MAXIM MAX3885ECB

19-4767; Rev 2; 1/99
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MANUA
ION KIT HEET
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EVA
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FOLLO
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
Features
The MAX3885 deserializer is ideal for converting
2.488Gbps serial data to 16-bit wide, 155Mbps parallel
data in SDH/SONET applications. Operating from a single +3.3V supply, this device accepts PECL serial
clock and data inputs, and delivers low-voltage differential-signal (LVDS) clock and data outputs for interfacing with high-speed digital circuitry. It also provides an
LVDS synchronization input that enables data realignment and reframing. The MAX3885 is available in the
extended temperature range (-40°C to +85°C) in a 64pin TQFP package.
♦ Single +3.3V Supply
♦ 2.488Gbps Serial to 155Mbps Parallel Conversion
♦ 660mW Operating Power
♦ LVDS Data Outputs and Synchronization Inputs
♦ Self-Biasing PECL Inputs Ease AC Coupling
♦ Synchronization Inputs for Data Realignment and
Reframing
Applications
Ordering Information
2.488Gbps SDH/SONET Transmission Systems
PART
MAX3885ECB
Add/Drop Multiplexers
Digital Cross Connects
TEMP. RANGE
PIN-PACKAGE
-40°C to +85°C
64 TQFP
Pin Configuration appears at end of data sheet.
Typical Operating Circuit
VCC = +3.3V
VCC = +3.3V
VCC
VCC = +3.3V
133Ω
PD15+
133Ω
100Ω*
SD+
PD15-
MAX3875
SD86.6Ω
SERIAL DATA
INPUTS
DATA
AND
CLOCK
RECOVERY
86.6Ω
•
•
•
MAX3885
OVERHEAD
TERMINATION
PD0+
100Ω*
VCC = +3.3V
PD0133Ω
133Ω
PCLK+
100Ω*
SCLK+
PCLK-
SCLK86.6Ω
SYNC+
86.6Ω
SYNCGND
*REQUIRED ONLY IF OVERHEAD CIRCUIT DOES NOT INCLUDE INTERNAL INPUT TERMINATION.
THIS SYMBOL REPRESENTS A TRANSMISSION LINE OF CHARACTERISTIC IMPEDANCE Z0 = 50Ω.
________________________________________________________________ Maxim Integrated Products
1
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MAX3885
General Description
MAX3885
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
ABSOLUTE MAXIMUM RATINGS
Positive Supply Voltage (VCC)...............................-0.5V to +7.0V
Input Voltage Level (all inputs)...................-0.5V to (VCC + 0.5V)
Output Current LVDS outputs .............................................10mA
Continuous Power Dissipation (TA = +85°C)
TQFP (derate 24mW/°C above +85°C) .......................1000mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-60°C to +160°C
Lead Temperature (soldering, 10sec) .............................+300°C
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.
DC ELECTRICAL CHARACTERISTICS
(VCC = +3.0V to +3.6V, differential loads = 100Ω ±1%, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +3.3V,
TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
UNITS
MIN
TYP
MAX
Supply Current
ICC
200
280
mA
PECL INPUTS (SD+/-, SCLK+/-)
Input High Voltage
VIH
VCC - 1.16
VCC - 0.88
V
Input Low Voltage
VIL
VCC - 1.81
VCC - 1.48
V
Input High Current
IIH
VIN = VIH(MAX)
-900
900
µA
Input Low Current
IIL
VIN = VIL(MIN)
-900
900
µA
LVDS INPUTS AND OUTPUTS (SYNC+/-, PCLK+/-, PD_+/-)
Input Voltage Range
VI
Differential Input Threshold
VIDTH
Threshold Hysteresis
VHYST
Differential Input Resistance
RIN
Output High Voltage
VOH
Output Low Voltage
VOL
V
 OD
Differential Output Voltage
Change in Magnitude of Differential
Output Voltage for Complementary
States
Output Offset Voltage
Differential input voltage = 100mV
Common-mode voltage = 50mV
0
2.4
V
-100
100
mV
78
85
100
Figure 1
Single-Ended Output Resistance
RO
Change in Magnitude of SingleEnded Output Resistance for
Complementary Outputs
∆RO
V
V
250
VOS
∆VOS
Ω
1.475
0.925
400
mV
±25
mV
1.275
V
±25
mV
95
140
Ω
±2.5
±10
%
∆ V OD
Change in Magnitude of Output
Offset Voltage for Complementary
States
mV
115
1.125
40
AC ELECTRICAL CHARACTERISTICS
(VCC = +3.0V to +3.6V, differential loads = 100Ω ±1%, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +3.3V,
TA = +25°C.) (Note 1, Figure 4)
PARAMETER
Maximum Serial Clock Frequency
Serial Data Setup Time
Serial Data Hold Time
Parallel Clock-to-Data Output Delay
SYMBOL
CONDITIONS
MIN
TYP
UNITS
2.488
GHz
tSU
100
ps
tH
100
tCLK-Q
200
ps
450
Note 1: AC Characteristics guaranteed by design and characterization.
2
MAX
fSCLK
_______________________________________________________________________________________
900
ps
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
4.2
4.1
4.0
SERIAL DATA-HOLD TIME (ps)
SERIAL DATA-SETUP TIME (ps)
VCC = 3V
0
MAX3885-02
100
MAX3885-01
VCC = 3.6V
4.3
80
60
40
20
0
25
50
75
100
-50
TEMPERATURE (°C)
-25
0
25
50
75
-25
VCC = 3V
150
100
25
50
TEMPERATURE (°C)
75
100
PCLK TO DATA OUTPUT PROPAGATION DELAY (ps)
MAX3885-04
VCC = 3.6V
200
0
25
50
75
100
TEMPERATURE (°C)
PARALLEL CLOCK TO DATA OUTPUT
PROPAGATION DELAY vs. TEMPERATURE
250
0
-80
TEMPERATURE (°C)
300
-25
-60
-50
100
SUPPLY CURRENT vs. TEMPERATURE
-50
-40
700
MAX3885-05
-25
-20
-100
0
-50
SUPPLY CURRENT (mA)
MAX SERIAL CLOCK FREQUENCY (GHz)
4.4
SERIAL DATA-HOLD TIME
vs. TEMPERATURE
SERIAL DATA-SETUP TIME
vs. TEMPERATURE
MAX3885-03
MAXIMUM SERIAL CLOCK FREQUENCY
vs. TEMPERATURE
600
500
400
300
200
-50
-25
0
25
50
75
100
TEMPERATURE (°C)
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MAX3885
Typical Operating Characteristics
(VCC = +3.3V, TA = +25°C, unless otherwise noted.)
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
MAX3885
Pin Description
PIN
NAME
FUNCTION
1, 2, 8, 16, 17,
24, 32, 33, 41,
48, 49, 57, 64
GND
Ground
3, 5, 7, 9, 11,
13, 25, 34, 42,
47, 56
VCC
+3.3V Supply Voltage
4
SD+
Serial Data Noninverting PECL Input. Data is clocked on the SCLK signal’s positive transition.
6
SD-
Serial Data Inverting PECL Input. Data is clocked on the SCLK signal’s positive transition.
10
SCLK+
Serial Clock Noninverting PECL Input
12
SCLK-
Serial Clock Inverting PECL Input
14
SYNC-
Synchronizing Pulse Inverting LVDS Input. Pulse the SYNC signal high for at least four SCLK
periods to shift the data alignment by dropping one bit.
15
SYNC+
Synchronizing Pulse Noninverting LVDS Input. Pulse the SYNC signal high for at least four
SCLK periods to shift the data alignment by dropping one bit.
18
PCLK-
Parallel Clock Inverting LVDS Output
19
PCLK+
Parallel Clock Noninverting LVDS Output
20, 22, 26, 28,
30, 35, 37, 39,
43, 45, 50, 52,
54, 58, 60, 62
PD0- to PD15-
Parallel Data Inverting LVDS Outputs. Data is updated on the negative transition of the PCLK
signal.
21, 23, 27, 29,
31, 36, 38, 40,
44, 46, 51, 53,
55, 59, 61, 63
PD0+ to PD15+
Parallel Data Noninverting LVDS Outputs. Data is updated on the negative transition of the
PCLK signal.
PD+
RL = 100Ω
D
V
VOD
PDVPD-
VOH
|VOD|
SINGLE-ENDED OUTPUT
VPD+
VOS
VOL
+VOD
VPD+ - VPDDIFFERENTIAL OUTPUT
0V (DIFF.)
0V
VOD, P - P = VPD+ - VPD-VOD
Figure 1. Driver Output Levels
4
_______________________________________________________________________________________
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
The MAX3885 deserializer uses a 16-bit shift register,
16-bit parallel output register, 4-bit counter, PECL input
buffers, and low-voltage differential-signal (LVDS)
input/output buffers to convert 2.488Gbps serial data to
16-bit wide, 155Mbps parallel data (Figure 2). The input
PD15+
SD+
PECL
SD-
16-BIT
SHIFT
REGISTER
SCLK+
16-BIT
PARALLEL
OUTPUT
REGISTER
LVDS
PD15-
PECL
SCLK-
PD1+
LVDS
MAX3885
PD1PD0+
LVDS
SYNC+
100Ω LVDS
SYNC-
PD0PCLK+
4-BIT
COUNTER
LVDS
PCLK-
Figure 2. Functional Diagram
D15
D14
shift register continuously clocks incoming data on the
positive transition of the serial clock (SCLK) input signal. The 4-bit counter generates a parallel-output clock
(PCLK) by dividing the serial-clock frequency by 16.
The PCLK signal clocks the parallel-output register.
During normal operation, the counter divides the SCLK
frequency by 16, causing the output register to latch
every 16 bits of incoming serial data. The synchronization inputs (SYNC+, SYNC-) realign and reframe data.
When the SYNC signal is pulsed high for at least four
SCLK cycles, the parallel output data is delayed by one
SCLK cycle. This realignment is guaranteed to occur
within two complete PCLK cycles of the SYNC signal’s
positive transition. As a result, the first incoming bit of
data during that PCLK cycle is dropped, shifting the
alignment between PCLK and data by one bit. See
Figure 3 for the timing diagram and Figure 4 for the timing parameters diagram.
Low-Voltage Differential-Signal (LVDS)
Inputs and Outputs
The MAX3885 features LVDS inputs and outputs for
interfacing with high-speed digital circuitry. The LVDS
standard is based on the IEEE 1596.3 LVDS specification. This technology uses 500mVp-p to 800mVp-p differential low-voltage swings to achieve fast transition
times, minimize power dissipation, and improve noise
immunity. The parallel clock and data LVDS outputs
(PCLK+, PCLK-, PD_+, PD_-) require 100Ω differential
D13
SCLK
SD
SYNC
PCLK
(LSB) PD0
D0
D16
D32
D48
D65
PD1
D1
D17
D33
D49
D66
•
•
•
(MSB) PD15
TRANSMITTED FIRST
ONE BIT HAS SLIPPED
IN THIS TIME SLICE
D15
D31
D47
D64
D80
Figure 3. Timing Diagram
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5
MAX3885
Detailed Description
MAX3885
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
tSCLK = 1 / fSCLK
SCLK
tSU
tH
SD
PCLK
tCLK-Q
PD0–PD15
NOTE: SIGNALS SHOWN ARE DIFFERENTIAL. FOR EXAMPLE, SCLK = (SCLK+) - (SCLK-).
Figure 4. Timing Parameters
DC termination between the inverting and noninverting
outputs for proper operation. Do not terminate these
outputs to ground. The synchronization LVDS inputs
(SYNC+, SYNC-) are internally terminated with 100Ω
differential input resistance and, therefore, do not
require external termination.
THEVENIN-EQUIVALENT TERMINATION
+3.3V
133Ω
133Ω
MAX3885
ZO = 50Ω
PECL Inputs
Because of the self-biasing resistor networks, the serial
data and clock PECL inputs (SD+, SD-, SCLK+, SCLK-)
require 53Ω termination to VCC - 2V when interfacing
with a PECL source (see Alternative PECL Input
Termination). This results in an equivalent input resistance of 50Ω.
PECL
INPUTS
ZO = 50Ω
86.6Ω
86.6Ω
Applications Information
Alternative PECL Input Termination
Figure 5 shows alternative PECL input-termination
methods. Use Thevenin-equivalent termination when a
VCC - 2V termination voltage is not available. When
interfacing with an ECL-output device, the MAX3885’s
internal self-biasing allows easy ECL AC-coupling termination.
ECL AC-COUPLING TERMINATION
ZO = 50Ω
53Ω
Layout Techniques
For best performance, use good high-frequency layout
techniques. Filter voltage supplies and keep ground
connections short. Use multiple vias where possible.
Also, use controlled impedance transmission lines to
interface with the MAX3885 high-speed inputs and outputs.
MAX3885
ZO = 50Ω
PECL
INPUTS
-2V
53Ω
-2V
Figure 5. Alternative PECL Input Termination
6
_______________________________________________________________________________________
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
47 46 45 44 43 42 41 40 39 38 37 36 35 34 33
VCC
GND
PD5-
PD6-
PD5+
PD6+
PD7-
PD7+
48
VCC
GND
PD8-
PD8+
PD9-
VCC
PD9+
GND
TOP VIEW
GND 49
32 GND
PD10- 50
31 PD4+
PD10+ 51
30 PD4-
PD11- 52
29 PD3+
PD11+ 53
28 PD3-
PD12- 54
27 PD2+
PD12+ 55
26 PD225 VCC
VCC 56
MAX3885
GND 57
24 GND
PD13- 58
23 PD1+
PD13+ 59
22 PD1-
PD14- 60
21 PD0+
PD14+ 61
20 PD0-
PD15- 62
19 PCLK+
PD15+ 63
18 PCLK-
GND 64
8
9
GND
VCC
SD+
VCC
SD-
VCC
GND
VCC
10 11 12 13 14 15 16
GND
7
SYNC-
6
SYNC+
5
VCC
4
SCLK-
3
VCC
2
SCLK+
1
GND
17 GND
TQFP
___________________Chip Information
TRANSISTOR COUNT: 2820
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MAX3885
Pin Configuration
+3.3V, 2.488Gbps, SDH/SONET
1:16 Deserializer with LVDS Outputs
TQFPPO.EPS
MAX3885
Package Information
8
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