NC
Temperature LSB Weighting
DIGITAL THERMOMETER CHARACTERISTICS
(VCC = +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted.) (Note 1)
PARAMETER
Thermometer Error
SYMBOL
TERR
CONDITIONS
-40NC to +95NC, guaranteed by design
MIN
-3
TYP
MAX
UNITS
+3
NC
11
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
AC ELECTRICAL CHARACTERISTICS
(VCC = +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
TXD Rising Edge to Fault Clear
tOFF
From h TXD (Notes 8, 9)
5
Fs
TXD Falling Edge to TXDOUT
Falling
tON
From i TXD (Note 10)
5
Fs
Recovery After Power-Up:
MAX3710
tINIT_3710
From h VCC > POA (Note 11)
1
ms
Recovery After Power-Up:
MAX3710 and MAX3945
tINIT_3945
From h VCC > VCC LO alarm or warning
(Note 12)
1
ms
30
ms
12.5
ms
Fault Assert Time
(to TXFOUT = 1)
tINITR1
From i TXD
Fault Reset Time at Power-On
(to TXFOUT = 0)
tINITR2
From h VCC > POA, Figure 12c (Note 13)
STARTUP TIMING CHARACTERISTICS
(VCC= +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
Output Enable Time Following
POA
tINIT
CONDITIONS
MIN
(Notes 13, 14)
TYP
MAX
13
UNITS
ms
3-WIRE DIGITAL INTERFACE SPECIFICATION
(VCC = +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted. Timing is referenced to VIL(MAX) and VIH(MIN).) (Note 1)
(See Figure 13.)
PARAMETER
SCLOUT Clock Frequency
SYMBOL
CONDITIONS
MIN
fSCLOUT
TYP
MAX
1.05
UNITS
MHz
SCLOUT Duty Cycle
t3WDC
50
%
SDAOUT Setup Time
tDS
500
ns
SDAOUT Hold Time
tDH
100
ns
CSEL1OUT, CSEL2OUT Pulse-Width
Low
tCSW
1
Fs
CSEL1OUT, CSEL2OUT Leading
Time Before the First SCLOUT Edge
tL
1
Fs
CSEL1OUT, CSEL2OUT Trailing
Time After the Last SCLOUT Edge
tT
1
Fs
SDAOUT, SCLOUT Load
CB3W
Total bus capacitance on one line
10
pF
12
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
I2C AC ELECTRICAL CHARACTERISTICS
(VCC = +2.97V to +3.63V, TA = -40NC to +95NC, unless otherwise noted. Timing is referenced to VIL(MAX) and VIH(MIN).) (Note 1) (See
Figure 19.)
PARAMETER
SYMBOL
CONDITIONS
TYP
UNITS
400
kHz
Clock Pulse-Width Low
tLOW
1.3
Fs
Clock Pulse-Width High
tHIGH
0.6
Fs
Bus Free Time Between STOP and
START Condition
tBUF
1.3
Fs
tHD:STA
0.6
Fs
START Setup Time
tSU:STA
0.6
Data in Hold Time
tHD:DAT
0
Data in Setup Time
tSU:DAT
Rise Time of Both SDA and SCL
Signals
Fall Time of Both SDA and SCL
Signals
STOP Setup Time
0
MAX
fSCL
START Hold Time
(Note 15)
MIN
SCL Clock Frequency
100
tR
(Note 16)
tF
(Note 16)
CB
EEPROM Write Time
tW
Fs
ns
20 +
0.1CB
20 +
0.1CB
tSU:STO
Capacitive Load for Each Bus Line
Fs
0.9
300
ns
300
ns
400
pF
20
ms
MAX
UNITS
0.6
Fs
(Note 17)
NONVOLATILE MEMORY CHARACTERISTICS
(VCC = +2.97V to +3.63V, unless otherwise noted.) (Note 1)
PARAMETER
EEPROM Write Cycles
SYMBOL
CONDITIONS
At TA = +25NC
MIN
TYP
50,000
—
10,000
At TA = +85NC
Note 1: Limits are production tested at TA = +25°C. Limits over the operating temperature range and relevant supply voltage
range are guaranteed by design and characterization. Typical values are not guaranteed.
Note 2: All voltages are referenced to ground. Current entering the IC is considered positive, and current exiting the IC is considered negative.
Note 3: Inputs are at supply rail. Outputs are not loaded. Does not include REFIN current. Measured using the Typical Operating
Circuit—GPON ONU.
Note 4: The ADC output is available internally as a 16-bit value. The 16 bits are derived by left-shifting the 13-bit ADC output by 3.
Note 5: Guaranteed by design.
Note 6: TXB (transmit bias) and TXP (transmit power) are separate ADC conversions that are performed on the same input pin, TXMON.
Note 7: Full scale is user-programmable.
Note 8: Time until faults are cleared (falling edge of TXFOUT).
Note 9: Time until rising edge of TXDOUT.
Note 10:Time until falling edge of TXDOUT.
Note 11:Time until completion of initial MAX3710 control registers configuration.
Note 12:Time until completion of initial MAX3945 and MAX3710 control registers configuration.
Note 13:VCC LO alarm or warning is enabled, a VCC conversion is completed, and VCC is above VCC LO alarm or warning. See
Figure 12c.
Note 14:DAC output valid, 3-wire writes from LUTs complete, and digital outputs valid.
Note 15:I2C interface timing shown is for fast-mode (400kHz) operation. This device is also backward compatible with I2C standard mode.
Note 16:CB = Total capacitance of one bus line in pF.
Note 17:EEPROM write begins after a STOP condition occurs.
13
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
+95°C
0.65
0.60
+25°C
0.55
0.50
-40°C
0.45
0.9
VCC = 3.9V
0.8
SUPPLY CURRENT (mA)
0.40
0.7
0.6
0.5
0.3
0.2
0.35
0.1
SDA = SCL = VCC
0.30
2.85
3.10
3.35
3.60
SDA = SCL = VCC
0
3.85
10
-40
VCC (V)
TXMON AND RSSI DNL
1
0
-1
USING FACTORY-PROGRAMMED
FULL-SCALE VALUE OF 2.5V
-3
0
0.5
1.0
1.5
2.0
VCC = 3.3V
0.8
TXMON AND RSSI DNL (LSB)
2
TXMON AND RSSI INL (LSB)
1.0
DS1886 toc03
VCC = 3.3V
-2
60
TEMPERATURE (°C)
TXMON AND RSSI INL
3
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
USING-FACTORY PROGRAMMED
FULL-SCALE VALUE OF 2.5V
-0.8
-1.0
2.5
0
TXMON AND RSSI INPUT VOLTAGE (V)
0.5
1.0
1.5
2.0
2.5
TXMON AND RSSI INPUT VOLTAGE (V)
DAC INL
DAC DNL
1.5
0.8
0.6
DAC DNL (LSB)
1.0
0.5
0
-0.5
DS1886 toc06
1.0
DS1886 toc05
2.0
DAC INL (LSB)
VCC = 2.85V
VCC = 3.3V
0.4
DS1886 toc04
SUPPLY CURRENT (mA)
0.70
DS1886 toc02
0.75
SUPPLY CURRENT vs. TEMPERATURE
1.0
DS1886 toc01
0.80
0.4
0.2
0
-0.2
-0.4
-1.0
-0.6
-1.5
-0.8
-2.0
-1.0
0
100
200
300
DAC POSITION (DEC)
400
500
0
100
200
300
400
500
DAC POSITION (DEC)
14
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
TXF
LOSOUT
SDAOUT
SCLOUT
CSEL1OUT
Pin Configuration
24
23
22
21
20
TOP VIEW
+
Pin Description
PIN
NAME
FUNCTION
1
CSEL2OUT
2
SCL
I2C Serial-Clock Input
3
SDA
Open-Drain I2C Serial-Data Input/
Output
4
TXFOUT
Open-Drain Transmit Fault Output
5
LOS
Loss-of-Signal Input
Chip-Select Output. Part of the
3-wire interface to the MAX3945.
CSEL2OUT
1
19
REFIN
SCL
2
18
DAC
6
IN1
Digital Maskable Fault Input
SDA
3
17
GND
7
TXD
Transmit Disable Input
TXFOUT
4
16
VCC
8, 15,
17
GND
Ground
LOS
5
15
GND
9
RSEL
Rate Select Input
IN1
6
14
VCC
10
TXDOUT
TXD
7
13
TXMON
11, 12
RSSIP,
RSSIN
Differential External Monitor Input
13
TXMON
External Monitor Input for Both
Transmit Power (TXP) and Transmit
Bias (TXB)
DS1886
8
9
10
11
12
GND
RSEL
TXDOUT
RSSIP
RSSIN
EP
TQFN
(4mm × 5mm × 0.75mm)
Transmit Disable Output
14, 16
VCC
Power-Supply Input
18
DAC
DAC Output
19
REFIN
20
CSEL1OUT
Chip-Select Output. Part of the
3-wire interface to the MAX3710.
21
SCLOUT
Serial-Clock Output. Part of the
3-wire interface to the MAX3710.
22
SDAOUT
Serial-Data Input/Output. Part
of the 3-wire interface to the
MAX3710.
23
LOSOUT
Open-Drain Receive Loss-ofSignal Output
24
TXF
Transmit Fault Input
—
EP
Exposed Pad. Connect to ground.
Reference Input for DAC Full Scale
15
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Block Diagram
REFIN
A2h MEMORY
EEPROM/SRAM
SDA
I2C
INTERFACE
SCL
VCC
EEPROM
256 BYTES
AT A0h
10-BIT
DELTA-SIGMA
DAC
ADC CONFIGURATION/RESULTS,
SYSTEM STATUS/CONTROL BITS,
ALARMS/WARNINGS,
LOOKUP TABLES,
USER MEMORY
SDAOUT
VCC
TXP
RSSIP
CSEL1OUT
13-BIT
ADC
DS1886
POA AND
POD
RESET
RSSIN
SCLOUT
CSEL2OUT
CALCULATED
TXP
TXMON
ANALOG MUX
MON_SEL
3-WIRE
MASTER
TXB
TXFOUT
TEMPERATURE
SENSOR
TXD
VCC
CONFIGURABLE
LOGIC
TXF
TXDOUT
IN1
RSEL
LOSOUT
CONFIGURABLE
LOGIC
LOS
GND
*See Figure 1a, 1b
16
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Typical Operating Circuit—GPON ONU
DS3920
CURRENT MONITOR
DC-DC OUTPUT
APD-TIA
MAX3710
LA
LOS
LOS
DAC
3W
MD AND DFB
MOD
DAC
FAULT
DISABLE
BIAS
DAC
LPD
LASER SIGNAL DETECT
LDD
MDIN
BMON
3W
2.5V REF
DC-DC CONTROL
REFIN
BENP/N
DS1886
EEPROM
IN1
TXF
TXFOUT
TXDOUT
TXD
TX_FAULT
TX_DISABLE
DAC
I2C
TXMON
RSSIP
RSSIN
ADC
SDA
SCL
RSEL
LOS
LOSOUT
MODE_DEF2 (SDA)
MODE_DEF1 (SCL)
RATE SELECT
LOS
17
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Typical Operating Circuit—10G PON ONU
DS3920
CURRENT MONITOR
DC-DC OUTPUT
10G
APD-TIA
MAX3945
10G LA
LOS
3W
MAX3710
3W
MD AND DFB
1.25G TO 2.5G
TOSA
MOD
DAC
FAULT
DISABLE
BIAS
DAC
LPD
LASER SIGNAL DETECT
LDD
MDIN
BMON
3W
2.5V REF
DC-DC CONTROL
REFIN
BENP/N
DS1886
EEPROM
IN1
TXF
TXFOUT
TXDOUT
TXD
TX_FAULT
TX_DISABLE
DAC
I2C
TXMON
RSSIP
RSSIN
ADC
SDA
SCL
RSEL
LOS
LOSOUT
MODE_DEF2 (SDA)
MODE_DEF1 (SCL)
RATE SELECT
LOS
18
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Monitors and Fault Detection
Detailed Description
Monitors
The DS1886 monitors five ADC channels. This monitoring
combined with the alarm enables (A2h Table 01h/05h)
determines when/if the DS1886 turns off the MAX3710
DACs and triggers the TXFOUT and TXDOUT outputs.
All the monitoring levels and interrupt masks are userprogrammable. See Figure 1a.
The DS1886 integrates the control and monitoring functionality required to implement an SFP or PON ONU
system using the Maxim MAX3710 or other compatible
laser driver and limiting amplifier. Key components of the
DS1886 are shown in the Block Diagram and described
in subsequent sections.
Table 1. Acronyms
ACRONYM
ADC
DESCRIPTION
Analog-to-Digital Converter
APC
Automatic Power Control
APD
Avalanche Photodiode
DAC
Digital-to-Analog Converter
LOS
Loss of Signal
LUT
LUT
NV
Nonvolatile
QT
Quick Trip
ROSA
SEE
ACRONYM
SFF
SFF-8472
SFP
SFP+
TIA
TOSA
TXP
Shadowed EEPROM
TXP =
Tracking Error. Deviation from linear of the
relationship between transmitted power and
monitor diode current.
TE
Receiver Optical Subassembly
(A)
DESCRIPTION
Small Form Factor
Document Defining Register Map of SFPs
and SFFs
Small Form-Factor Pluggable
Enhanced SFP
OFFSET
REGISTERS
65,536
(MD0REGH[7:0] + 8
16
x
x MD1REGH[7:0])
TXP SCALE
16
RIGHT-SHIFT1
DETERMINED
BY KIMD
RIGHT-SHIFT2
DETERMINED
BY KRMD
SHIFT
SHIFT
Transimpedance Amplifier
Transmit Optical Subassembly
Transmit Power
16
RESULTS
REGISTERS
16
COMPARE
COUPLED*
*USER HAS TO CALIBRATE THE GAIN USING THE SCALE REGISTERS
IN CASE RIGHT-SHIFTING IS DESIRED IN ORDER TO MAINTAIN CORRECT BIT WEIGHTING.
ALARM/
WARNING
FLAGS
TXFINT
ALARM/
WARNING
ENABLES
ALARM AND WARNING
THRESHOLDS
Figure 1a. ADC Channel Only for TXP when BURST_MODE = 1 in Table 02h, Register 89h
(B)
ANALOG INPUT
OFFSET
REGISTERS
SCALE
REGISTERS
ADC
13
RIGHT-SHIFT
SETTINGS
13
SHIFT
13
RESULTS
REGISTERS
13
COMPARE
COUPLED*
*USER HAS TO CALIBRATE THE GAIN USING THE SCALE REGISTERS
IN CASE RIGHT-SHIFTING IS DESIRED IN ORDER TO MAINTAIN CORRECT BIT WEIGHTING.
ALARM AND WARNING
THRESHOLDS
ALARM/
WARNING
FLAGS
TXFINT
ALARM/
WARNING
ENABLES
Figure 1b. ADC Channel
19
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
ADC Monitors and Alarms
The ADC monitors temperature (internal temp sensor), VCC, laser bias (TXB), laser power (TXP), and
receive power (RSSIC for coarse, RSSIF for fine)
using an analog multiplexer to measure them using
a round-robin scheme with a single ADC (see the
ADC Timing section). The voltage channels have a
customer-programmable full-scale range and all channels have a customer-programmable offset value that
is factory programmed to a default value (Table 2).
Additionally, TXB, TXP, RSSIC, and RSSIF can right-shift
results as described in the Right-Shifting ADC Result
section. This allows customers with specified ADC
ranges to calibrate the ADC input gain by a factor of
2n to measure small signals (thereby reducing the full
scale by a factor of 2n). The DS1886 can then right-shift
the results by n bits (effectively multiplying by a factor
of 1/2n) to maintain the bit weight of their specification.
See the Right-Shifting ADC Result and Enhanced RSSI
Monitoring (Dual Range Functionality) sections for more
information.
Alarms and Warnings
The ADC results (after right-shifting, if used) are
compared to the alarm and warning thresholds after
each conversion, and the corresponding alarms and/
or warnings are set, which can be programmed to
create the internal signal TXFINT. The status of TXFINT
can be read in A2h Lower Memory, Register 71h. TXFINT
is one of the signals used to trigger TXFOUT. TXFOUT
can be programmed to cause TXDOUT outputs. These
ADC thresholds are user-programmable, as are the
masking registers that can be used to prevent the alarms
from triggering the TXFOUT and TXDOUT outputs.
ADC Timing
Five analog channels are digitized in a round-robin
fashion in the order as shown in Figure 2. RSSI is
measured twice to obtain coarse and fine measurements (RSSIC and RSSIF, respectively). The total time
required to convert all channels is tRR (see the Analog
Voltage Monitoring Characteristics table for details). After
each TXMON conversion, a 3-wire communication is
initiated to toggle the MON_SEL bit (bit 6 in the
MAX3710’s TXCTRL2 register, programmed through A2h
Table 02h, Register E5h, bit 6). This causes the laser
driver to alternate sending laser bias (TXB) and laser
power (TXP) signals to the DS1886’s TXMON input.
The DS1886 has a burst mode option to allow internal
calculation of TXP using the MD0 and MD1 register
values read from the MAX3710 over the 3-wire interface. In this option, the sampled TXP value is ignored.
The TXP value in this burst mode is calculated as
follows:
TXP =
(MD0 REGH [7:0] + 8 x
MD1 REGH [7:0])
x 65536
TXP Scale
TXP is then right-shifted (Figure 1a).
RIGHT-SHIFT1 is determined
TXCTRL3[4:3] as follows:
by
KIMD[1:0],
KIMD[1:0]
TXCTRL3[4:3]
NO. OF RIGHT-SHIFTS
00
2
01
1
10
0
11
0
Table 2. ADC Default Monitor Full-Scale Ranges
SIGNAL (UNITS)
+FS SIGNAL
+FS HEX
-FS SIGNAL
-FS HEX
Temperature (°C)
127.996
7FFFh
-128
8000h
VCC (V)
6.5528
FFF8h
0
0000h
TXB, TXP, RSSIC, RSSIF (V)
2.4997
FFF8h
0
0000h
20
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
RIGHT-SHIFT2 is determined
TXCTRL3[2:1] as follows:
by
KRMD[1:0],
KRMD[1:0]
TXCTRL3[4:3]
NO. OF RIGHT-SHIFTS
00
2
01
1
10
0
11
0
must calibrate the corresponding monitors to achieve the
correct LSB weighting. Up to seven right-shift operations
are allowed and are executed as a part of every conversion before the results are compared to the high and low
alarm levels, or loaded into their corresponding measurement registers (Lower Memory, Registers 64h–69h). This
is true during the setup of internal calibration as well as
during subsequent data conversions.
In burst mode, right-shifting for TXP is determined by
KIMD and KRMD.
Right-Shifting ADC Result
The right-shift operation on the ADC result is carried out
based on the contents of right-shift control registers (A2h
Table 02h, Register 8Eh and A2h Table 02h, Register
8Fh) in EEPROM. TXB, TXP, RSSIC, and RSSIF have 3
bits allocated to set the number of right-shifts. The user
Differential RSSI Input
The DS1886 offers a fully differential input for RSSI
that enables high-side monitoring of RSSI, as shown in
Figure 3. This reduces board complexity by eliminating
the need for a high-side differential amplifier or a current mirror.
tRR
TEMP
VCC
TXB
TOGGLE MON_SEL
RSSIC
RSSIF
TXP
TEMP
TOGGLE MON_SEL
NOTE: IF VCC LO ALARM OR WARNING IS ENABLED AT POWER-UP, THE ADC ROUND-ROBIN TIMING CYCLES BETWEEN TEMPERATURE AND VCC ONLY UNTIL VCC IS ABOVE
THE VCC LO ALARM THRESHOLD.
Figure 2. ADC Round-Robin Timing
DS1886
VCC
RSSIP
680Ω
RSSIN
ADC
ROSA
Figure 3. RSSI Differential Input for High-Side RSSI
21
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Laser Bias and Laser Power Through TXMON
The DS1886 measures both laser bias (TXB) and laser
power (TXP) through the same input pin, TXMON. The
DS1886 commands the MAX3710 laser driver to output
the correct monitor signal before each ADC conversions
takes place. Figure 4 shows the two conversion paths.
Each path has independent gain and offset calibration
registers.
Enhanced RSSI Monitoring
(Dual Range Functionality)
The DS1886 offers a feature to improve the accuracy
and range of RSSI, which is most commonly used for
monitoring RSSI. To achieve the SFF-8472 requirement of
0.1µW/LSB over -40 to 8.2dBm, the DS1886 makes two
measurements to effectively achieve a 16-bit conversion
with a 13-bit physical ADC. This “dual range” calibration
can operate in two modes: APD mode and PIN mode.
BMON
APD Mode
For systems with a nonlinear relationship between the ADC
input and desired ADC result, the mode should be set to
APD mode (Figure 5). The RSSI measurement of an APD
receiver is one such application. Using the APD mode
allows a piece-wise linear approximation of the nonlinear
response of the APD’s gain factor. The crossover point is
the point between fine and coarse points. The ADC result
transitions between the fine and coarse ranges with no
hysteresis. Right-shifting, slope adjustment, and offset
are configurable for both the fine and coarse ranges. Two
registers, XOVER FINE and XOVER COARSE, determine
the crossover point. The XOVER FINE register (A2h Table
02h, Register A0h–A1h) determines the maximum results
returned by fine ADC conversions, before right-shifting.
The XOVER COARSE register (A2h Table 02h, Register
90h–91h) determines the minimum results returned by
coarse ADC conversions, before right-shifting.
BMON
MAX3710
MON_SEL = 1
MAX3710
MON_SEL = 0
DS1886
DS1886
TXB
TXB
ADC
TXMON
ADC
TXMON
TXP
TXP
ADC
ADC
Figure 4. Laser Bias (TXB) and Laser Power (TXP) Monitoring Through TXMON
-S
CA
LE
RE
SP
ON
SE
RSSI RESULT
CO
AR
SE
FU
LL
CROSSOVER POINT
ONSE
CALE RESP
FINE FULL-S
IDEAL RESPONSE
RSSI INPUT
APD MODE
Figure 5. RSSI in APD Mode
22
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
gives the best resolution for the measurement. Table 3
shows the threshold values for each possible number of
right-shifts.
PIN Mode
The PIN mode is intended for systems with a linear relationship between the RSSI input and desired ADC result.
The ADC result transitions between the fine and coarse
ranges with hysteresis, as shown in Figure 6.
Low-Voltage Operation
The DS1886 contains two power-on reset (POR) levels.
The lower level is a digital POR (POD) and the higher
level is an analog POR (POA). At startup, before the
supply voltage rises above POA, the outputs are disabled, all SRAM locations are set to their defaults,
shadowed EEPROM locations are zero, and all analog
In PIN mode, the thresholds between coarse and fine
mode are a function of the number of right-shifts being
used. With the use of right-shifting, the fine mode full scale
is programmed to (1/2nth) of the coarse mode full scale.
The DS1886 now auto ranges to choose the range that
PON
SE
RSSI RESULT
RES
ALE
L-SC
FINE
FUL
CO
FT
SHI
TIGH
ER
FIN
C
L-S
UL
EF
S
AR
SE
ON
ESP
R
ALE
=3
HYSTERESIS
RSSI INPUT
FINE
COARSE
PIN MODE
Figure 6. RSSI in PIN Mode
Table 3. RSSI Hysteresis Threshold Values
# OF RIGHTSHIFTS
FINE MODE
MAX (HEX)
COARSE MODE
MIN* (HEX)
0
FFF8h
F000h
1
7FFCh
7800h
2
3FFEh
3C00h
3
1FFFh
1E00h
4
0FFFh
0F00h
5
07FFh
0780h
6
03FFh
03C0h
7
01FFh
01E0h
*This is the minimum reported coarse mode conversion.
Table 4. RSSI Configuration Registers
REGISTER
FINE MODE
COARSE MODE
Gain Register
(RSSI FINE/COARSE
SCALE)
98h–99h, A2h
Table 02h
9Ch–9Dh, A2h
Table 02h
Offset Register
(RSSI FINE/COARSE
OFFEST)
A8h–A9h, A2h
Table 02h
ACh–ADh, A2h
Table 02h
8Eh, A2h
Table 02h
N/A
RIGHT-SHIFT1 Register
RSSIC and RSSIF Bits
(RIGHT-SHIFT0)
8Fh, A2h Table 02h
RSSIR Bit (UPDATE)
6Fh, A2h Lower Memory
RSSI Measurement
(RSSI VALUE)
68h–69h, A2h Lower Memory
23
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
circuitry is disabled. When VCC reaches POA, the SEE is
recalled, and the analog circuitry is enabled. While VCC
remains above POA, the device is in its normal operating
state, and it responds based on its nonvolatile configuration. If during operation VCC falls below POA, but is still
above POD, the SRAM retains the SEE settings from the
first SEE recall, but the device analog is shut down and
the outputs are disabled. If the supply voltage recovers
back above POA, the device immediately resumes normal operation. If the supply voltage falls below POD, the
device SRAM is placed in its default state and another
SEE recall is required to reload the nonvolatile settings.
The EEPROM recall occurs the next time VCC next
exceeds POA. Figure 7 shows the sequence of events
as the voltage varies.
Any time VCC is above POD, the I2C interface can be
used to determine if VCC is below the POA level. This is
accomplished by checking the RDYB bit in the STATUS
byte (A2h Lower Memory, Register 6Eh). RDYB is set
when VCC is below POA; when VCC rises above POA,
RDYB is timed (within 500Fs) to go to 0, at which point
the part is fully functional.
For all device addresses sourced from EEPROM (A2h
Table 02h, Register 8Ch), the default DEVICE ADDRESS
is A2h until VCC exceeds POA, allowing the device
address to be recalled from the EEPROM.
Power-On Analog (POA)
POA holds the DS1886 in reset until VCC is at a suitable
level (VCC > POA) for the device to accurately measure
with its ADC and compare analog signals with its quicktrip monitors. Because VCC cannot be measured by the
ADC when VCC is less than POA, POA also asserts the
VCC LO alarm, which is cleared by a VCC ADC conversion greater than the customer-programmable VCC low
ADC limit. This allows a programmable limit to ensure
that the head room requirements of the transceiver are
satisfied during a slow power-up. The TXFOUT output
does not latch until there is a conversion above the VCC
low limit. The POA alarm is nonmaskable. See the LowVoltage Operation section for more information.
SEE RECALL
SEE RECALL
VPOA
VCC
VPOD
SEE
PRECHARGED
TO 0
RECALLED VALUE
PRECHARGED TO 0
RECALLED VALUE
PRECHARGED
TO 0
Figure 7. Low-Voltage Hysteresis Example
24
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Delta-Sigma Output and Reference
One delta-sigma output (DAC) is provided. This provides
a 10-bit resolution output. The maximum voltage output is
set by the input REFIN. An inexpensive shunt reference is
recommended to generate the voltage applied to REFIN,
as shown in Figure 8. The output includes the ability to
compensate the APD bias for temperature as given by
the following formula:
DAC_INT = TINDEX[6:0] + DAC OFFSET
If INV_DAC = 0, then DAC[9:0] = DAC_INT/DACFS x
VREFIN.
If INV_DAC = 1, then DAC[9:0] = [3FF - (DAC_INT/
DACFS)] x VREFIN.
where:
digital PWM output given the same clock rate and filter
components. An RC filter is required on the DAC output
as suggested in Figure 8. The external RC filter components are chosen based on ripple requirements, output
load, delta sigma frequency, and desired response time.
Before tINIT, the DAC output is high impedance.
The reference input, REFIN, is the supply voltage for the
DAC’s output buffer. The voltage source connected to
REFIN must be able to support the edge rate requirements of the delta sigma outputs. In a typical application,
a 0.1uF capacitor should be connected between REFIN
and ground.
The DS1886’s delta-sigma output is 10 bits. For illustrative purposes, a 3-bit example is provided in Figure 9.
1) INV_DAC is at A2h Table 02h, Register 8Dh, bit 7.
VCC
2) TINDEX is at A2h Table 02h, Register 81h.
3)DAC OFFSET is an 8-bit value, representing the 8
MSBs of a 10-bit value. The two LSBs are 0.
4)DACFS (A2h Table 02h, Register 88h) is an 8-bit
value, representing the 8 MSBs of a 10-bit value. The
two LSBs are 0.
5) DAC is a 10-bit value.
6) The DAC[9:0] is clamped at DACFS.
1kΩ
0201
REFIN
DS1886
2.5V
0.1µF
0201
68.1kΩ
0201
39.2kΩ
0201
ZTL431A
SOT23
DAC
1µF
0402
20kΩ
0201
CONNECT TO
CONTROL INPUT
ON DC-DC
7) DAC_INT is an internal signal.
The delta-sigma output uses pulse-density modulation.
It provides much lower output ripple than a standard
Figure 8. Recommended Shunt Reference and RC Filter for
DAC Output
O
1
2
3
4
5
6
7
Figure 9. Delta-Sigma Output
25
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
VCC
TXDS
RPU
TXD
C
TXDC
TXD
R
C
D
TXDIO
Q
TXDOUT
Q
TXDFLT
TXFOUTS
TXFOUT
TXFINT
INVTXF
TXF
tINITR1
FAULT RESET TIMER
(130ms)
OUT
IN
IN
OUT
PINS
TXFS
POWER-ON
RESET
IN1EN
IN1
IN1S
Figure 10. TXFOUT and TXDOUT Logic Diagram.
RSELS
3-WIRE
SET_LOS_3945
RSEL
= PINS
Figure 11. RSEL Logic Diagram
Digital I/O Pins
Five digital inputs and three digital output pins are provided for monitoring and control.
LOS, LOSOUT
By default, the LOS pin is used to convert a standard
comparator output for loss of signal (LOS) to an opencollector output (LOSOUT). The status of LOS can be read
in the STATUS byte (A2h Lower Memory, Register 6Eh) as
the RXL bit. The RXL signal can be inverted (INV LOS = 1)
before driving the open drain output transistor.
RSEL
The level of RSEL can be read by reading the STATUS
register (A2h Lower Memory, Register 6Eh). The status
of RSEL determines whether SETLOSL or SETLOSH is
written to the MAX3945 register SET_LOS.
TXD, TXDOUT
TXDOUT is generated from a combination of TXFOUT
and TXD (see the CNFGC register A2h Table 02h,
Register 8Bh for enabling these options). A software
control identical to TXD is available (TXDC, A2h Lower
Memory, Register 6Eh). A TXD pulse is internally extended (tINITR1) to inhibit the latching of low alarms and
warnings. The intended use is a direct connection to the
MAX3710’s DISABLE input if this is desired. When VCC <
POA, TXDOUT is high impedance.
IN1, TXF, Transmit Fault (TXFOUT) Output
TXFOUT can be triggered by all alarms and warnings and
also the pins TXF and IN1 (Figure 10). The ADC alarms and
warnings require enabling (A2h Table 01h/05h, Registers
26
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
F8h and FDh). See Figure 12a and Figure 12b for nonlatched and latched operation. Figure 12c describes
this TXFOUT behavior during power-on. Latching of the
alarms is controlled by CNFGB and CNFGC Registers
(A2h Table 02h, Register 8Ah and A2h Table 02h,
Register 8Bh).
The DS1886 monitors the IMODOVFL and IBIASOVFL
bits in the MAX3710 DPCSTAT register. If any of these
bits is set, the user can optionally cause TXFOUT to be
set. A mask bit, BIASMODOVFL_FLT in A2h Table 02h,
Register 8Bh, must be set to enable this functionality.
Die Identification
The DS1886 has an ID hardcoded in its die. Two
registers (DEVICE ID A2h Table 02h, Register CEh and
DEVICE VER A2h Table 02h, Register CFh) are assigned
for this feature. Register CEh reads 84h to identify with
the device as the DS186, and Register CFh reads the
present device version.
DETECTION OF
TXFOUT FAULT
TXFOUT
Figure 12a. TXFOUT Nonlatched Operation
DETECTION OF
TXFOUT FAULT
TXD OR
TXF RESET
TXFOUT
Figure 12b. TXFOUT Latched
VCC
VPOA
tINITR2
TXFOUT1
TXFOUT2
CONDITION 1: VCC LO ALARM OR WARNING FLAG ENABLED TO CREATE TXF. VCC IS ABOVE CORRESPONDING VCC LO ALARM/WARNING THRESHOLD.
CONDITION 2: VCC LO ALARM AND WARNING FLAGS ARE NOT ENABLED.
Figure 12c. TXFOUT During Power-On
27
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
DS1886 Master Communication
Interface
device(s). It is a 3-pin interface consisting of SDAOUT,
a bidirectional data line; clock signal SCLOUT; and
CSEL1OUT chip-select output (active high). A second,
independent chip select (CSEL2OUT) is provided for use
with the MAX3945.
The DS1886 controls the MAX3710 using a proprietary
3-wire interface. The DS1886 configures the MAX3710 on
startup and then continuously updates the MAX3710 with
new LUT values. The DS1886 operates in one of three
modes: open loop, APC loop, and dual closed loop. The
DS1886 can also configure the MAX3945 on startup. The
communication between the DS1886 and the MAX3710
and MAX3945 is transparent to the end user. In addition,
commands can be issued to the MAX3710 and MAX3945
using the DS1886’s manual mode.
Protocol
The DS1886 initiates a data transfer by asserting the
CSEL1OUT or CSEL2OUT pin. It then starts to generate
a clock signal after CSEL1OUT or CSEL2OUT has been
set to 1. Each operation consists of 16 bit transfers (15-bit
address/data, 1-bit RWN). All data transfers are MSB first.
Write Mode (RWN = 0): The master generates 16 clock
cycles at SCLOUT in total. It outputs 16 bits (MSB first)
to the SDAOUT line at the falling edge of the clock. The
master closes the transmission by setting CSEL1OUT
and CSEL2OUT to 0.
3-Wire Master Interface
The DS1886 acts as the master, initiating communication with and generating the clock for the Maxim slave
Read Mode (RWN = 1): The master generates 16 clock
cycles at SCLOUT in total. It outputs 8 bits (MSB first)
to the SDAOUT line at the falling edge of the clock. The
SDAOUT line is released after the RWN bit has been
transmitted. The slave outputs 8 bits of data (MSB first) at
rising edge of the clock. The master samples SDAOUT at
the falling edge of SCLOUT. The master closes the transmission by setting the CSEL1OUT and CSEL2OUT to 0.
Table 5. 3-Wire Transaction Detail
BIT
NAME
15:9
Address
DESCRIPTION
8
RWN
0: write, 1: read
7:0
Data
8-bit read or write data
7-bit internal register address
WRITE MODE
CSEL_OUT
tL
tT
tCH tCL
0
SCLOUT
1
2
3
4
5
6
7
8
9
A4
A3
A2
A1
A0
RWN
D7
D6
10
11
12
13
14
15
tDS
SDAOUT
A6
A5
D5
D4
D3
D2
D1
D0
tDH
READ MODE
CSEL_OUT
tL
tT
tCH tCL
SCLOUT
0
1
2
3
4
5
6
7
A4
A3
A2
A1
A0
RWN
8
9
10
tRS
tDS
SDAOUT
A6
A5
D7
D6
11
D5
12
D4
13
D3
14
D2
15
D1
D0
tDH
NOTE: SEE THE 3-WIRE DIGITAL INTERFACE SPECIFICATION TABLE FOR DETAILS. CSEL_OUT IMPLIES CSEL1OUT OR CSEL2OUT.
Figure 13. 3-Wire Interface Timing Diagram
28
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
3-Wire Slave Register Map and DS1886
Corresponding Location
When the MAX3945 registers are written, the MAX3710
are also written simultaneously (Table 6).
3-Wire Master Flowchart
Figure 14 explains the working of the 3-wire master in
the DS1886 in all three opreating modes. These modes
are described in the DS1886 with MAX3710 Operating
Modes section.
Table 6. 3-Wire Register Map and DS1886 Corresponding Location
DS1886 REGISTER
(A2h TABLE 02h)
DS1886
REGISTER NAME
MAX3710
ADDRESS
MAX3710
REGISTER NAME
MAX3945
ADDRESS
MAX3945
REGISTER NAME
82h–83h
MODULATION VALUE
0Eh
SET_IMOD
N/A
N/A
85h
APC VALUE
11h
SET_2XAPC
N/A
N/A
86h–87h
SET_BIAS VALUE
0Dh
SET_IBIAS
N/A
N/A
CAh
INCBYTE[7:4]
0Fh
BIASINC
N/A
N/A
CAh
INCBYTE[3:0]
10h
MODINC
N/A
N/A
CBh
TXCTRL5 DPC
0Ah
TXCTRL5
N/A
N/A
CCh
IMODMAX
0Ch
IMODMAX
N/A
N/A
CDh
IBIASMAX
0Bh
IBIASMAX
N/A
N/A
E0h
RXCTRL1
01h
RXCTRL1
00h
RXCTRL1
E1h
RXCTRL2
02h
RXCTRL2
01h
RXCTRL2
E2h
SETCML
03h
SET_CML
03h
SET_CML
E3h
SETLOSH
04h
SET_LOS
N/A
N/A
E4h
TXCTRL1
06h
TXCTRL1
N/A
N/A
E5h
TXCTRL2
07h
TXCTRL2
N/A
N/A
E6h
TXCTRL3
08h
TXCTRL3
N/A
N/A
E7h
TXCTRL4
09h
TXCTRL4
N/A
N/A
E8h
TXCTRL5 APC OL
0Ah
TXCTRL5
N/A
N/A
E9h
TXCTRL6
13h
TXCTRL6
N/A
N/A
EAh
TXCTRL7
05h
TXCFG
N/A
N/A
ECh
SETLOSH_3945
N/A
N/A
04h
SET_LOS
EDh
SETLOSL_3945
N/A
N/A
04h
SET_LOS
EEh
SETLOSTIMER_3945
N/A
N/A
12h
SET_LOSTIMER
F0h
3WCTRL
F1h
ADDRESS
F2h
WRITE
F3h
READ
F4h
TXSTAT2
1Fh
TXSTAT2
N/A
N/A
F5h
TXSTAT1
1Eh
TXSTA1
N/A
N/A
F6h
DPCSTAT
1Dh
DPCSTAT
N/A
N/A
F7h
RXSTAT
1Ch
RXSTAT
N/A
N/A
Manual control of read/write from/to 3-wire slave devices; useful for determining
correct settings for the slave devices and also for debugging.
29
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
READ REGISTERS
BIAS REG, MOD REG,
RXSTAT, DPCSTAT,
TXSTAT1, TXSTAT2,
MD0REGH,
MD1REGH,
SET_2XAPC
BURST_MODE = 1
AND
MD1REGH <17?
Y
TXD_STANDBY
TOGGLE MONSEL
N
A
TXD = 1
OR
POR = 1
Y
N
RESET
(SET TXD_FLAG IF TXD = 1 AND
SET POR_FLAG IF POR = 1)
N
IDLE
WAIT FOR TEMP_CONV
TXD = 0?
EN_3945 = 1?
N
N
Y
TEMP_CONV = 1?
Y
Y
Y
N
VCC > VCC LO?
WRITE_LUT REGISTERS
TXCTRL5
IMODMAX
IBIASMAX
SET_IMOD
SET_IBIAS
BIASINC
MODINC
SET_2XAPC
Y
WRITE CNTRL
MAX3945
POR_FLAG = 1?
N
MANMODE = 1?
APC_EN = 1?
Y
MANMODE
ALLOWS THE USER TO
COMMUNICATE WITH
MAX3710 USING THE I2C
INTERFACE ON DS1886
DPC_EN = 1?
N
Y
WRITE
MODINC, SET_IMOD
BIASINC, SET_IBIAS
TXD_FLAG = 1?
WRITE
MODINC, SET_IMOD
RSTRT_3710 = 1
OR TXF_LATCHED = 1
INC APC
STEADY STATE (FIG 15)
TOGGLE MONSEL BIT
(TXCTRL2[6])
PERIODICALLY;
RESET FLAGS
WRITE TXCTRL6
Y
TXSTAT1 = FFh?
TXD_FLAG = 1?
N
RSTRT_3710
N
MANMODE = 1?
Y
DPC_EN = 1?
TXINLOS
POR_FLAG* = 1?
N
Y
N
READ
TXSTAT1
Y
WRITE ALL CONTROL
REGISTERS IF ENABLED
WRITE REGISTERS
IBIASMAX
IMODMAX
TXCTRL5
Y
TEMP_CONV = 1
AND DIS3W = 0
N
Y
WRITE CONTROL
RXCTRL1, RXCTRL2,
SET_CML, SET_LOS,
TXCTRL1, TXCTRL2,
TXCTRL3, TXCTRL4
A
N
Y
TEMP_CONV = 1?
AND DIS3W = 0
Y
APC_EN = 1?
N
INC MOD
INC BIAS, MOD
*POR_FLAG IS SET BY A POR. THIS FLAG IS RESET IN THE STEADY STATE.
Figure 14. 3-Wire Flowchart
30
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
STEADY
STATE
NO
TXF = 1?
YES
READ TXSTAT1
YES
TXSTAT1 = FFh?
NO
WRITE_CONTROL
RXCTRL1, RXCTRL2,
SET_CML, SET_LOS,
TXCTRL1, TXCTRL2,
TXCTRL3, TXCTRL4
TXF = 1?
NO
YES
FAULT WAIT
STATE1, 2
TEMP
CONVERSION
COMPLETE?
WRITE TXCTRL6
YES
NO
YES
TXF = 1?
WRITE_LUT REGISTERS
TXCTRL5,
IMODMAX, IBIASMAX,
SET_IMOD, SET_IBIAS,
MODINC, BIASINC,
SET_2XAPC
NO
WRITE_LUT REGISTERS
TXCTRL5,
IMODMAX, IBIASMAX,
SET_IMOD, SET_IBIAS,
MODINC, BIASINC,
SET_2XAPC
WRITE TXCTRL6
NOTE 1: FAULT WAIT STATE HAS ACCESS TO MAX3710 IN MANUAL MODE.
NOTE 2: MON_SEL BIT IS TOGGLED AS NEEDED TO KEEP THE TXP/TXB MONITORS CORRECT.
Figure 15. MAX3710 Brownout Detection Flowchart
3-Wire Power-On Reset
The DS1886 detects whether a power-on reset has
occured on the slave 3-wire device. This is done using
the flowchart shown in Figure 15.
31
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
DS1886 with MAX3710 Operating Modes
The user has the option of selecting among open loop,
APC loop, and dual closed-loop operation modes. These
can be programmed using the DPC_EN and APC_EN
bits in the MAX3710 TXCTRL3 register (Address H0x08),
programmed through A2h Table 02h, Register E6h.
Table 7 indicates what the values in each LUT corresponds to in each of the modes. LUT values are not
automatically updated when changing between operating modes.
Open Loop Mode, DPC_EN = 0, APC_EN = 0
In open loop mode, the laser bias and modulation are
both controlled using LUTs. Each LUT consists of an
8-bit LUT with up to 2NC temperature resolution and an
8-bit offset LUT. This allows the DS1886 to fully support
the 10-bit bias DAC and 9-bit modulation DAC inside the
MAX3710.
APC Loop Mode, DPC_EN = 0, APC_EN = 1
In APC loop or single closed-loop mode, the laser bias
is controlled by an APC loop, while the modulation is
controlled using a temperature-indexed LUT. The APC
setpoint is controlled using an LUT having up to 16NC
resolution. The APC loop initial value (SET_IBIAS) is set
using an LUT having up to 2NC resolution. The modulation LUT consists of an 8-bit LUT with up to 2NC temperature resolution and an 8-bit offset LUT. This allows the
DS1886 to fully support the 10-bit bias DAC and 9-bit
modulation DAC inside the MAX3710.
Dual Closed-Loop Mode, DPC_EN = 1, APC_EN = 1
In dual closed-loop mode, the laser bias is controlled
by an APC loop, while the modulation is controlled with
an extinction ratio loop. The APC setpoint and extinction
ratio setpoints are controlled using 8-bit LUTs with up to
2NC temperature resolution and 8-bit offset LUTs. Each
loop is initialized using 8-byte LUTs.
Table 7. DS1886 LUT Functions in Open Loop, APC Loop, and Dual Closed-Loop Modes
TABLE
04h
06h
08h
REGISTER
OPEN LOOP
APC LOOP
DUAL CLOSED LOOP
80h–A7h
8-Bit Modulation Value [7:0]
8-Bit Modulation Value [7:0]
8-Bit TXCTRL5[7:0]
F0h–F7h
IMODMAX[8:1]
IMODMAX[8:1]
IMODMAX[8:1]
F8h–FFh
Modulation Offset [9:2]
Modulation Offset [9:2]
SET_IMOD[8:1]
(MOD Initial Value)
80h–A7h
8-Bit BIAS Value [7:0]
8-Bit SET_IBIAS [9:2]
8-Bit SET_IBIAS [9:2]
F0h–F7h
IBIASMAX[9:2]
IBIASMAX[9:2]
IBIASMAX[9:2]
F8h–FFh
BIAS Offset [9:2]
8-Bit APC Value [7:0]
8-Bit APC Value [7:0]
F8h–FFh
INCBYTE (set to all zeros)
INCBYTE
7:4 = BIASINC
3:0 = MODINC (set to all zeros)
INCBYTE
7:4 = BIASINC
3:0 = MODINC
32
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
BIAS, MODULATION,
SET_2XAPC, TXCTRL5 LUTs
The LUTs have nonlinear temperature indexing. After
every temperature conversion, based on the internal temperature read, a TINDEX value is calculated, which then
indexes the LUT. The LUTs can index with a resolution
as low as 2NC.
LUTs allow temperature indexing the BIAS and
MODULATION values and their respective offsets.
Depending on the operation mode (see the DS1886 with
MAX3710 Operating Modes section), the LUTs function
differently, as indicated in Table 7.
This is illustrated in Table 8 and Table 9. BIAS, MODULATION
and TXCTRL5 are 5-row LUTs. Further details can be
found in the LUT descriptions.
Table 8. DS1886 LUT Memory Map for 5-Row Table (Temperature Values Indicated in °C)
ROW
BYTE 0
BYTE 1
BYTE 2
BYTE 3
BYTE 4
BYTE 5
BYTE 6
BYTE 7
80h
-40
-32
-24
-16
-8
0
+8
+16
88h
+24
+28
+32
+36
+40
+44
+48
+52
90h
+56
+58
+60
+62
+64
+66
+68
+70
98h
+72
+74
+76
+78
+80
+82
+84
+86
A0h
+88
+90
+92
+94
+96
+98
+100
+102
Table 9. DS1886 LUT Memory Map for 5-Row Table (TINDEX Values Indicated in Hex)
ROW
BYTE 0
BYTE 1
BYTE 2
BYTE 3
BYTE 4
BYTE 5
BYTE 6
BYTE 7
80h
80
84
88
8C
90
94
98
9C
88h
A0
A2
A4
A6
A8
AA
AC
AE
90h
B0
B1
B2
B3
B4
B5
B6
B7
98h
B8
B9
BA
BB
BC
BD
BE
BF
A0h
C0
C1
C2
C3
C4
C5
C6
C7
33
EACH OFFSET REGISTER CAN BE INDEPENDENTLY
SET BETWEEN 0 AND 1020. 1020 = 4 x FFh. THIS
EXAMPLE ILLUSTRATES POSITIVE TEMPCO.
1023
FDh
767
FCh
LUT
BITS
7:0
FBh
511
F8h
0
-40°C
-8°C
LUT
BITS
7:0
LUT
BITS
7:0
LUT
BITS
7:0
LUT
BITS
7:0
255
FAh
F9h
+8°C
LUT
BITS
7:0
FFh
FEh
LUT
BITS
7:0
VALUE DETERMINED BY LUTs WITH CORRESPONDING
OFFSET LUTs
VALUE DETERMINED BY LUTs WITH CORRESPONDING
OFFSET LUTs
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
LUT
BITS
7:0
EACH OFFSET REGISTER CAN BE INDEPENDENTLY SET BETWEEN
0 AND 1020. 1020 = 4 x FFh. THIS EXAMPLE ILLUSTRATES POSITIVE
AND NEGATVE TEMPCO.
1023
767
FCh
FBh
FAh
F9h
511
LUT
BITS
7:0
F8h
LUT
BITS
7:0
255
0
+24°C +40°C +56°C +72°C +88°C +104°C
-40°C
LUT
BITS
7:0
-8°C
+8°C
OFFSET LUTs [8 REGISTERS]
LUT
BITS
7:0
LUT
BITS
7:0
FDh
LUT
BITS
7:0
FEh
LUT
BITS
7:0
FFh
LUT
BITS
7:0
+24°C +40°C +56°C +72°C +88°C +104°C
OFFSET LUTs [8 REGISTERS]
Figure 16. Offset LUT
DS1886
MODULATION VALUE
MOD OFFSET[9:2]
9
8
7
6
5
4
3
2
THE BIAS VALUE THAT IS RECALLED FROM THE LUT AND SENT TO THE MAX3710
IS CALCULATED AS FOLLOWS:
MAX3710
SET_IMOD[8:0]
BIAS OFFSET[9:2]
MOD[7:0]
7
6
5
4
3
2
1
9
0
0
1X
1X
1*
01
-3
01
01
0.5
1X
-6
00
00
0.25
7
6
5
4
3
2
MAX3710
SET_IBIAS[9:0]
POW_LEV POWER KRMD[2:1]
TXCTRL3 GAIN
[1:0]
LEVEL (dB) (MAX3710)
00
8
BIAS[7:0]
7
Figure 17. MODULATION LUT (Open Loop and APC Mode)
6
5
4
3
2
1
0
Figure 18. BIAS LUT (Open Loop)
Table 10. Temperature Resolution for Offsets
ROW
BYTE 0
BYTE 1
BYTE 2
BYTE 3
BYTE 4
BYTE 5
BYTE 6
BYTE 7
F8h
-40NC
-8NC
+8NC
+24NC
+40NC
+56NC
+72NC
+88NC
The offsets are also temperature indexed. Figure 16 illustrates how the offsets would affect the final output as the
temperature varies.
MODULATION Value
Figure 17 shows how to calculate the MODULATION value
that is recalled from the LUT and sent to the MAX3710.
Table 10 shows the temperature resolution for the offsets.
BIAS Value
Figure 18 shows how to calculate the BIAS value that is
recalled from the LUT and sent to the MAX3710.
34
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Table 11a. Power Leveling Details (when DS1863_MODE = 0, default)
POWER LEVEL
(dB)
POW_LEV[1:0]
(REGISTER 6Fh)
MODULATION CHANGE
KRMD[2:1]
(MAX3710)
TXCTRL3
POW_LEV_INIT
0
00
None
1X
1X
-3
01
Right-shift SET_IMOD once
01
01
-6
1X
Right-shift SET_IMOD twice
00
00
Table 11b. Power Leveling Details (when DS1863_MODE = 1)
POWER LEVEL
(dB)
POW_LEV_DS1863[2:0]
(REGISTER 8Ch)
MODULATION CHANGE
KRMD[2:1]
(MAX3710)
0
000–010
None
1X
-3
011–110
Right-shift SET_IMOD once
01
-6
111
Right-shift SET_IMOD twice
00
Power Leveling
The DS1886 supports power leveling as described in
G.984.2. The POW_LEV[1:0] bits in UPDATE A2h Lower
Memory, Register 6Fh allow for three power level settings: 0dB, -3dB, and -6dB. Depending on the operation
mode, a combination of SET_IMOD and the KRMD bits
(MAX3710 TXCTRL3 register) are adjusted to meet these
power-level settings. The KRMD bits adjust the gain of
the APC loop and extinction ratio loop. See Table 11a
and Table 11b.
Manual MAX3710 Operations
The master interface is controllable using four registers
in the DS1886: 3WCTRL, ADDRESS, WRITE, READ.
Commands can be manually issued while the DS1886 is
in normal operation mode. It is also possible to suspend
normal 3-wire commands so that only manual operation
commands are sent (3WCTRL, A2h Table 04h, Register
F8h–FFh).
I2C Communication
I2C Definition
The following terminology is commonly used to describe
I2C data transfers.
Master Device: The master device controls the slave
devices on the bus. The master device generates SCL
clock pulses and START and STOP conditions.
Slave Devices: Slave devices send and receive data
at the master’s request.
Bus Idle or Not Busy: Time between STOP and
START conditions when both SDA and SCL are inactive and in their logic-high states.
START Condition: A START condition is generated by
the master to initiate a new data transfer with a slave.
Transitioning SDA from high to low while SCL remains
high generates a START condition. See Figure 19 for
applicable timing.
STOP Condition: A STOP condition is generated
by the master to end a data transfer with a slave.
Transitioning SDA from low to high while SCL remains
high generates a STOP condition. See Figure 19 for
applicable timing.
Repeated START Condition: The master can use a
repeated START condition at the end of one data transfer
to indicate that it will immediately initiate a new data transfer following the current one. Repeated STARTs are commonly used during read operations to identify a specific
memory address to begin a data transfer. A repeated
START condition is issued identically to a normal START
condition. See Figure 19 for applicable timing.
Bit Write: Transitions of SDA must occur during the
low state of SCL. The data on SDA must remain valid
and unchanged during the entire high pulse of SCL
plus the setup and hold time requirements (Figure 19).
Data is shifted into the device during the rising edge
of the SCL.
Bit Read: At the end a write operation, the master
must release the SDA bus line for the proper amount
of setup time before the next rising edge of SCL during
35
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
a bit read (Figure 19). The device shifts out each bit of
data on SDA at the falling edge of the previous SCL
pulse and the data bit is valid at the rising edge of the
current SCL pulse. Remember that the master generates all SCL clock pulses, including when it is reading
bits from the slave.
slave to the master are read by the master using the bit
read definition, and the master transmits an ACK using
the bit write definition to receive additional data bytes.
The master must NACK the last byte read to terminate
communication so the slave returns control of SDA to
the master.
Acknowledgement (ACK and NACK): An acknowledgement (ACK) or not-acknowledge (NACK) is
always the 9th bit transmitted during a byte transfer. The device receiving data (the master during a
read or the slave during a write operation) performs
an ACK by transmitting a zero during the 9th bit.
A device performs a NACK by transmitting a one
during the 9th bit. Timing for the ACK and NACK is
identical to all other bit writes (Figure 19). An ACK
is the acknowledgment that the device is properly
receiving data. A NACK is used to terminate a read
sequence or as an indication that the device is not
receiving data.
Slave Address Byte: Each slave on the I2C bus
responds to a slave address byte sent immediately
following a START condition. The slave address byte
contains the slave address in the most significant 7 bits
and the R/W bit in the least significant bit.
Byte Write: A byte write consists of 8 bits of information transferred from the master to the slave (most
significant bit first) plus a 1-bit acknowledgement from
the slave to the master. The 8 bits transmitted by the
master are done according to the bit write definition
and the acknowledgement is read using the bit read
definition.
Byte Read: A byte read is an 8-bit information transfer
from the slave to the master plus a 1-bit ACK or NACK
from the master to the slave. The 8 bits of information
that are transferred (most significant bit first) from the
The DS1886 responds to two slave addresses. The
auxiliary memory always responds to a fixed I2C
slave address, A0h. The Lower Memory and Tables
00h–08h respond to I2C slave addresses that can be
configured to any value between 00h–FEh using the
DEVICE ADDRESS byte (A2h Table 02h, Register 8Ch).
The user also must set the ASEL bit (A2h Table 02h,
Register 89h) for this address to be active. By writing
the correct slave address with R/W = 0, the master indicates that it would write data to the slave. If R/W = 1, the
master reads data from the slave. If an incorrect slave
address is written, the device assumes the master is
communicating with another I2C device and ignores
the communications until the next START condition is
sent. If the main device’s slave address is programmed
to be A0h, access to the auxiliary memory is disabled.
Memory Address: During an I2C write operation to the
device, the master must transmit a memory address to
identify the memory location where the slave is to store
SDA
tBUF
tF
tLOW
tHD:STA
tSP
SCL
tHD:STA
tHIGH
tR
tHD:DAT
STOP
START
tSU:STA
tSU:STO
tSU:DAT
REPEATED
START
NOTE: TIMING IS REFERENCED TO VIL(MAX) AND VIH(MIN).
Figure 19. I2C Timing Diagram
36
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
the data. The memory address is always the second
byte transmitted during a write operation following the
slave address byte.
transmitting a memory address before each data byte
is sent. The address counter limits the write to one
8-byte page (one row of the memory map). Attempts to
write to additional pages of memory without sending a
STOP condition between pages results in the address
counter wrapping around to the beginning of the present row.
I2C Protocol
2
See Figure 20 for an example of I C timing.
Writing a Single Byte to a Slave: The master must
generate a START condition, write the slave address
byte (R/W = 0), write the memory address, write
the byte of data, and generate a STOP condition.
Remember that the master must read the slave’s
acknowledgement during all byte write operations.
For example: A 3-byte write starts at address 06h and
writes three data bytes (11h, 22h, and 33h) to three
“consecutive” addresses. The result is that addresses
06h and 07h would contain 11h and 22h, respectively, and the third data byte, 33h, would be written to
address 00h.
Writing Multiple Bytes to a Slave: To write multiple
bytes to a slave, the master generates a START condition, writes the slave address byte (R/W = 0), writes the
memory address, writes up to 8 data bytes, and generates a STOP condition. The device writes 1 to 8 bytes
(one page or row) with a single write transaction. This is
internally controlled by an address counter that allows
data to be written to consecutive addresses without
To prevent address wrapping from occurring, the master must send a STOP condition at the end of the page,
then wait for the bus free time or EEPROM write time
to elapse. Then the master can generate a new START
condition and write the slave address byte (R/W = 0)
and the first memory address of the next memory row
before continuing to write data.
TYPICAL I2C WRITE TRANSACTION
MSB
START
1
MSB
LSB
0
1
0
0
0
SLAVE
ADDRESS*
1
R/W
SLAVE
ACK
b7
LSB
b6
READ/
WRITE
b5
b4
b3
b2
b1
b0
MSB
SLAVE
ACK
b7
LSB
b6
b5
b4
REGISTER ADDRESS
b3
b2
b1
b0
SLAVE
ACK
STOP
DATA
*IF ASEL IS 0, THE SLAVE ADDRESS IS A0h FOR THE AUXILIARY MEMORY AND A2h FOR THE MAIN MEMORY.
IF ASEL = 1, THE SLAVE ADDRESS IS DETERMINED BY TABLE 02h, REGISTER 89h FOR THE MAIN MEMORY. THE AUXILIARY MEMORY CONTINUES TO BE ADDRESSED AT A0h, EXCEPT WHEN THE PROGRAMMED
ADDRESS FOR THE MAIN MEMORY IS A0h.
EXAMPLE I2C TRANSACTIONS WITH A2h AS THE MAIN MEMORY DEVICE ADDRESS
A) SINGLE-BYTE WRITE
-WRITE 00h TO REGISTER BAh
A2h
BAh
00h
SLAVE 0 0 0 0 0 0 0 0 SLAVE
START 1 0 1 0 0 0 1 0 SLAVE
1
0
1
1
1
0
1
0
ACK
ACK
ACK
B) SINGLE-BYTE READ
-READ REGISTER BAh
A2h
BAh
START 1 0 1 0 0 0 1 0 SLAVE
1
0
1
1 1 0 1 0 SLAVE
ACK
ACK
C) TWO-BYTE WRITE
-WRITE 01h AND 75h
TO C8h AND C9h
D) TWO-BYTE READ
-READ C8h AND C9h
REPEATED
START
STOP
A3h
1 0 1 0 0 0 1 1 SLAVE
ACK
DATA
DATA IN BAh
A2h
C8h
01h
75h
SLAVE 0 0 0 0 0 0 0 1 SLAVE 0 1 1 1 0 1 0 1 SLAVE
START 1 0 1 0 0 0 1 0 SLAVE
1
1
0
0
1
0
0
0
ACK
ACK
ACK
ACK
A2h
C8h
START 1 0 1 0 0 0 1 0 SLAVE
1
1
0
0 1 0 0 0 SLAVE
ACK
ACK
REPEATED
START
A3h
1 0 1 0 0 0 1 1 SLAVE
ACK
MASTER
NACK
STOP
MASTER
ACK
DATA IN C9h
STOP
DATA
DATA IN C8h
DATA
MASTER
NACK
STOP
Figure 20. Example I2C Timing
37
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Acknowledge Polling: Any time a EEPROM page is
written, the device requires the EEPROM write time
(tW) after the STOP condition to write the contents of
the page to EEPROM. During the EEPROM write time,
the device does not acknowledge its slave address
because it is busy. It is possible to take advantage
of that phenomenon by repeatedly addressing the
device, which allows the next page to be written as
soon as the device is ready to receive the data. The
alternative to acknowledge polling is to wait for maximum period of tW to elapse before attempting to write
again to the device.
EEPROM Write Cycles: When EEPROM writes occur,
the device writes the whole EEPROM memory page,
even if only a single byte on the page was modified.
Writes that do not modify all 8 bytes on the page are
allowed and do not corrupt the remaining bytes of
memory on the same page. Because the whole page
is written, bytes on the page that were not modified
during the transaction are still subject to a write cycle.
This can result in a whole page being worn out over
time by writing a single byte repeatedly. Writing a page
1 byte at a time wears the EEPROM out 8x faster than
writing the entire page at once. The device’s EEPROM
write cycles are specified in the Nonvolatile Memory
Characteristics table. The specification shown is at the
worst-case temperature. It can handle approximately
10x that many writes at room temperature. Writing to
SRAM-shadowed EEPROM memory with SEEB = 1
does not count as a EEPROM write cycle when evaluating the EEPROM’s estimated lifetime.
Reading a Single Byte from a Slave: Unlike the write
operation that uses the memory address byte to define
where the data is to be written, the read operation
occurs at the present value of the memory address
counter. To read a single byte from the slave, the
master generates a START condition, writes the slave
address byte with R/W = 1, reads the data byte with a
NACK to indicate the end of the transfer, and generates a STOP condition.
Manipulating the Address Counter for Reads: A
dummy write cycle can be used to force the address
pointer to a particular value. To do this, the master
generates a START condition, writes the slave address
byte (R/W = 0), writes the memory address where it
desires to read, generates a repeated START condition, writes the slave address byte (R/W = 1), reads
data with ACK or NACK as applicable, and generates
a STOP condition.
Memory Organization
The following sections provide the device’s register
definitions (see Figure 21 for the memory map). Each
register or row of registers has an access descriptor that
determines the password level required to read or write
the memory. Level 2 password is intended for the module manufacture access only; level 1 password allows
another level of protection for items the end consumer
may wish to protect. Many registers are always readable,
but require password access to write. There are a few
registers that cannot be read without password access.
The below access codes describe each mode used by
the DS1886 with factory setting for the PW_ENA (A2h
Table 02h, Register C0h ) and PW_ENB (A2h Table 02h,
Register C1h) values set to factory settings.
ACCESS
CODE
<0>
READ ACCESS
WRITE ACCESS
At least 1 byte/bit in the row/byte is different
than the rest of the row/byte, so look at each
byte/bit separately for permissions.
<1>
Read all
Write PW2
<2>
Read all
Write not applicable
<3>
Read all
Write all, but the
device hardware
also writes to these
bytes/bits
<4>
Read PW2
Write PW2 +
mode_bit
<5>
Read all
Write all
<6>
Read not applicable
Write all
<7>
Read PW1
Write PW1
<8>
Read PW2
Write PW2
<9>
Read not applicable
Write PW2
<10>
Read PW2
Write not applicable
<11>
Read all
Write PW1
38
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
I2C ADDRESS A0h
I2C ADDRESS A2h
00h
00h
LOWER
MEMORY
NOTE: ALARM ENABLE ROW CAN BE CONFIGURED TO EXIST AT TABLE 01h OR TABLE 05h USING MASK BIT
IN REGISTERS 89h, TABLE 02h.
MAIN DEVICE
EEPROM
(256 BYTES)
AUXILIARY DEVICE
PASSWORD ENTRY
(PWE) (4 BYTES)
TABLE SELECT
BYTE 7Fh
80h
80h
80h
TABLE 02h
NONLOOKUP
TABLE CONTROL
AND
CONFIGURATION
REGISTERS
TABLE 01h
EEPROM
(120 BYTES)
FFh
ALARMENABLE ROW
(8 BYTES)
FFh
TABLE 04h
MODULATION/
TXCTRL5 LUT
EEPROM
TABLE 06h
BIAS/SET_IBIAS LUT
EEPROM
A7h
80h
80h
TABLE 09h
TABLE 08h
A7h
E7h
F7h
F8h
80h
E0h
3W CONFIG
FFh
F0h
MOD MAX LUT
MOD OFFSET/
SET_IMOD LUT
FFh
F8h
TABLE 05h
FFh
F0h
BIAS MAX LUT
BIAS OFFSET/
APC LUT
FFh
F8h
F8h
BIASINC LUT
MODINC LUT
FFh
DAC OFFSET LUT
FFh
Figure 21. Memory Organization
39
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Register Descriptions
The register maps show each byte/word (2 bytes) in terms of its row in the memory. The first byte in the row is located in
memory at the row address (hexadecimal) in the leftmost column. Each subsequent byte on the row is one/two memory
locations beyond the previous byte/word’s address. A total of 8 bytes are present on each row. For more information
about each of these bytes, see the corresponding register description.
A2h Lower Memory Register Map
LOWER MEMORY
WORD 0
WORD 1
WORD 2
WORD 3
ROW
(HEX)
ROW NAME
00
<1>THRESHOLD
0
08
<1>THRESHOLD
1
VCC ALARM HI
VCC ALARM LO
VCC WARN HI
VCC WARN LO
10
<1>THRESHOLD
2
TXB ALARM HI
TXB ALARM LO
TXB WARN HI
TXB WARN LO
18
<1>THRESHOLD
3
TXP ALARM HI
TXP ALARM LO
TXP WARN HI
TXP WARN LO
20
<1>THRESHOLD
4
RSSI ALARM HI
RSSI ALARM LO
RSSI WARN HI
RSSI WARN LO
BYTE 0/8
BYTE 1/9
BYTE 2/A
TEMP ALARM HI
BYTE 3/B
BYTE 4/C
TEMP ALARM LO
BYTE 5/D
BYTE 6/E
TEMP WARN HI
BYTE 7/F
TEMP WARN LO
28–37
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
38–5F
<1>EEPROM
EE
EE
EE
EE
EE
EE
EE
EE
60
<2>ADC
VALUES0
68
<0>ADC
VALUES1
70
78
<5>ALARM/WARN
<0>
TABLE SELECT
TEMP VALUE
<2>RSSI
VALUE
VCC VALUE
TXB VALUE
<2>RESERVED
<2>RESERVED
ALARM3
ALARM2
RESERVED
<5>RESERVED
<5>RESERVED
<5>RESERVED
RESERVED
<6>PWE
WARN3
<6>PWE
MSW
TXP VALUE
<0>STATUS
WARN2
MSW
<6>PWE
LSW
RESERVED
<6>PWE
LSW
<3>UPDATE
RESERVED
<5>TBL
SEL
A2h Table 01h Register Map
A2h TABLE 01h
ROW
(HEX)
ROW NAME
80–BF
C0–F7
F8
WORD 0
WORD 1
WORD 2
WORD 3
BYTE 0/8
BYTE 1/9
BYTE 2/A
BYTE 3/B
BYTE 4/C
BYTE 5/D
BYTE 6/E
BYTE 7/F
<7>EEPROM
EE
EE
EE
EE
EE
EE
EE
EE
<8>EEPROM
EE
EE
EE
EE
EE
EE
EE
EE
ALARM EN3
ALARM EN2
RESERVED
RESERVED
WARN EN3
WARN EN2
RESERVED
RESERVED
<8>ALARM
ENABLE
Note: The ALARM ENABLE bytes (Registers F8h–FFh) can be configured to exist in A2h Table 05h instead of here at A2h Table
01h with the MASK bit (A2h Table 02h, Register 89h). If the row is configured to exist in A2h Table 05, then these locations are EE
in A2h Table 01h.
The access codes represent the factory default values of PW_ENA (A2h Table 02h, Register C0h) and PW_ENB (A2h Table 02h,
Register C1h).
ACCESS
CODE
Read
Access
Write
Access
<0>
See each
bit/byte
separately
<1>
<2>
<3>
<4>
<5>
<6>
<7>
<8>
<9>
<10>
<11>
All
All
All
PW2
All
N/A
PW1
PW2
N/A
PW2
All
PW2
N/A
All and
device
hardware
PW2 +
mode
bit
All
All
PW1
PW2
PW2
N/A
PW1
40
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h Register Map
A2h TABLE 02h (PW2)
ROW
(HEX)
ROW NAME
80
WORD 0
WORD 1
BYTE 0/8
BYTE 1/9
<0>CONFIG
0
<8>MODE
<4>TINDEX
88
<8>CONFIG
1
DACFS
CNFGA
90
<8>SCALE
0
XOVER COARSE
98
<8>SCALE
1
A0
<8>OFFSET
0
<8>OFFSET
1
A8
<9>PWD
B0
B8
C0
<8>PWD
ENABLE
C8
<0>MAXROW
D0–DF
EMPTY
E0
<8>3W
CONFIG0
WORD 2
BYTE 3/B
BYTE 4/C
<4>MODULATION
VALUE
RESERVED
CNFGB
CNFGC
RESERVED
WORD 3
BYTE 5/D
<4>APC
BYTE 6/E
CNFGD
BYTE 7/F
<4>SET_IBIAS
VALUE
VALUE
RSHIFT1
RSHIFT0
VCC SCALE
TXB SCALE
RSSI FINE SCALE
RESERVED
RSSI COARSE SCALE
RESERVED
XOVER FINE
VCC OFFSET
TXB OFFSET
TXP OFFSET
RSSI FINE OFFSET
RESERVED
RSSI COARSE OFFSET
INTERNAL TEMP OFFSET*
PW1 MSW
PW1 LSW
PW2 MSW
VALUE
EMPTY
BYTE 2/A
TXP SCALE
PW2 LSW
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
PW_ENA
PW_ENB
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
TBLSELPON
<4>IMODMAX
<4>IBIASMAX
<4>DAC
<4>DAC
VALUE
VALUE
<4>INCBYTE
<4>TXCTRL5
DPC
<10>DEVICE
ID
<10>DEVICE
VER
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
RXCTRL1
RXCTRL2
SETCML
SETLOSH
TXCTRL1
TXCTRL2
TXCTRL3
TXCTRL4
SET_LOS
E8
<8>3W
CONFIG1
TXCTRL5 APC OL
TXCTRL6
TXCTRL7
RESERVED
SETLOSH_3945
SETLOSL_3945
F0
<0>3W
CONFIG2
<8>3WCTRL
<8>ADDRESS
<8>WRITE
<10>READ
<10>TXSTAT2
<10>TXSTAT1
<10>DPCSTAT
<10>RXSTAT
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
F8
EMPTY
TIMER_3945
3WSET
*The final result must be XORed with BB40h before writing to this register.
**Do not write to this register.
The access codes represent the factory default values of PW_ENA (A2h Table 02h, Register C0h) and PW_ENB (A2h Table 02h,
Register C1h).
ACCESS
CODE
Read
Access
Write
Access
<0>
See each
bit/byte
separately
<1>
<2>
<3>
<4>
<5>
<6>
<7>
<8>
<9>
<10>
<11>
All
All
All
PW2
All
N/A
PW1
PW2
N/A
PW2
All
PW2
N/A
All and
device
hardware
PW2 +
mode
bit
All
All
PW1
PW2
PW2
N/A
PW1
41
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 04h Register Map
A2h TABLE 04h (MODULATION OR TXCTRL5 LUT)
ROW
(HEX)
80–A7
WORD 0
ROW NAME
BYTE 0/8
WORD 1
BYTE 1/9
BYTE 2/A
WORD 2
BYTE 3/B
<8>MODULATION/
BYTE 4/C
WORD 3
BYTE 5/D
BYTE 6/E
BYTE 7/F
SEE TABLE DESCRIPTION
TXCTRL5
A8–EF
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
F0
<8>IMODMAX
MOD MAX LUT
MOD MAX LUT
MOD MAX LUT
MOD MAX LUT
MOD MAX LUT
MOD MAX LUT
MOD MAX LUT
MOD MAX LUT
F8
<8>MOD
OFFSET/
SEE TABLE DESCRIPTION
SET_IMOD LUT
A2h Table 05h Register Map
A2h TABLE 05h
ROW
(HEX)
ROW NAME
80–F7
EMPTY
F8
<8>ALARM
WORD 0
ENABLE
WORD 1
WORD 2
WORD 3
BYTE 0/8
BYTE 1/9
BYTE 2/A
BYTE 3/B
BYTE 4/C
BYTE 5/D
BYTE 6/E
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
BYTE 7/F
EMPTY
ALARM EN3
ALARM EN2
RESERVED
RESERVED
WARN EN3
WARN EN2
RESERVED
RESERVED
Note: A2h Table 05h is empty by default. It can be configured to contain the alarm and warning enable bytes from A2h Table 01h,
Registers F8h-FFh with the MASK bit enabled (A2h Table 02h, Register 89h). In this case A2h Table 01h will be empty.
A2h Table 06h Register Map
A2h TABLE 06h (BIAS OR APC LUT)
ROW
(HEX)
80–A7
WORD 0
ROW NAME
<8>BIAS/APC
BYTE 0/8
WORD 1
BYTE 1/9
BYTE 2/A
LUT
WORD 2
BYTE 3/B
BYTE 4/C
WORD 3
BYTE 5/D
BYTE 6/E
BYTE 7/F
SEE TABLE DESCRIPTION
A8–EF
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
F0
<8>IBIASMAX
BIAS MAX LUT
BIAS MAX LUT
BIAS MAX LUT
BIAS MAX LUT
BIAS MAX LUT
BIAS MAX LUT
BIAS MAX LUT
BIAS MAX LUT
F8
<8>BIAS/SET_IBIAS
OFF
SEE TABLE DESCRIPTION
The access codes represent the factory default values of PW_ENA (A2h Table 02h, Register C0h) and PW_ENB (A2h Table 02h,
Register C1h).
ACCESS
CODE
Read
Access
Write
Access
<0>
See each
bit/byte
separately
<1>
<2>
<3>
<4>
<5>
<6>
<7>
<8>
<9>
<10>
<11>
All
All
All
PW2
All
N/A
PW1
PW2
N/A
PW2
All
PW2
N/A
All and
device
hardware
PW2 +
mode
bit
All
All
PW1
PW2
PW2
N/A
PW1
42
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 08h Register Map
A2h TABLE 08h (INC LUT)
ROW
(HEX)
ROW NAME
WORD 0
BYTE 0/8
WORD 1
BYTE 1/9
BYTE 2/A
WORD 2
BYTE 3/B
BYTE 4/C
WORD 3
BYTE 5/D
BYTE 6/E
BYTE 7/F
80–F7
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
F8–FF
<8>INCROW
INCBYTE
INCBYTE
INCBYTE
INCBYTE
INCBYTE
INCBYTE
INCBYTE
INCBYTE
A2h Table 09h Register Map
A2h TABLE 09h (DAC OFFSET LUT)
ROW
(HEX)
ROW NAME
80–F7
F8–FF
EMPTY
<8>DAC
OFFSET
WORD 0
BYTE 0/8
WORD 1
BYTE 1/9
BYTE 2/A
WORD 2
BYTE 3/B
BYTE 4/C
WORD 3
BYTE 5/D
BYTE 6/E
BYTE 7/F
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
EMPTY
DACOFF
DACOFF
DACOFF
DACOFF
DACOFF
DACOFF
DACOFF
DACOFF
Auxiliary A0h Memory Register Map
AUXILIARY MEMORY (A0h)
ROW
(HEX)
ROW NAME
WORD 0
WORD 1
WORD 2
WORD 3
BYTE 0/8
BYTE 1/9
BYTE 2/A
BYTE 3/B
BYTE 4/C
BYTE 5/D
BYTE 6/E
BYTE 7/F
00–7F
<5>AUX
EE
EE
EE
EE
EE
EE
EE
EE
EE
80–FF
<5>AUX
EE
EE
EE
EE
EE
EE
EE
EE
EE
The access codes represent the factory default values of PW_ENA (A2h Table 02h, Register C0h) and PW_ENB (A2h Table 02h,
Register C1h).
ACCESS
CODE
Read
Access
Write
Access
<0>
See each
bit/byte
separately
<1>
<2>
<3>
<4>
<5>
<6>
<7>
<8>
<9>
<10>
<11>
All
All
All
PW2
All
N/A
PW1
PW2
N/A
PW2
All
PW2
N/A
All and
device
hardware
PW2 +
mode
bit
All
All
PW1
PW2
PW2
N/A
PW1
43
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory Register Descriptions
A2h Lower Memory, Register 00h–01h: TEMP ALARM HI
A2h Lower Memory, Register 04h–05h: TEMP WARN HI
FACTORY DEFAULT
7FFFh
READ ACCESS
All
WRITE ACCESS
PW2
MEMORY TYPE
Nonvolatile (SEE)
00h, 04h
S
26
25
24
23
22
21
20
01h, 05h
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
BIT 7
BIT 0
Temperature measurement updates above this two’s complement threshold set its corresponding alarm or
warning bit. Temperature measurement updates equal to or below this threshold clear its alarm or warning bit.
A2h Lower Memory, Register 02h–03h: TEMP ALARM LO
A2h Lower Memory, Register 06h–07h: TEMP WARN LO
FACTORY DEFAULT
8000h
READ ACCESS
All
WRITE ACCESS
PW2
MEMORY TYPE
Nonvolatile (SEE)
02h, 06h
S
26
25
24
23
22
21
20
03h, 07h
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
BIT 7
BIT 0
Temperature measurement updates below this two’s complement threshold set its corresponding alarm or
warning bit. Temperature measurement updates equal to or above this threshold clear its alarm or warning bit.
44
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 08h–09h: VCC ALARM HI
A2h Lower Memory, Register 0Ch–0Dh: VCC WARN HI
A2h Lower Memory, Register 10h–11h: TXB ALARM HI
A2h Lower Memory, Register 14h–15h: TXB WARN HI
A2h Lower Memory, Register 18h–19h: TXP ALARM HI
A2h Lower Memory, Register 1Ch–1Dh: TXP WARN HI
A2h Lower Memory, Register 20h–21h: RSSI ALARM HI
A2h Lower Memory, Register 24h–25h: RSSI WARN HI
FACTORY DEFAULT
FFFFh
READ ACCESS
All
WRITE ACCESS
PW2
MEMORY TYPE
Nonvolatile (SEE)
08h, 0Ch,
10h,14h,
18h, 1Ch,
20h, 24h
215
214
213
212
211
210
29
28
09h, 0Dh,
11h, 15h,
19h, 1Dh,
21h, 25h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
Voltage measurement updates above this unsigned threshold set its corresponding alarm or warning bit.
Voltage measurements equal to or below this threshold clear its alarm or warning bit.
45
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 0Ah–0Bh: VCC ALARM LO
A2h Lower Memory, Register 0Eh–0Fh: VCC WARN LO
A2h Lower Memory, Register 12h–13h: TXB ALARM LO
A2h Lower Memory, Register 16h–17h: TXB WARN LO
A2h Lower Memory, Register 1Ah–1Bh: TXP ALARM LO
A2h Lower Memory, Register 1Eh–1Fh: TXP WARN LO
A2h Lower Memory, Register 22h–23h: RSSI ALARM LO
A2h Lower Memory, Register 26h–27h: RSSI WARN LO
FACTORY DEFAULT
0000h
READ ACCESS
All
WRITE ACCESS
PW2
MEMORY TYPE
Nonvolatile (SEE)
0Ah, 0Eh,
12h, 16h,
1Ah, 1Eh,
22h, 26h
215
214
213
212
211
210
29
28
0Bh, 0Fh,
13h, 17h,
1Bh, 1Fh,
23h, 27h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
Voltage measurement updates below this unsigned threshold set its corresponding alarm or warning bit. Voltage
measurements equal to or above this threshold clear its alarm or warning bit.
46
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 28h–37h: EMPTY
FACTORY DEFAULT
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are empty.
A2h Lower Memory, Register 38h–5Fh: EE
38h–5Fh
FACTORY DEFAULT
00h
READ ACCESS
All
WRITE ACCESS
PW2
MEMORY TYPE
Nonvolatile (EE)
EE
EE
EE
EE
EE
EE
EE
BIT 7
EE
BIT 0
PW2 level access-controlled EEPROM.
A2h Lower Memory, Register 60h–61h: TEMP VALUE
FACTORY DEFAULT
0000h
READ ACCESS
All
WRITE ACCESS
N/A
MEMORY TYPE
Volatile
60h
S
26
25
24
23
22
21
20
61h
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
BIT 7
BIT 0
Signed two’s complement direct-to-temperature measurement.
47
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 62h–63h: VCC VALUE
A2h Lower Memory, Register 64h–65h: TXB VALUE
A2h Lower Memory, Register 66h–67h: TXP VALUE
A2h Lower Memory, Register 68h–69h: RSSI VALUE
POWER-ON VALUE
0000h
READ ACCESS
All
WRITE ACCESS
N/A
MEMORY TYPE
Volatile
62h, 64h,
66h, 68h
215
214
213
212
211
210
29
28
63h, 65h,
67h, 69h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
Left-justified unsigned voltage measurement.
A2h Lower Memory, Register 6Ah–6Dh: RESERVED
POWER-ON VALUE
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are reserved.
48
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 6Eh: STATUS
Write Access
6Eh
POWER-ON VALUE
X0XX 0XXXb
READ ACCESS
All
WRITE ACCESS
See below description
MEMORY TYPE
Volatile
N/A
All
N/A
All
All
N/A
N/A
N/A
TXDS
TXDC
TXFIS
RSELS
RESERVED
TXFOUTS
RXL
RDYB
BIT 7
BIT 0
BIT 7
TXDS: TXD status bit. Reflects the logic state of the TXD pin (read-only).
0 = TXD pin is logic-low.
1 = TXD pin is logic-high.
BIT 6
TXDC: TXD software control bit. This bit allows for software control that is identical to the TXD pin.
See the section on TXD for further information. Its value is wired-ORed with the logic value of the
TXD pin (writable by all users).
0 = (Default)
1 = Forces the device into a TXD state regardless of the value of the TXD pin.
BIT 5
TXFIS: Reflects the status of the TXF pin. The status will also include any inversion caused by the
INVTXFI bit (read-only).
0 = TXF pin is low (after any inversion caused by the INVTXFI bit).
1 = TXF pin is high (after any inversion caused by the INVTXFI bit).
BIT 4
RSELS: RSEL status bit. Reflects the logic state of the RSEL pin (read-only).
0 = RSEL pin is logic-low.
1 = RSEL pin is logic-high.
BIT 3
RESERVED
BIT 2
TXFOUTS: TXFOUT status. Indicates the state the open drain output is attempting to achieve.
0 = TXFOUT is pulling low.
1 = TXFOUT is high impedance.
BIT 1
RXL: Reflects the driven state of the LOS pin (read-only).
0 = LOS pin is driven low.
1 = LOS pin is pulled high.
BIT 0
RDYB: Ready bar.
0 = VCC is above POA.
1 = VCC is below POA and/or too low to communicate over the I2C bus.
49
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 6Fh: UPDATE
6Fh
POWER-ON VALUE
00h
READ ACCESS
All
WRITE ACCESS
All and DS1886 Hardware
MEMORY TYPE
Volatile
TEMP RDY
VCC RDY
TXB RDY
TXP RDY
RSSI RDY
RSSIR
POW_LEV1
BIT 7
BITS 7:3
BIT 2
BITS 1:0
POW_LEV0
BIT 0
Update of completed conversions. At power-on, these bits are cleared and are set as each conversion is
completed. These bits can be cleared so that a completion of a new conversion is verified.
RSSIR: RSSI range. Reports the range used for conversion update of RSSI.
0 = Fine range is the reported value.
1 = Coarse range is the reported value.
POW_LEV[1:0]: Power level. These bits are active only when the DS1863_MODE bit in A2h Table 02h,
Register 8Dh (CNFGD) is 0. These bits change the MAX3710 bits KRMD[2:1] to adjust the MD input
impedance. See the Power Leveling section for more details.
50
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 70h: ALARM3
70h
POWER-ON VALUE
10h
READ ACCESS
All
WRITE ACCESS
N/A
MEMORY TYPE
Volatile
TEMP HI
TEMP LO
VCC HI
VCC LO
TXB HI
TXB LO
BIT 7
TXP HI
TXP LO
BIT 0
BIT 7
TEMP HI: High alarm status for temperature measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 6
TEMP LO: Low Alarm status for temperature measurement.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
BIT 5
VCC HI: High alarm status for VCC measurement.
0 = (Default) Last measurement was equal to or below threshold setting
1 = Last measurement was above threshold setting.
BIT 4
VCC LO: Low alarm status for VCC measurement. This bit is set when the VCC supply is below the POA
trip point value. It clears itself when a VCC measurement is completed and the value is above the low
threshold.
0 = Last measurement was equal to or above threshold setting.
1 = (Default) Last measurement was below threshold setting.
BIT 3
TXB HI: High alarm status for TXB measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 2
TXB LO: Low alarm status for TXB measurement.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
BIT 1
TXP HI: High alarm status for TXP measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 0
TXP LO: Low alarm status for TXP measurement.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
51
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 71h: ALARM2
71h
POWER-ON VALUE
00h
READ ACCESS
All
WRITE ACCESS
N/A
MEMORY TYPE
Volatile
RSSI HI
RSSI LO
RESERVED
RESERVED
RESERVED
IN1S
RESERVED
BIT 7
BIT 0
BIT 7
RSSI HI: High alarm status for RSSI measurement. A TXD event does not clear this alarm.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 6
RSSI LO: Low alarm status for RSSI measurement. A TXD event does not clear this alarm.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
BITS 5:3
TXFINT
RESERVED
BIT 2
IN1S: IN1 status bit. Reflects the logic state of the IN1 pin (read-only).
0 = IN1 pin is logic-low.
1 = IN1 pin is logic-high.
BIT 1
RESERVED
BIT 0
TXFINT: TXFOUT interrupt. This bit is the wired-ORed logic of all alarms and warnings wired-ANDed with
their corresponding enable bits. The enable bits are found in A2h Table 01h/05h, Registers F8–FFh.
A2h Lower Memory, Register 72h–73h: RESERVED
POWER-ON VALUE
00h
READ ACCESS
All
WRITE ACCESS
N/A
MEMORY TYPE
These registers are reserved.
52
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 74h: WARN3
74h
POWER-ON VALUE
10h
READ ACCESS
All
WRITE ACCESS
N/A
MEMORY TYPE
Volatile
TEMP HI
TEMP LO
VCC HI
VCC LO
TXB HI
TXB LO
BIT 7
TXP HI
TXP LO
BIT 0
BIT 7
TEMP HI: High warning status for temperature measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 6
TEMP LO: Low warning status for temperature measurement.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
BIT 5
VCC HI: High warning status for VCC measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 4
VCC LO: Low warning status for VCC measurement. This bit is set when the VCC supply is below the POA
trip point value. It clears itself when a VCC measurement is completed and the value is above the low
threshold.
0 = Last measurement was equal to or above threshold setting.
1 = (Default) Last measurement was below threshold setting.
BIT 3
TXB HI: High warning status for TXB measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 2
TXB LO: Low warning status for TXB measurement.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
BIT 1
TXP HI: High warning status for TXP measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 0
TXP LO: Low warning status for TXP measurement.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
53
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 75h: WARN2
75h
POWER-ON VALUE
00h
READ ACCESS
All
WRITE ACCESS
N/A
MEMORY TYPE
Volatile
RSSI HI
RSSI LO
RESERVED
RESERVED
RESERVED
RESERVED
BIT 7
RESERVED
BIT 0
BIT 7
RSSI HI: High warning status for RSSI measurement.
0 = (Default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 6
RSSI LO: Low warning status for RSSI measurement.
0 = (Default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
BITS 5:0
RESERVED
RESERVED
A2h Lower Memory, Register 76h–7Ah: RESERVED
POWER-ON VALUE
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are reserved.
54
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Lower Memory, Register 7Bh–7Eh: PASSWORD ENTRY (PWE)
POWER-ON VALUE
FFFF FFFFh
READ ACCESS
N/A
WRITE ACCESS
ALL
MEMORY TYPE
Volatile
7Bh
231
230
229
228
227
226
225
224
7Ch
223
222
221
220
219
218
217
216
7Dh
215
214
213
212
211
210
29
28
7Eh
27
26
25
24
23
22
21
20
BIT 7
BIT 0
There are two passwords for the DS1886. Each password is 4 bytes long. The lower level password (PW1) will have all the
access of a normal user plus those made available with PW1. The higher level password (PW2) will have all of the access
of PW1 plus those made available with PW2. The values of the passwords reside in EEPROM inside of PW2 memory. At
power up, all PWE bits are set to 1. All reads at this location are 0.
A2h Lower Memory, Register 7Fh: TBL SEL
7Fh
POWER-ON VALUE
TBLSELPON (A2h Table 02h, Register C7h).
READ ACCESS
All
WRITE ACCESS
All
MEMORY TYPE
Volatile
27
BIT 7
26
25
24
23
22
21
20
BIT 0
The upper memory tables of the DS1886 are accessible by writing the desired table value in this register. The power-on
value of this register is defined by the value written to TBLSELPON (A2h Table 02, Register C7h).
55
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 01h Register Descriptions
A2h Table 05h can be configured to contain the alarm and warning enable bytes from A2h Table 01h, Registers F8h–
FFh with the MASK bit enabled (A2h Table 02h, Register 89h). In this case the corresponding bytes in A2h Table 01h
are empty.
A2h Table 01h, Register 80h–BFh: EEPROM
80h–BFh
POWER-ON VALUE
00h
READ ACCESS
PW2 or (PW1 and RWTBL1A) or (PW1 and RTBL1A)
WRITE ACCESS
PW2 or (PW1 and RWTBL1A)
MEMORY TYPE
Nonvolatile (EE)
EE
EE
EE
EE
EE
EE
EE
BIT 7
EE
BIT 0
EEPROM for PW1 and/or PW2 level access.
A2h Table 01h, Register C0h–F7h: EEPROM
C0h–F7h
POWER-ON VALUE
00h
READ ACCESS
PW2 or (PW1 and RWTBL1B) or (PW1 and RTBL1B)
WRITE ACCESS
PW2 or (PW1 and RWTBL1B)
MEMORY TYPE
Nonvolatile (EE)
EE
EE
EE
BIT 7
EE
EE
EE
EE
EE
BIT 0
EEPROM for PW1 and/or PW2 level access.
56
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 01h, Register F8h: ALARM EN3
F8h
POWER-ON VALUE
00h
READ ACCESS
PW2 or (PW1 and RWTBL1C) or (PW1 and RTBL1C)
WRITE ACCESS
PW2 or (PW1 and RWTBL1C)
MEMORY TYPE
Nonvolatile (SEE)
TEMP HI
TEMP LO
VCC HI
VCC LO
BIT 7
TXB HI
TXB LO
TXP HI
TXP LO
BIT 0
Layout is identical to ALARM3 in Lower Memory, Register 70h. Enables alarms to create TXFINT (Lower Memory,
Register 71h) logic. The MASK bit (A2h Table 02h, Register 89h) determines whether this memory exists in A2h
Table 01h or 05h. When in A2h Table 05h, this location at A2h Table 01h becomes EE.
BIT 7
TEMP HI:
0 = Disables interrupt from TEMP HI alarm.
1 = Enables interrupt from TEMP HI alarm.
BIT 6
TEMP LO:
0 = Disables interrupt from TEMP LO alarm.
1 = Enables interrupt from TEMP LO alarm.
BIT 5
VCC HI:
0 = Disables interrupt from VCC HI alarm.
1 = Enables interrupt from VCC HI alarm.
BIT 4
VCC LO:
0 = Disables interrupt from VCC LO alarm.
1 = Enables interrupt from VCC LO alarm.
BIT 3
TXB HI:
0 = Disables interrupt from TXB HI alarm.
1 = Enables interrupt from TXB HI alarm.
BIT 2
TXB LO:
0 = Disables interrupt from TXB LO alarm.
1 = Enables interrupt from TXB LO alarm.
BIT 1
TXP HI:
0 = Disables interrupt from TXP HI alarm.
1 = Enables interrupt from TXP HI alarm.
BIT 0
TXP LO:
0 = Disables interrupt from TXP LO alarm.
1 = Enables interrupt from TXP LO alarm.
57
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 01h, Register F9h: ALARM EN2
F9h
POWER-ON VALUE
00h
READ ACCESS
PW2 or (PW1 and RWTBL1C) or (PW1 and RTBL1C)
WRITE ACCESS
PW2 or (PW1 and RWTBL1C)
MEMORY TYPE
Nonvolatile (SEE)
RSSI HI
RSSI LO
RESERVED
RESERVED
RESERVED
IN1EN
RESERVED
BIT 7
RESERVED
BIT 0
Layout is identical to ALARM2 in Lower Memory, Register 71h. Enables alarms to create TXFINT (Lower Memory,
Register 71h) logic. The MASK bit (A2h Table 02h, Register 89h) determines whether this memory exists in A2h Table
01h or 05h. When in A2h Table 05h, this location at A2h Table 01h becomes EE.
BIT 7
RSSI HI:
0 = Disables interrupt from RSSI HI alarm.
1 = Enables interrupt from RSSI HI alarm.
BIT 6
RSSI LO:
0 = Disables interrupt from RSSI LO alarm.
1 = Enables interrupt from RSSI LO alarm.
BITS 5:3
RESERVED
BIT 2
IN1EN
0 = Disable interrupt due to IN1 input pin.
1 = Enable interrupt due to IN1 input pin.
BIT 0
RESERVED
A2h Table 01h, Register FAh–FBh: RESERVED
POWER-ON VALUE
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
These registers are reserved. When in A2h Table 05h, this location at A2h Table 01h becomes EE.
58
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 01h, Register FCh: WARN EN3
FCh
POWER-ON VALUE
00h
READ ACCESS
PW2 or (PW1 and RWTBL1C) or (PW1 and RTBL1C)
WRITE ACCESS
PW2 or (PW1 and RWTBL1C)
MEMORY TYPE
Nonvolatile (SEE)
TEMP HI
TEMP LO
VCC HI
VCC LO
TXB HI
BIT 7
TXB LO
TXP HI
TXP LO
BIT 0
Layout is identical to WARN3 in Lower Memory, Register 74h. Enables warnings to create TXFINT (Lower Memory,
Register 71h) logic. The MASK bit (A2h Table 02h, Register 89h) determines whether this memory exists in A2h
Table 01h or 05h. When in A2h Table 05h, this location at A2h Table 01h becomes EE.
BIT 7
TEMP HI:
0 = Disables interrupt from TEMP HI warning.
1 = Enables interrupt from TEMP HI warning.
BIT 6
TEMP LO:
0 = Disables interrupt from TEMP LO warning.
1 = Enables interrupt from TEMP LO warning.
BIT 5
VCC HI:
0 = Disables interrupt from VCC HI warning.
1 = Enables interrupt from VCC HI warning.
BIT 4
VCC LO:
0 = Disables interrupt from VCC LO warning.
1 = Enables interrupt from VCC LO warning.
BIT 3
TXB HI:
0 = Disables interrupt from TXB HI warning.
1 = Enables interrupt from TXB HI warning.
BIT 2
TXB LO:
0 = Disables interrupt from TXB LO warning.
1 = Enables interrupt from TXB LO warning.
BIT 1
TXP HI:
0 = Disables interrupt from TXP HI warning.
1 = Enables interrupt from TXP HI warning.
BIT 0
TXP LO:
0 = Disables interrupt from TXP LO warning.
1 = Enables interrupt from TXP LO warning.
59
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 01h, Register FDh: WARN EN2
FDh
POWER-ON VALUE
00h
READ ACCESS
PW2 or (PW1 and RWTBL1C) or (PW1 and RTBL1C)
WRITE ACCESS
PW2 or (PW1 and RWTBL1C)
MEMORY TYPE
Nonvolatile (SEE)
RSSI HI
RSSI LO
RESERVED
RESERVED
BIT 7
RESERVED
RESERVED
RESERVED
RESERVED
BIT 0
Layout is identical to WARN2 in Lower Memory, Register 75h. Enables warnings to create TXFINT (Lower Memory,
Register 71h) logic. The MASK bit (A2h Table 02h, Register 89h) determines whether this memory exists in A2h Table
01h or 05h. When in A2h Table 05h, this location at A2h Table 01h becomes EE.
BIT 7
RSSI HI:
0 = Disables interrupt from RSSI HI warning.
1 = Enables interrupt from RSSI HI warning.
BIT 6
RSSI LO:
0 = Disables interrupt from RSSI LO warning.
1 = Enables interrupt from RSSI LO warning.
BITS 5:0
RESERVED
A2h Table 01h, Register FEh–FFh: RESERVED OR EE
POWER-ON VALUE
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
These registers are reserved.
60
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h Register Descriptions
A2h Table 02h, Register 80h: MODE
POWER-ON VALUE
READ ACCESS
WRITE ACCESS
MEMORY TYPE
80h
SEEB
7Fh
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
PW2 or (PW1 and RWTBL246)
Volatile
INCROW
LUT EN
TXCTRL5 LUT
EN
BIAS LUT
EN
AEN
MOD LUT
EN
BIT 7
APC LUT
EN
DAC LUT
EN
BIT 0
BIT 7
SEEB:
0 = (Default) Enables EEPROM writes to SEE bytes.
1 = Disables EEPROM writes to SEE bytes during configuration, so that the configuration of the part is not delayed
by the EE cycle time. Once the values are known, write this bit to a 0 and write the SEE locations again for data
to be written to the EEPROM.
BIT 6
INCROW LUT EN:
0 = INCROW register is controlled by the user. The INCROW register value is written with the use of the 3-wire
interface. This allows users to interactively test their modules by writing the INCROW register value. In APC loop
mode, only BIASINC[3:0] is updated. In DPC loop mode, both BIASINC[3:0] and MODINC[3:0] are updated.
1 = (Default) Enables auto control for the INCROW register.
BIT 5
TXCTRL5 LUT EN:
0 = TXCTRL5 DPC register is writable by the user and the LUT recalls are disabled.
1 = (Default) Enables auto control of the LUT for TXCTRL5.
BIT 4
BIAS LUT EN:
0 = SET_IBIAS and IBIASMAX registers are controlled by the user. The SET_IBIAS and IBIASMAX value is
written with the use of the 3-wire interface. This allows the user to interactively test their modules by directly
controlling the SET_IBIAS and IBIASMAX.
1 = (Default) Enables LUT control of the SET_IBIAS and IBIASMAX.
BIT 3
AEN:
0 = The temperature-calculated index value TINDEX is writable by the user and the updates of calculated
indexes are disabled. This allows users to interactively test their modules by controlling the indexing for the
look up tables. The recalled values from the LUTs appear in the DAC registers after the next completion of a
temperature conversion.
1 = (Default) The internal temperature sensor determines the value of TINDEX
BIT 2
MOD LUT EN:
0 = MODULATION VALUE and IMODMAX registers are controlled by the user. The MODULATION VALUE and
IMODMAX values are written with the use of the 3-wire interface. This allows users to interactively test their
modules by directly controlling the MODULATION VALUE and IMODMAX.
1 = (Default) Enables LUT control of MODULATION VALUE and IMODMAX.
BIT 1
APC LUT EN:
0 = APC VALUE register is controlled by the user. The APC VALUE value is written with the use of the 3-wire
interface. This allows users to interactively test their modules by directly controlling the APC VALUE register.
1 = (Default) Enables LUT control of APC VALUE.
BIT 0
DAC LUT EN: See the Delta-Sigma Output and Reference section for details.
0 = DAC VALUE is writable by the user and the DAC formula calculation disabled. This allows users to
interactively test their modules by writing the values for DAC. The output is updated with the new value at the
end of the write cycle. The I2C STOP condition is the end of the write cycle.
1 = (Default) Enables auto control of the LUT for DAC VALUE.
61
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 81h: Temperature Index (TINDEX)
81h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
(PW2 and AEN = 0) or (PW1 and RWTBL246 and AEN = 0)
MEMORY TYPE
Volatile
27
26
25
24
23
22
21
BIT 7
20
BIT 0
Holds the calculated index based on the temperature measurement. This index is used for the address during lookup
of Tables 04h, 06h, and 08h. Temperature measurements below -40NC or above +102NC are clamped to 80h and
C7h, respectively. The calculation of TINDEX is as follows:
=
TINDEX
Temp_Value + 40°C
+ 80h
2°C
For the temperature-indexed LUTs, the index used during the lookup function for each table is as follows:
A2h Table 04h
(MOD)
1
TINDEX6
TINDEX5
TINDEX4
TINDEX3
TINDEX2
TINDEX1
TINDEX0
A2h Table 06h
(APC)
1
0
TINDEX6
TINDEX5
TINDEX4
TINDEX3
TINDEX2
TINDEX1
A2h Table 02h, Register 82h–83h: MODULATION VALUE
FACTORY DEFAULT
0000h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
(PW2 and MOD LUT EN = 0) or (PW1 and RWTBL246 and MOD LUT EN = 0)
MEMORY TYPE
Volatile
82h
0
0
0
0
0
0
0
28
83h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
The digital value used for MOD and recalled from A2h Table 04h at the adjusted memory address found in TINDEX.
This register is updated at the end of the temperature conversion.
A2h Table 02h, Register 84h: RESERVED
FACTORY DEFAULT
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
This register is reserved.
62
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 85h: APC VALUE
85h
FACTORY DEFAULT
0000h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
(PW2 and APC LUT EN = 0) or (PW1 and RWTBL246 and APC LUT EN = 0)
MEMORY TYPE
Volatile
27
26
25
24
23
22
21
BIT 7
20
BIT 0
The digital value used for APC and recalled from A2h Table 06h in the APC and dual-closed-loop mode at the
adjusted memory address found in TINDEX. This register is updated at the end of the temperature conversion.
A2h Table 02h, Register 86h–87h: SET_IBIAS VALUE
FACTORY DEFAULT
0000h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
(PW2 and APC LUT EN = 0) or (PW1 and RWTBL246 and APC LUT EN = 0)
MEMORY TYPE
Volatile
86h
0
0
0
0
0
0
29
28
87h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
The digital value used for BIAS and recalled from A2h Table 06h in the open-loop mode at the adjusted memory
address found in TINDEX. This register is updated at the end of the temperature conversion.
A2h Table 02h, Register 88h: DACFS
88h
FACTORY DEFAULT
FFh
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
29
BIT 7
28
27
26
25
24
23
22
BIT 0
DACFS sets the slope of the DAC’s temperature compensation. In conjunction with DAC OFFSET and TINDEX,
this allows the DAC to create an output that is linearly dependent on temperature. For further details see the DeltaSigma Output and Reference section.
63
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 89h: CNFGA
89h
FACTORY DEFAULT
82h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
LOSC
RESERVED
INV LOS
RESERVED
MASK
RESERVED
BIT 7
BURST_MODE
INVTXFI
BIT 0
BIT 7
LOSC: Enables LOSOUT due to input pin LOS.
0 = LOSOUT is affected by the LOS input.
1 = LOSOUT is not affected by changed in the LOS input.
BIT 6
RESERVED
BIT 5
INV LOS: Inverts the buffered input pin LOS to output pin LOSOUT.
0 = Noninverted LOS to LOSOUT pin.
1 = Inverted LOS to LOSOUT pin.
BIT 4
RESERVED
BIT 3
MASK:
0 = Alarm enable row exists at A2h Table 01h, Registers F8h–FFh. A2h Table 05h, Registers F8h–
FFh are empty.
1 = Alarm enable row exists at A2h Table 05h, Registers F8h–FFh. A2h Table 01h, Registers F8h–
FFh are empty.
BIT 2
RESERVED
BIT 1
BURST_MODE:
0 = TXP is derived from the TXMON input.
1 = TXP is calculated from MD0 and MD1, which are read from the MAX3710 through the 3-wire
interface.
BIT 0
INVTXFI: Allow for inversion of signal driven by TXF input pin.
0 = (Default) TXF signal is not inverted.
1 = TXF signal is inverted.
64
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 8Ah: CNFGB
8Ah
FACTORY DEFAULT
40h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
RESERVED
RESERVED
BIASMOD_RSTEN
RESERVED
RESERVED
ALATCH
RESERVED
BIT 7
WLATCH
BIT 0
BIT 7
RESERVED
BIT 6
BIASMOD_RSTEN:
0 = BIASREG and MODREG when set to 0 do not cause a restart.
1 = (Default) When BIASREG = 0 or MODREG = 0 in the MAX3710, the TXCTRL6 restart and soft_
restart bits are set to 1.
BITS 5:3
RESERVED
BIT 2
ALATCH: ADC alarm’s comparison LATCH. A2h Table 01h, Registers 70h–71h.
0 = ADC alarm and flags reflect the status of the last comparison.
1 = ADC alarm flags remain set.
BIT 1
RESERVED
BIT 0
WLATCH: ADC warning’s comparison LATCH. A2h Table 01h, Registers 74h–75h.
0 = ADC warning flags reflect the status of the last comparison.
1 = ADC warning flags remain set.
65
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 8Bh: CNFGC
8Bh
FACTORY DEFAULT
10h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
XOVEREN
RESERVED
TXDM3
BIASMODOVFL_FLT
TXDFLT
TXDIO
RSSI_FC
RSSI_FF
BIT 7
BIT 0
BIT 7
XOVEREN: Enables RSSI conversion to use the XOVER (A2h Table 02h, Register 90h–91h) value
during RSSI conversions.
0 = Uses hysteresis for linear RSSI measurements.
1 = XOVER value is enabled for nonlinear RSSI measurements.
BIT 6
RESERVED
BIT 5
TXDM3: Enables TXD to reset alarms and warnings associated to RSSI during a TXD event.
0 = TXD event has no affect on the RSSI alarms and warnings.
1 = RSSI alarms and warnings are reset during a TXD event.
BIT 4
BIASMODOVFL_FLT:
0 = IBIASOVFL and IMODOVFL bits in the DPCSTAT register in the MAX3710 have no affect on
TXFOUT.
1 = IBIASOVFL or IMODOVFL bits when set to 1 in the DPCSTAT register in the MAX3710 cause the
TXFOUT pin to be set to 1.
BIT 3
TXDFLT: See Figure 10.
0 = TXF pin has no affect on TXDOUT.
1 = TXF pin is enabled and ORed with other possible signals to create TXDOUT.
BIT 2
TXDIO: See Figure 10.
0 = (Default) TXD input signal is enabled and ORed with other possible signals to create TXDOUT.
1 = TXD input signal has no affect on TXDOUT.
BITS 1:0
RSSI_FC and RSSI_FF: RSSI force coarse and RSSI force fine. Control bits for RSSI mode of
operation on the RSSI conversion.
00b = (Default) Normal RSSI mode of operation.
01b = The fine settings of scale and offset are used for RSSI conversions.
10b = The coarse settings of scale and offset are used for RSSI conversions.
11b = Normal RSSI mode of operation.
A2h Table 02h, Register 8Ch: RESERVED
POWER-ON VALUE
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
This register is reserved.
66
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 8Dh: CNFGD
8Dh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
INV_DAC
RESERVED
RESERVED
RESERVED
DS1863_MODE
POW_LEV_DS1863
BIT 7
BIT 7
BITS 6:4
BIT 3
BIT 0
INV_DAC:
0 = DAC output is inverted.
1 = DAC output is not inverted.
RESERVED
DS1863_MODE:
0 = Normal operation. Power leveling defined in A2h Lower Memory, Register 6Fh.
1 = DS1863 mode. This mode is usually used for systems upgrading from the DS1863. In this mode,
KRMD[2:0] in the MAX3710 is directly written to by the POW_LEV_DS1863 bits.
POW_LEV_DS1863[2:0]
POWER LEVEL (dB)
000
0
001
0
BITS 2:0
010
0
011
-3
100
-3
101
-3
110
-6
111
-6
A2h Table 02h, Register 8Eh: RIGHT-SHIFT1 (RSHIFT1)
8Eh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
RESERVED
BIT 7
TXB2
TXB1
TXB0
RESERVED
TXP2
TXP1
TXP0
BIT 0
Allows for right-shifting the final answer of TXB and TXP voltage measurements. This allows for scaling the
measurements to the smallest full-scale voltage and then right-shifting the final result so the reading is weighted to
the correct LSB.
67
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 8Fh: RIGHT-SHIFT0 (RSHIFT0)
8Fh
FACTORY DEFAULT
30h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
RESERVED
RSSIF2
RSSIF1
RSSIF0
RESERVED
RSSIC2
RSSIC1
BIT 7
RSSIC0
BIT 0
Allows for right-shifting the final answer of RSSI fine and coarse voltage measurements. This allows for scaling the
measurements to the smallest full-scale voltage and then right-shifting the final result so the reading is weighted to
the correct LSB.
A2h Table 02h, Register 90h–91h: XOVER COARSE
90h
91h
FACTORY DEFAULT
0000h
READ ACCESS
PW2 or (PW1 and RWTBL2) or (PW1 and RTBL2)
WRITE ACCESS
PW2 or (PW1 and RWTBL2)
MEMORY TYPE
Nonvolatile (SEE)
215
214
213
212
211
210
29
27
26
25
24
23
22
21
BIT 7
28
0
BIT 0
Defines the crossover value for RSSI measurements of nonlinear inputs when XOVEREN is set to a 1 (A2h Table
02h, Register 8Bh). RSSI coarse conversion results (before right-shifting) less than this register are clamped to the
value of this register.
68
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register 92h–93h: VCC SCALE
A2h Table 02h, Register 94h–95h: TXB SCALE
A2h Table 02h, Register 96h–97h: TXP SCALE
A2h Table 02h, Register 98h–99h: RSSI FINE SCALE
A2h Table 02h, Register 9Ah–9Bh: RESERVED
A2h Table 02h, Register 9Ch–9Dh: RSSI COARSE SCALE
FACTORY CALIBRATED
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
92h, 94h,
96h, 98h,
9Ch
215
214
213
212
211
210
29
28
93h, 95h,
97h, 99h,
9Dh
27
26
25
24
23
22
21
20
BIT 7
BIT 0
Controls the scaling or gain of the full-scale voltage measurements. The factory-calibrated value produces a fullscale voltage of 6.5536V for VCC; 2.5V for TXB, TXP, and MON4; and 0.3125V for RSSI fine.
A2h Table 02h, Register 9Eh–9Fh: RESERVED
FACTORY DEFAULT
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
These registers are reserved.
69
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register A0h–A1h: XOVER FINE
FACTORY DEFAULT
FFFFh
READ ACCESS
PW2 or (PW1 and RWTBL2) or (PW1 and RTBL2)
WRITE ACCESS
PW2 or (PW1 and RWTBL2)
MEMORY TYPE
Nonvolatile (SEE)
A0h
215
214
213
212
211
210
29
28
A1h
27
26
25
24
23
22
21
0
BIT 7
BIT 0
Defines the crossover value for RSSI measurements of nonlinear inputs when XOVEREN is set to 1 (A2h Table
02h, Register 8Bh). RSSI fine conversion results (before right-shifting) greater than this register require a RSSI
coarse conversion.
A2h Table 02h, Register A2h–A3h: VCC OFFSET
A2h Table 02h, Register A4h–A5h: TXB OFFSET
A2h Table 02h, Register A6h–A7h: TXP OFFSET
A2h Table 02h, Register A8h–A9h: RSSI FINE OFFSET
A2h Table 02h, Register AAh–ABh: RESERVED
A2h Table 02h, Register ACh–ADh: RSSI COARSE OFFSET
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
A2h, A4h,
A6h, A8h,
ACh
S
215
214
213
212
211
210
29
A3h, A5h,
A7h, A9h,
ADh
28
27
26
25
24
23
22
21
BIT 7
BIT 0
Allows for offset control of these voltage measurements if desired. This number is two’s complement.
70
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register AEh–AFh: INTERNAL TEMP OFFSET
FACTORY CALIBRATED
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
AEh
S
28
27
26
25
24
23
22
AFh
21
20
2-1
2-2
2-3
2-4
2-5
2-6
BIT 7
BIT 0
Allows for offset control of temp measurement if desired. The final result must be XORed with BB40h before writing
to this register. Factory calibration contains the desired value for a reading in degrees Celsius.
A2h Table 02h, Register B0h–B3h: PW1
FACTORY DEFAULT
FFFF FFFFh
READ ACCESS
N/A
WRITE ACCESS
PW2 or (PW1 and WPW1)
MEMORY TYPE
Nonvolatile (SEE)
B0h
231
230
229
228
227
226
225
224
B1h
223
222
221
220
219
218
217
216
B2h
215
214
213
212
211
210
29
28
B3h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
The PWE value is compared against the value written to this location to enable PW1 access. At power-on, the
PWE value is set to all ones. Thus, writing these bytes to all ones grants PW1 access on power-on without writing
the password entry. All reads of this register are 00h.
71
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register B4h–B7h: PW2
FACTORY DEFAULT
FFFF FFFFh
READ ACCESS
N/A
WRITE ACCESS
PW2
MEMORY TYPE
Nonvolatile (SEE)
B4h
231
230
229
228
227
226
225
224
B5h
223
222
221
220
219
218
217
216
B6h
215
214
213
212
211
210
29
28
B7h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
The PWE value is compared against the value written to this location to enable PW2 access. At power-on, the PWE
value is set to all ones. Thus, writing these bytes to all ones grants PW2 access on power-on without writing the
password entry. All reads of this register are 00h.
A2h Table 02h, Register B8h–BFh: EMPTY
FACTORY DEFAULT
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are empty.
72
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register C0h: PW_ENA
C0h
FACTORY DEFAULT
10h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
RWTBL89
RWTBL1C
RWTBL2
RWTBL1A
RWTBL1B
WA2
LOWER
WAUXA
BIT 7
WAUXB
BIT 0
BIT 7
RWTBL89: Tables 08h–09h.
0 = (Default) read and write access for PW2 only.
1 = Read and write access for both PW1 and PW2.
BIT 6
RWTBL1C: A2h Table 01h or 05h bytes F8–FFh. Table address is dependent on MASK bit (A2h
Table 02h, Register 89h).
0 = (Default) read and write access for PW2 only.
1 = Read and write access for both PW1 and PW2.
BIT 5
RWTBL2: Table 02h except for PW1 value locations (A2h Table 02h, Registers B0h–B3h).
0 = (Default) read and write access for PW2 only.
1 = Read and write access for both PW1 and PW2.
BIT 4
RWTBL1A: Read and write A2h Table 01h, Registers 80h–BFh.
0 = Read and write access for PW2 only.
1 = (Default) read and write access for both PW1 and PW2.
BIT 3
RWTBL1B: Read and write A2h Table 01h, Registers C0h–F7h.
0 = (Default) read and write access for PW2 only.
1 = Read and write access for both PW1 and PW2.
BIT 2
WA2 LOWER: Write lower memory bytes 00h–5Fh in main memory. All users can read this area.
0 = (Default) Write access for PW2 only.
1 = Write access for both PW1 and PW2.
BIT 1
WAUXA: Write auxiliary memory, Registers 00h–7Fh. All users can read this area (see also A2h
Table 02h, Register C1h, PW_ENB).
0 = (Default) Write access for PW2 only.
1 = Write access for both PW1 and PW2.
BIT 0
WAUXB: Write auxiliary memory, Registers 80h–FFh. All users can read this area (see also A2h
Table 02h, Register C1h, PW_ENB).
0 = (Default) Write access for PW2 only.
1 = Write access for both PW1 and PW2.
73
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register C1h: PW_ENB
C1h
FACTORY DEFAULT
03h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
RWTBL46
RTBL1C
RTBL2
RTBL1A
RTBL1B
BIT 7
WPW1
WAUXAU
WAUXBU
BIT 0
BIT 7
RWTBL46: Read and write Tables 04h and 06h.
0 = (Default) Read and write access for PW2 only.
1 = Read and write access for both PW1 and PW2.
BIT 6
RTBL1C: Read A2h Table 01h or A2h Table 05h, Registers F8h–FFh. Table address is dependent
on the MASK bit (A2h Table 02h, Register 89h).
0 = (Default) Read access for PW2 only.
1 = Read access for both PW1 and PW2.
BIT 5
RTBL2: Read A2h Table 02h except for PW1 value locations (A2h Table 02h, Registers B0h–B3h).
0 = (Default) Read access for PW2 only.
1 = Read access for both PW1 and PW2.
BIT 4
RTBL1A: Read A2h Table 01h, Registers 80h–BFh.
0 = (Default) read access for PW2 only.
1 = Read access for both PW1 and PW2.
BIT 3
RTBL1B: Read A2h Table 01h, Registers C0h-F7h.
0 = (Default) read access for PW2 only.
1 = Read access for both PW1 and PW2.
BIT 2
WPW1: Write register PW1 (A2h Table 02h, Registers B0h–B3h). For security purposes these
registers are not readable.
0 = (Default) Write access for PW2 only.
1 = Write access for both PW1 and PW2.
BIT 1
WAUXAU: Write auxiliary memory, Registers 00h–7Fh. All users can read this area (see also A2h
Table 02h, Register C0h, PW_ENA).
0 = Write access for PW2 only.
1 = (Default) Write access for user, PW1, and PW2.
BIT 0
WAUXBU: Write auxiliary memory, Registers 80h–FFh. All users can read this area (see also A2h
Table 02h, Register C0h, PW_ENA)
0 = Write access for PW2 only.
1 = (Default) Write access for user, PW1, and PW2.
74
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register C2h–C6h: RESERVED
FACTORY DEFAULT
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
These registers are reserved.
A2h Table 02h, Register C7h: TBLSELPON
C7h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
Chooses the initial value for the TBL SEL byte (Lower Memory, Register 7Fh) at power-on.
A2h Table 02h, Register C8h–C9h: DAC VALUE
FACTORY DEFAULT
0000h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
(PW2 and BIAS LUT EN = 0) or (PW1 and RWTBL246 and BIAS LUT EN = 0)
MEMORY TYPE
Volatile
C8h
0
0
0
0
0
0
29
28
C9h
27
26
25
24
23
22
21
20
BIT 7
BIT 0
Value written to DAC when DAC_EN = 0, or calculated using the formula stated in the Delta-Sigma Output and
Reference section.
75
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register CAh: INCBYTE
CAh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
(PW2 and BIAS LUT EN = 0) or (PW1 and RWTBL246 and BIAS LUT EN = 0)
MEMORY TYPE
Volatile
23
22
21
20
23
22
21
BIT 7
20
BIT 0
7:4: Value written to MAX3710 BIASINC[3:0] from LUT. This must be set to 0 in open-loop mode.
3:0: Value written to MAX3710 MODINC[3:0] from LUT. This must be set to 0 in open-loop mode and APC mode.
A2h Table 02h, Register CBh: TXCTRL5 DPC
CBh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
(PW2 and APC LUT EN = 0) or (PW1 and RWTBL246 and APC LUT EN = 0)
MEMORY TYPE
Volatile
27
26
25
24
23
22
21
BIT 7
20
BIT 0
Value written to MAX3710 TXCTRL5 from the TXCTRL5 LUT. The TXCTRL5 LUT is only active during the dual
closed loop mode. For open loop and APC loop mode, see Register E8h.
A2h Table 02h, Register CCh: IMODMAX
CCh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Volatile
28
27
26
25
BIT 7
24
23
22
21
BIT 0
Value written to MAX3710 IMODMAX from the MOD MAX LUT.
76
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register CDh: IBIASMAX
CDh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Volatile
29
28
27
26
25
24
23
BIT 7
22
BIT 0
Value written to MAX3710 IBIASMAX from the BIAS MAX LUT.
A2h Table 02h, Register CEh: DEVICE ID
CEh
FACTORY DEFAULT
86h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
N/A
MEMORY TYPE
ROM
1
0
0
0
0
1
BIT 7
0
0
BIT 0
Hardwired connections to show the device ID.
A2h Table 02h, Register CFh: DEVICE VER
FACTORY DEFAULT
DEVICE VERSION
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
N/A
MEMORY TYPE
ROM
CFh
DEVICE VERSION
BIT 7
BIT 0
Hardwired connections to show the device version.
77
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register D0h–DFh: EMPTY
FACTORY DEFAULT
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
None
These registers do not exist.
A2h Table 02h, Register E0h: RXCTRL1
E0h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
A2h Table 02h, Register E1h: RXCTRL2
E1h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
BIT 7
26
25
24
23
22
21
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
78
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register E2h: SETCML
E2h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
A2h Table 02h, Register E3h: SETLOSH
E3h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. Only written if SETLOSCTL is 1. If SETLOSCTL is 0, then SETLOSL register is used. After either
VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is set high (visible in 3-wire TXSTAT1 bit 7),
or on a rising edge of TXD, this value is written to a Maxim laser driver through the 3-wire interface.
A2h Table 02h, Register E4h: TXCTRL1
E4h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
BIT 7
26
25
24
23
22
21
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
79
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register E5h: TXCTRL2
E5h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
A2h Table 02h, Register E6h: TXCTRL3
E6h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
20
POW_LEV_INIT
BIT 7
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface. For bits 2:1, see the POW_LEV[1:0] bits in A2h Lower Memory, Register 6Fh and
Table 11a and Table 11b.
A2h Table 02h, Register E7h: TXCTRL4
E7h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
BIT 7
26
25
24
23
22
21
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
80
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register E8h: TXCTRL5 APC OL
E8h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface. This register is active only during the open loop and APC loop modes. See Register
CBh for TXCTRL5 access during the dual closed-loop mode.
A2h Table 02h, Register E9h: TXCTRL6
E9h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
A2h Table 02h, Register EAh: TXCTRL7
EAh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
BIT 7
26
25
24
23
22
21
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is
set high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver
through the 3-wire interface.
81
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register EBh: RESERVED
FACTORY DEFAULT
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
This register is reserved.
A2h Table 02h, Register ECh: SETLOSH_3945
ECh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A2h Table 02h, Register EDh: SETLOSL_3945
EDh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
BIT 7
26
25
24
23
22
21
20
BIT 0
A 3-wire slave register. Only written if SETLOSCTL is 0. If SETLOSCTL is 1, then the SETLOSH register is used. After
either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is set high (visible in 3-wire TXSTAT1
bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver through the 3-wire interface.
82
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register EEh: SETLOSTIMER_3945
EEh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. After either VCC exceeds POA (after a POR event), a Maxim laser driver TX_POR bit is set
high (visible in 3-wire TXSTAT1 bit 7), or on a rising edge of TXD, this value is written to a Maxim laser driver through
the 3-wire interface.
A2h Table 02h, Register EFh: 3WSET
EFh
FACTORY DEFAULT
60h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
TEMP_UPD
RSTRT_3710
EN_3945
BIT 7
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
BIT 0
BIT 7
TEMP_UPD:
0 = Default 3-wire operation.
1 = All the control registers (from Register 0Eh–E8h and Register EAh) are written every temperature
conversion.
BIT 6
EN_3945:
0 = Bytes associated with the MAX3945 are not sent on the 3-wire bus.
1 = Bytes associated with the MAX3945 are transmitted on the 3-wire bus on power-up (after VCC
crosses the VCC LO alarm).
BIT 5
RSTRT_3710:
0 = TXINLOS (TXSTAT1 register) does not affect system restart.
1 = When TXINLOS (TXSTAT1 register) is set, Register E9h (TXCTRL6) is written to MAX3710
periodically every tRR.
BITS 4:0
RESERVED
83
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register F0h: 3WCTRL
F0h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Volatile
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
3WMAN_3945
BIT 7
BITS 7:3
3WRW
3WDIS
BIT 0
RESERVED
BIT 2
3WMAN_3945: When this bit is set when 3WRW is set, only the MAX3945 is written using CSELOUT2.
BIT 1
3WRW: Initiates a 3-wire read or write operation. The write command uses the memory address found
in the 3-wire ADDRESS register (A2h Table 02h, Register F1h) and the data from the 3-wire WRITE
register (A2h Table 02h, Register F2h). The read command uses the memory address found in the
3-wire ADDRESS register (A2h Table 02h, Register F1h). The address determines whether a read or
write operation is to be performed. This bit clears itself at the completion of the operation.
0 = (Default) Reads back as 0 when the read or write operation is completed.
1 = Initiates a 3-wire read or write operation.
BIT 0
3WDIS: Disables all automatic communication across the 3-wire interface. This includes all updates
from the LUTs, the APC loop, and status registers updates. The only 3-wire communication is with the
manual mode of operation.
0 = (Default) Automatic communication is enabled.
1 = Disables automatic communication.
A2h Table 02h, Register F1h: ADDRESS
F1h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
BIT 7
26
25
24
23
22
21
20
BIT 0
This byte is used during manual 3-wire communication. When a manual read or write is initiated, this register contains the
address for the operation.
84
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register F2h: WRITE
F2h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
This byte is used during manual 3-wire communication. When a manual write is initiated, this register contains the
address for the operation.
A2h Table 02h, Register F3h: READ
F3h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
N/A
MEMORY TYPE
Volatile
27
26
25
24
23
22
21
BIT 7
20
BIT 0
This byte is used during maunual 3-wire communication. When a manual read is initiated, the return data is stored
in this register.
A2h Table 02h, Register F4h: TXSTAT2
F4h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
27
BIT 7
26
25
24
23
22
21
20
BIT 0
A 3-wire slave register. This value is read from a Maxim laser driver with the 3-wire interface every tRR (see the
Analog Voltage Monitoring Characteristics table).
85
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 02h, Register F5h: TXSTAT1
F5h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. This value is read from a Maxim laser driver with the 3-wire interface every tRR (see the
Analog Voltage Monitoring Characteristics table).
A2h Table 02h, Register F6h: DPCSTAT
F6h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
A 3-wire slave register. This value is read from a Maxim laser driver with the 3-wire interface every tRR (see the
Analog Voltage Monitoring Characteristics table).
A2h Table 02h, Register F7h: RXSTAT
F7h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
27
26
25
BIT 7
24
23
22
21
20
BIT 0
A 3-wire slave register. This value is read from a Maxim laser driver with the 3-wire interface every tRR (see the
Analog Voltage Monitoring Characteristics table).
A2h Table 02h, Register F8h–FFh: RESERVED
FACTORY DEFAULT
00h
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
Nonvolatile (SEE)
These registers are reserved.
86
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 04h Register Descriptions
A2h Table 04h, Register 80h–A7h: MODULATION or TXCTRL5 LUT
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (EE)
Open Loop and APC Loop (Modulation), Dual Closed Loop (TXCTRL5)
80h–A7h
27
26
25
24
23
22
21
20
The digital value for the modulation DAC output or TXCTRL5 register in MAX3710. The MODULATION LUT is a set
of registers assigned to hold the temperature profile for the MODULATION register. The temperature measurement
is used to index the LUT (TINDEX, A2h Table 02h, Register 81h) in 2NC increments from -40NC to +102NC, starting
at 80h. Values recalled from this EEPROM memory table are written into the MODULATION VALUE register (A2h
Table 02h, Register 82h–83h) location, which holds the value until the next temperature conversion. The part can
be placed into a manual mode (MOD LUT EN bit, A2h Table 02h, Register 80h), where MODULATION register is
directly controlled for calibration. If the temperature compensation functionality is not required, then program the
entire table to the desired modulation setting. See the BIAS, MODULATION, SET_2XAPC, TXCTRL5 LUTs section for
more details. The MODULATION VALUE written to the register is determined as follows:
MODULATION VALUE = MODULATION LUT + 4 x MOD OFFSET LUT
A2h Table 04h, Register A8h–EFh: EMPTY
FACTORY DEFAULT
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are empty.
A2h Table 04h, Register F0h–F7h: MOD MAX LUT
F0h–F7h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (EE)
28
BIT 7
27
26
25
24
23
22
21
BIT 0
87
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 04h, Register F8h–FFh: MOD OFFSET or SET_IMOD LUT
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (EE)
Open Loop, APC Loop, and Dual Closed Loop (SET_IMOD)
F8h–FFh
29
28
27
26
25
24
23
BIT 7
22
BIT 0
A2h Table 06h Register Descriptions
A2h Table 06h, Register 80h–A7h: BIAS or SET_IBIAS
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (EE)
Open Loop
80h–A7h
27
26
25
24
23
22
21
20
27
26
25
24
23
22
APC Loop and Dual Closed Loop
80h–A7h
29
BIT 7
28
BIT 0
The BIAS LUT is a set of registers assigned to hold the temperature profile for the BIAS reference DAC. The
temperature measurement is used to index the LUT (TINDEX, A2h Table 02h, Register 81h) in 2NC increments.
Values recalled from this EEPROM memory table are written into the BIAS or SET_IBIAS location, which holds the
value until the next temperature conversion. The part can be placed into a manual mode, where BIAS or SET_IBIAS
can be directly controlled for calibration. If TE temperature compensation is not required by the application,
program the entire LUT to the desired BIAS value.
88
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 06h, Register A8h–EFh: EMPTY
FACTORY DEFAULT
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are empty.
A2h Table 06h, Register F0h–F7h: BIAS MAX LUT
F0h–F7h
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (EE)
29
28
27
26
25
24
23
BIT 7
22
BIT 0
A2h Table 06h, Register F8h–FFh: BIAS OFFSET or APC LUT
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL246) or (PW1 and RBL246)
WRITE ACCESS
PW2 or (PW1 and RWTBL246)
MEMORY TYPE
Nonvolatile (EE)
Open Loop
F8h–FFh
29
28
27
26
25
24
23
22
24
23
22
21
20
APC Loop and Dual Closed Loop (APC)
F8h–FFh
27
BIT 7
26
25
BIT 0
89
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
A2h Table 08h Register Descriptions
A2h Table 08h, Register 80h–F7h: EMPTY
FACTORY DEFAULT
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are empty.
A2h Table 08h, Register F8h–FFh: INCBYTE
F8h–FFh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL78) or (PW1 and RTBL78)
WRITE ACCESS
PW2 or (PW1 and RWTBL78)
MEMORY TYPE
Nonvolatile (EE)
27
26
25
24
23
22
21
BIT 7
20
BIT 0
Bits 7:4 update the upper nibble of the INCBYTE register (Table 02h, Register CAh). Bits 3:0 update the lower
nibble of the INCBYTE register. See the INCBYTE register descriptions for more details.
A2h Table 09h Register Descriptions
A2h Table 09h, Register 80h–F7h: EMPTY
FACTORY DEFAULT
READ ACCESS
N/A
WRITE ACCESS
N/A
MEMORY TYPE
These registers are empty.
A2h Table 09h, Register F8h–FFh: DAC OFFSET LUT
F8h–FFh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWTBL78) or (PW1 and RTBL78)
WRITE ACCESS
PW2 or (PW1 and RWTBL78)
MEMORY TYPE
Nonvolatile (EE)
29
BIT 7
28
27
26
25
24
23
22
BIT 0
90
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Auxiliary Memory A0h Register Description
Auxiliary Memory A0h, Register 00h–FFh: EEPROM
00h–FFh
FACTORY DEFAULT
00h
READ ACCESS
PW2 or (PW1 and RWAUXA) or (PW1 and RWAUXAU)
WRITE ACCESS
PW2 or (PW1 and RWAUXA)
MEMORY TYPE
Nonvolatile (EE)
27
26
25
24
23
22
21
20
BIT 7
BIT 0
Accessible with the slave address A0h.
Applications Information
Power-Supply Decoupling
To achieve best results, it is recommended that the power
supply is decoupled with a 0.01µF or a 0.1µF capacitor.
Use high-quality, ceramic, surface-mount capacitors,
and mount the capacitors as close as possible to the VCC
and GND pins to minimize lead inductance.
Layout Considerations
Connect all GND pins to a common ground plane.
Connect all VCC pins together.
SDA and SCL Pullup Resistors
SDA is an open-collector output on the device that
requires a pullup resistor to realize high-logic levels. A
master using either an open-collector output with a pullup resistor or a push-pull output driver can be used for
SCL. Pullup resistor values should be chosen to ensure
that the rise and fall times listed in the I2C AC Electrical
Characteristics are within specification.
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
DS1886T+
-40NC to +95NC
24 TQFN-EP*
DS1886T+T
-40NC to +95NC
24 TQFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
*EP = Exposed pad.
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
24 TQFN-EP
T2445+1
21-0201
90-0083
91
DS1886
SFP and PON ONU Controller
with Digital LDD Interface
Revision History
REVISION
NUMBER
REVISION
DATE
0
3/12
1
8/12
DESCRIPTION
Initial release
PAGES
CHANGED
—
Made numerous LUT addressing changes for TXINLOS
30, 32, 33, 39,
83, 87, 88, 89
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical
Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated Products, Inc. 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000
© 2012
Maxim Integrated Products 92
Maxim is a registered trademark of Maxim Integrated Products, Inc.