Datasheet

Dual 14-Bit, 250/200/125 MSPS JESD204B High Speed
Serial Output ADC
ISLA224S
Features
The ISLA224S is a series of low-power, high-performance,
dual-channel 14-bit, analog-to-digital converters. Designed
with FemtoCharge™ technology on a standard CMOS process,
the series supports sampling rates of up to 250MSPS. The
ISLA224S is part of a pin-compatible family of 12- and 14-bit
dual-channel A/Ds with maximum sample rates ranging from
125MSPS to 250MSPS and shares the same analog core as
Intersil's proven ISLA224P series of ADCs. The family
minimizes power consumption while providing state-of-the art
dynamic performance, offering an optimal performance-vspower trade-off.
• JESD204A/B High Speed Data Interface
Differentiating the ISLA224S from the ISLA224P is its highly
configurable, JESD204B-compliant, high speed serial output
link. The link offers data rates up to 4.375Gbps per lane and
multiple packing modes. It can be configured to use two or
three lanes to transmit the conversion data, allowing for
flexibility in the receiver design. The SERDES transmitter also
provides deterministic latency and multi-chip time alignment
support to satisfy an application's complex synchronization
requirements.
A serial peripheral interface (SPI) port allows for extensive
configurability of the JESD204B transmitter including access
to its built-in link and transport-layer test patterns. The SPI port
also provides control for numerous additional features
including the fine gain and offset adjustments of the two ADC
cores as well as the programmable clock divider, enabling 2x
and 4x harmonic clocking.
The ISLA224S is available in a space-saving 7mmx7mm 48 Ld
QFN package. The package features a thermal pad for
improved thermal performance and is specified over the full
industrial temperature range (-40°C to +85°C).
- JESD204A Compliant
- JESD204B Device Subclass 0 Compliant
- JESD204B Device Subclass 2 Compatible
- Up to 3 JESD204 Output Lanes Running up to 4.375Gbps
- Highly Configurable JESD204 Transmitter
• Multiple Chip Time Alignment and Deterministic Latency
Support (JESD204B Device Subclass 2)
• SPI Programmable Debugging Features and Test Patterns
• 48-pin QFN 7mmx7mm Package
Key Specifications
• SNR @ 250/200/125MSPS
73.2/74.1/75.1 dBFS fIN = 30MHz
72.4/72.9/73.2 dBFS fIN = 190MHz
• SFDR @ 250/200/125MSPS
82/91/94 dBc fIN = 30MHz
84/82/81 dBc fIN = 190MHz
• Total Power Consumption: 989mW @ 250MSPS
Applications
• Radar and Satellite Antenna Array Processing
• Broadband Communications and Microwave Receivers
• High-Performance Data Acquisition
• Communications Test Equipment
• High-Speed Medical Imaging
Pin-Compatible Family
RESOLUTION
SPEED
(MSPS)
PRODUCT
AVAILABILITY
ISLA224S25
14
250
Now
ISLA224S20
14
200
Now
MODEL
ISLA224S12
14
125
Now
ISLA222S25
12
250
Now
ISLA222S20
12
200
Now
ISLA222S12
12
125
Now
FIGURE 1. SERDES DATA EYE AT 4.375Gbps
April 25, 2013
FN7911.2
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2011-2013. All Rights Reserved
Intersil (and design) and FemtoCharge are trademarks owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
CLKP
OVDD
OVDD
(PLL)
SYNC
AVDD
ISLA224S
CLOCK
GENERATION
CLKN
AINP
14-BIT
250MSPS
ADC
SHA
AINN
LANE[2:0]P
LANE[2:0]N
VREF
JESD204
TRANSMITTER
VCM
BINP
14-BIT
250MSPS
ADC
SHA
BINN
VREF
+
–
OVSS
CSB
SCLK
SDIO
SDO
SPI
CONTROL
RESETN
AVSS
(PLL)
NAPSLP
AVSS
1.25V
FIGURE 2. BLOCK DIAGRAM
Pin Configuration
DNC
DNC
AVDD
NAPSLP
CLKDIV
SDIO
SCLK
CSB
SDO
OVDD
OVSS
OVSS
ISLA224S
(48 LD QFN)
TOP VIEW
48
47
46
45
44
43
42
41
40
39
38
37
VCM
1
36 OVDD
AVDD
2
35 OVSS
AVSS
3
34 LANE2N
BINP
4
33 LANE2P
BINN
5
32 OVSS
AVSS
6
31 LANE1N
AVSS
7
30 LANE1P
AINN
8
29 OVSS
AINP
9
28 LANE0N
AVSS
10
27 LANE0P
AVDD
11
DNC
12
2
26 OVSS
PAD – Exposed Paddle
13
14
15
16
17
18
19
20
21
22
23
24
RESETN
AVDD
AVDD
CLKP
CLKN
SYNCP
SYNCN
DNC
OVSS (PLL)
OVDD (PLL)
OVSS (PLL)
OVDD (PLL)
25 OVDD
FN7911.2
April 25, 2013
ISLA224S
Pin Descriptions
PIN NUMBER
NAME
FUNCTION
2, 11, 14, 15, 46
AVDD
1.8V Analog Supply
12, 20, 47, 48
DNC
Do Not Connect
3, 6, 7, 10
AVSS
Analog Ground
4, 5
BINP, BINN
B-Channel Analog Input Positive, Negative
8, 9
AINN, AINP
A-Channel Analog Input Negative, Positive
1
VCM
44
CLKDIV
16, 17
CLKP, CLKN
45
NAPSLP
Power Control (Nap, Sleep modes)
13
RESETN
Power On Reset (Active Low)
26, 29, 32, 35, 37, 38
OVSS
Output Ground
25, 36, 39
OVDD
1.8V Digital Supply
Common Mode Output
Clock Divider Control
Clock Input True, Complement
22, 24
OVDD (PLL)
1.8V Analog Supply for SERDES PLL
21, 23
OVSS (PLL)
Analog Ground Supply for SERDES PLL
18, 19
SYNCP, SYNCN
27, 28
LANE0P, LANE0N
SERDES Lane 0
30, 31
LANE1P, LANE1N
SERDES Lane 1
33, 34
LANE2P, LANE2N
SERDES Lane 2
40
SDO
SPI Serial Data Output
41
CSB
SPI Chip Select (active low)
42
SCLK
SPI Clock
43
SDIO
SPI Serial Data Input/Output
PAD
AVSS
Exposed Paddle. Analog Ground (connect to AVSS)
JESD204 SYNC Input
Ordering Information
PART NUMBER
(Notes 1, 2)
PART
MARKING
TEMP. RANGE
(°C)
PACKAGE
(Pb-free)
PKG.
DWG. #
ISLA224S25IR1Z
ISLA224S25 IR1Z
-40 to +85
48 Ld QFN
L48.7x7G
ISLA224S20IR1Z
ISLA224S20 IR1Z
-40 to +85
48 Ld QFN
L48.7x7G
ISLA224S12IR1Z
ISLA224S12 IR1Z
-40 to +85
48 Ld QFN
L48.7x7G
Coming Soon
ISLA224S25IR48EV1Z
FMC Based Evaluation Board (Supports 125/200/250 speed grades), Interfaces with ADCMB-HSFMC-EV1Z
Motherboard and Other FPGA Vendor FMC Based Evaluation Platforms
Coming Soon
ADCMB-HSFMC-EV1Z
FMC Based Motherboard
NOTES:
1. These Intersil Pb-free plastic packaged products employ special Pb-free material sets; molding compounds/die attach materials and NiPdAu plate-e4
termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL
classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
2. For Moisture Sensitivity Level (MSL), please see device information page for ISLA224S12, ISLA224S20, ISLA224S25. For more information on MSL
please see techbrief TB363.
3
FN7911.2
April 25, 2013
ISLA224S
Table of Contents
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Thermal Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Digital Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Switching Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Typical Performance Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Theory of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power-On Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
User Initiated Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15
15
15
16
Temperature Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Analog Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clock Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Digital Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nap/Sleep. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17
18
18
19
19
19
19
19
20
Clock Divider Synchronous Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Soft Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
JESD204 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Initial Lane Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Test Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Serial Peripheral Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPI Physical Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPI Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Device Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Device Configuration/Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Global Device Configuration/Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ADDRESS 0xDF - 0xF3: JESD204 REGISTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Address 0xDF-0xEE: JESD204 Parameter INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25
25
26
26
26
27
29
29
SPI Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Equivalent Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
ADC Evaluation Platform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Layout Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Split Ground and Power Planes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clock Input Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exposed Paddle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bypass and Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CML Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unused Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
36
36
36
36
36
36
36
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
About Intersil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Package Outline Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4
FN7911.2
April 25, 2013
ISLA224S
Absolute Maximum Ratings
Thermal Information
AVDD to AVSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.4V to 2.1V
OVDD to OVSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.4V to 2.1V
AVSS to OVSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 0.3V
Analog Inputs to AVSS . . . . . . . . . . . . . . . . . . . . . . . . . -0.4V to AVDD + 0.3V
Clock Inputs to AVSS . . . . . . . . . . . . . . . . . . . . . . . . . . -0.4V to AVDD + 0.3V
Logic Input to AVSS . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.4V to OVDD + 0.3V
Logic Inputs to OVSS . . . . . . . . . . . . . . . . . . . . . . . . . . -0.4V to OVDD + 0.3V
Latchup (Tested per JESD-78C;Class 2,Level A) . . . . . . . . . . . . . . . . 100mA
Thermal Resistance (Typical)
θJA (°C/W) θJC (°C/W)
48 Ld QFN (Notes 3, 4, 5) . . . . . . . . . . . . . .
24
0.4
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .+150°C
Pb-Free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see link below
http://www.intersil.com/pbfree/Pb-FreeReflow.asp
Recommended Operating Conditions
Operating Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C
NOTES:
3. θJA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See Tech
Brief TB379.
4. For θJC, the “case temp” location is the center of the exposed metal pad on the package underside.
5. For solder stencil layout and reflow guidelines, please see Tech Brief TB389.
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product
reliability and result in failures not covered by warranty.
Electrical Specifications All specifications apply under the following conditions unless otherwise noted: AVDD = 1.8V, OVDD = 1.8V,
TA = -40°C to +85°C (typical specifications at +25°C), AIN = -2dBFS, fSAMPLE = Maximum Conversion Rate (per speed grade). Boldface limits apply
over the operating temperature range, -40°C to +85°C.
ISLA224S25
PARAMETER
SYMBOL
CONDITIONS
MIN
(Note 6)
TYP
1.95
2.00
ISLA224S20
ISLA224S12
MAX
MIN
MAX
MIN
MAX
(Note 6) (Note 6) TYP (Note 6) (Note 6) TYP (Note 6)
UNITS
DC SPECIFICATIONS
Analog Input
Full-Scale Analog Input
Range
VFS
Differential
2.15
1.95
2.0
2.15
1.9
2.0
2.1
VP-P
Input Resistance
RIN
Differential
600
600
600
Ω
Input Capacitance
CIN
Differential
7.4
7.4
7.4
pF
Full Temp
115
58
58
ppm/°C
Full Scale Range Temp.
Drift
AVTC
Input Offset Voltage
VOS
Gain Error
EG
1
1
1
%
Common-Mode Output
Voltage
VCM
0.94
0.94
0.94
V
Common Mode Input
Current (per pin)
ICM
6.0
6.0
6.0
µA/MSPS
Inputs Common Mode
Voltage
0.9
0.9
0.9
V
CLKP, CLKN Swing
1.8
1.8
1.8
V
-5.0
±1
5.0
-5.0
±1
5.0
-5.0
±1
5.0
mV
Clock Inputs
Power Requirements
1.8V Analog Supply
Voltage
AVDD
1.7
1.8
1.9
1.7
1.8
1.9
1.7
1.8
1.9
V
1.8V Digital Supply
Voltage
OVDD
1.7
1.8
1.9
1.7
1.8
1.9
1.7
1.8
1.9
V
1.8V Analog Supply
Current
IAVDD
353
375
324
344
282
316
mA
1.8V Digital Supply
Current
IOVDD
195
213
179
196
123
173
mA
Minimum number of
lanes active
5
FN7911.2
April 25, 2013
ISLA224S
Electrical Specifications All specifications apply under the following conditions unless otherwise noted: AVDD = 1.8V, OVDD = 1.8V,
TA = -40°C to +85°C (typical specifications at +25°C), AIN = -2dBFS, fSAMPLE = Maximum Conversion Rate (per speed grade). Boldface limits apply
over the operating temperature range, -40°C to +85°C. (Continued)
ISLA224S25
PARAMETER
SYMBOL
Power Supply Rejection
Ratio (Note 7)
PSRR
CONDITIONS
MIN
(Note 6)
TYP
ISLA224S20
ISLA224S12
MAX
MIN
MAX
MIN
MAX
(Note 6) (Note 6) TYP (Note 6) (Note 6) TYP (Note 6)
UNITS
30MHz 200mVp-p
40
40
40
dB
1MHz 200mVp-p
47
47
47
dB
Total Power Dissipation
Normal Mode
PD
989
1058
910
972
731
843
mW
Nap Mode
PD
447
490
391
453
290
398
mW
Sleep Mode
PD
CSB at logic high
5
12
5
12
6
12
mW
Nap Mode Wakeup
Time
Sample Clock
Running
5
5
5
µs
Sleep Mode Wakeup
Time
Sample Clock
Running
1
1
1
ms
±0.18
LSB
±2.0
LSB
50
MSPS
AC SPECIFICATIONS (Note 8)
Differential Nonlinearity
DNL
Integral Nonlinearity
INL
Minimum Conversion
Rate (Note 9)
fS MIN
fIN=105MHz
No Missing Codes
-1.0
±0.4
1.5
-0.5
±3.0
±0.2
-1.0
±2.0
100
ISLA224S25/20
(3 Lanes, Efficient
Packing)
1
100
ISLA224S12 (2 Lanes,
Simple Packing)
Maximum Conversion
Rate (Note 9)
fS MAX
Efficient Packing
250
Simple Packing
200
125
MSPS
155
125
MSPS
Minimum Serdes Lane
Data Rate
Independent of Packing
Mode
1.0
1.0
1.0
GBPS
Maximum Serdes Lane
Data Rate
Independent of Packing
Mode
4.375
4.375
4.375
GBPS
fIN = 30MHz
73.1
73.8
75.1
dBFS
74.4
dBFS
(See “Lane data rate” on
page 22.)
Signal-to-Noise Ratio
(Note 10)
Signal-to-Noise and
Distortion (Note 10)
SNR
fIN = 105MHz
SINAD
72.9
72.5
73.6
73.0
fIN = 190MHz
72.4
72.9
73.2
dBFS
fIN = 363MHz
71.1
71.1
70.6
dBFS
fIN = 495MHz
70.0
69.5
68.8
dBFS
fIN = 605MHz
69.0
68.3
67.3
dBFS
fIN = 30MHz
72.9
73.7
74.8
dBFS
74.1
dBFS
fIN = 105MHz
6
70.8
68.8
72.5
72.0
73.4
72.7
fIN = 190MHz
72.1
72.1
72.4
dBFS
fIN = 363MHz
70.1
70.3
67.5
dBFS
fIN = 495MHz
66.5
65.8
62.8
dBFS
fIN = 605MHz
58.8
58.5
54.7
dBFS
FN7911.2
April 25, 2013
ISLA224S
Electrical Specifications All specifications apply under the following conditions unless otherwise noted: AVDD = 1.8V, OVDD = 1.8V,
TA = -40°C to +85°C (typical specifications at +25°C), AIN = -2dBFS, fSAMPLE = Maximum Conversion Rate (per speed grade). Boldface limits apply
over the operating temperature range, -40°C to +85°C. (Continued)
ISLA224S25
PARAMETER
SYMBOL
Effective Number of Bits
(Note 10)
ENOB
Spurious-Free Dynamic
Range (Note 10)
Spurious-Free Dynamic
Range Excluding H2, H3
(Note 10)
Intermodulation
Distortion
CONDITIONS
MIN
(Note 6)
fIN = 30MHz
fIN = 105MHz
SFDR
11.8
11.9
11.67
11.9
11.78
UNITS
12.1
Bits
12.0
Bits
11.7
11.7
11.7
Bits
fIN = 363MHz
11.4
11.4
10.9
Bits
fIN = 495MHz
10.8
10.6
10.1
Bits
fIN = 605MHz
9.5
9.4
8.8
Bits
fIN = 30MHz
86
89
94
dBc
86
dBc
74
85
76
88
76
fIN = 190MHz
84
82
81
dBc
fIN = 363MHz
78
79
69
dBc
fIN = 495MHz
68
67
62
dBc
fIN = 605MHz
58
57
53
dBc
87
90
96
dBc
fIN = 105MHz
89
92
94
dBc
fIN = 190MHz
89
91
92
dBc
fIN = 363MHz
86
88
87
dBc
fIN = 495MHz
86
84
84
dBc
fIN = 605MHz
85
83
82
dBc
fIN = 70MHz
83
83
83
dBFS
fIN = 170MHz
97
95
95
dBFS
fIN = 10MHz
88
90
100
dB
fIN = 124MHz
82
87
86
dB
10-13
10-13
675
675
SFDRX23 fIN = 30MHz
Channel-to-Channel
Isolation
MAX
MIN
MAX
MIN
MAX
(Note 6) (Note 6) TYP (Note 6) (Note 6) TYP (Note 6)
11.8
11.14
ISLA224S12
fIN = 190MHz
fIN = 105MHz
IMD
TYP
ISLA224S20
Word Error Rate
WER
10-13
Full Power Bandwidth
FPBW
675
MHz
NOTES:
6. Compliance to datasheet limits is assured by one or more methods: production test, characterization and/or design.
7. PSRR is calculated by the equation 20*log10(A/B), where B is the amplitude of a disturber sinusoid on AVDD at the device pins, and A is the amplitude
of the spur in the captured data at the frequency of the disturber sinusoid.
8. AC Specifications apply after internal calibration of the ADC is invoked at the given sample rate and temperature. Refer to “Power-On Calibration” on
page 15 and “User Initiated Reset” on page 16 for more detail.
9. The DLL Range setting must be changed via SPI for ADC core sample rates below 80MSPS. The JESD204 transmitter can support ADC sample rates
below 100MSPS, as long as the SERDES lane data rate is greater than or equal to 1Gbps.
10. Minimum specification guaranteed when calibrated at +85°C.
7
FN7911.2
April 25, 2013
ISLA224S
Digital Specifications
Boldface limits apply over the operating temperature range, -40°C to +85°C.
PARAMETER
SYMBOL
CONDITIONS
MIN
(Note 6)
TYP
MAX
(Note 6) UNITS
CMOS INPUTS
Input Current High (RESETN)
IIH
VIN = 1.8V
1
10
µA
Input Current Low (RESETN)
IIL
VIN = 0V
-12
-7
µA
Input Current High (SDIO, SCL, SDA SCLK)
IIH
VIN = 1.8V
4
12
µA
Input Current Low (SDIO, SCL, SDA SCLK)
IIL
VIN = 0V
-600
-400
-300
µA
Input Current High (CSB)
IIH
VIN = 1.8V
40
52
70
µA
Input Current Low (CSB)
IIL
VIN = 0V
1
10
µA
Input Voltage High (SDIO, RESETN)
VIH
Input Voltage Low (SDIO, RESETN)
VIL
Input Current High (NAPSLP, CLKDIV) (Note 11)
IIH
19
Input Current Low (NAPSLP, CLKDIV)
IIL
--30
Input Capacitance
CDI
-25
1.17
V
0.63
V
25
30
µA
-25
-19
µA
4
pF
LVDS INPUTS (SYNCP, SYNCN)
Input Common Mode Range
VICM
825
1575
mV
Input Differential Swing (peak-to-peak, single-ended)
VID
250
450
mV
Input Pull-up and Pull-down Resistance
RIpu
100
kΩ
1.14
V
CML OUTPUTS
Output Common Mode Voltage
Switching Specifications
Boldface limits apply over the operating temperature range, -40°C to +85°C.
PARAMETER
SYMBOL
CONDITION
MIN
(Note 6)
TYP
MAX
(Note 6)
UNITS
ADC OUTPUT
Aperture Delay
tA
190
ps
RMS Aperture Jitter
jA
100
fs
250
µs
L
10
cycles
tOVR
1
cycles
PLL Lock Time
250
µs
PLL Bandwidth
2.2
MHz
Added Random Jitter
5
ps
RMS
Added Deterministic Jitter
7
ps P-P
5
ps rms
Synchronous Clock Divider Reset Recovery Time (Note 12)
Latency (ADC Pipeline Delay)
Overvoltage Recovery
tRSTRT
DLL recovery
time after
Synchronous
Reset
SERDES
Maximum Input Sample Clock Total Jitter to Maintain SERDES
BER <1E-12
8
Integrated from
1kHz to 10MHz
offset from
carrier
FN7911.2
April 25, 2013
ISLA224S
Switching Specifications
Boldface limits apply over the operating temperature range, -40°C to +85°C. (Continued)
PARAMETER
SYMBOL
CONDITION
SYNCP, SYNCN Setup Time (with Respect to the Positive Edge of
CLKP)
tRSTS
AVDD,
OVDD = 1.7V to
1.9V, TA = -40°C
to +85°C
SYNCP, SYNCN Hold Time (with respect to the positive edge of
CLKP)
tRSTH
AVDD,
OVDD = 1.7V to
1.9V, TA = -40°C
to +85°C
MIN
(Note 6)
TYP
400
75
MAX
(Note 6)
UNITS
LVDS Inputs
150
ps
350
ps
CML Outputs
Output Rise Time
tR
165
ps
Output Fall Time
tF
145
ps
Data Output Duty Cycle
50
%
Differential Output Resistance
100
Ω
Differential Output Voltage (Note 13)
760
mVP-P
SPI INTERFACE (Notes 14, 15)
SCLK Period
t
CLK
Write Operation
7
cycles
tCLK
Read Operation
16
cycles
CSB↓ to SCLK↑ Setup Time
tS
Read or Write
2
cycles
CSB↑ after SCLK↑ Hold Time
tH
Read or Write
5
cycles
Data Valid to SCLK↑ Setup Time
tDS
Read or Write
6
cycles
Data Valid after SCLK↑ Hold Time
tDH
Read or Write
4
cycles
Data Valid after SCLK↓ Time
tDVR
Read
4
cycles
NOTES:
11. The Tri-Level Inputs internal switching thresholds are approximately. 0.43V and 1.34V. It is advised to float the inputs, tie to ground or AVDD depending
on desired function.
12. The synchronous clock divider reset function is available as a (SPI-programmable) overload on the SYNC input.
13. The voltage is expressed in peak-to-peak differential swing. The peak-to-peak single-ended swing is 1/2 of the differential swing.
14. The SPI interface timing is directly proportional to the ADC sample period (tS). Values above reflect multiples of a 4ns sample period, and must be
scaled proportionally for lower sample rates. ADC sample clock must be running for SPI communication.
15. The SPI may operate asynchronously with respect to the ADC sample clock.
9
FN7911.2
April 25, 2013
ISLA224S
Typical Performance Curves
All Typical Performance Characteristics apply under the following conditions unless otherwise noted: AVDD = OVDD = 1.8V, TA = +25°C, AIN = -2dBFS,
fIN = 105MHz, fSAMPLE = 250MSPS.
95
-50
SFDR AT 200 MSPS
SFDR AT 250 MSPS
85
SFDR AT 125 MSPS
80
75
70
SNR AT 250 MSPS
65
SNR AT 125 MSPS
60
SNR AT 200 MSPS
55
50
0
100
200
300
400
500
600
HD2 AT 125 MSPS
-60
-65
-70
HD2 AT 250 MSPS
-75
-80
-85
-90
HD3 AT 200 MSPS
-95
-100
700
HD2 AT 200 MSPS
-55
HD2 AND HD3 MAGNITUDE (dBc)
SNR (dBFS) AND SFDR (dBc)
90
0
100
200
300
400
500
INPUT FREQUENCY (MHz)
INPUT FREQUENCY (MHz)
FIGURE 3. SNR AND SFDR vs fIN
700
0
SFDR (dBFS)
HD2 AND HD3 MAGNITUDE (dBc)
90
SNR (dBFS)
70
SNR AND SFDR
600
FIGURE 4. HD2 AND HD3 vs fIN
100
80
HD3 AT 250 MSPS
HD3 AT 125 MSPS
60 SFDR (dBc)
50
40
30
20
SNR (dBc)
10
-20
HD3 (dBc)
-40
HD2 (dBc)
-60
-80
HD3 (dBFS)
-100
HD2 (dBFS)
0
-60
-50
-40
-30
-20
-10
-120
-60
0
-50
INPUT AMPLITUDE (dBFS)
FIGURE 5. SNR AND SFDR vs AIN (250MSPS)
0
-75
HD2 AND HD3 MAGNITUDE (dBc)
SNR (dBFS) AND SFDR (dBc)
-10
FIGURE 6. HD2 AND HD3 vs AIN (250MSPS)
90
85
SFDR
80
75
SNR
70
65
60
50
-40
-30
-20
INPUT AMPLITUDE (dBFS)
100
150
200
250
SAMPLE RATE (MSPS)
FIGURE 7. SNR AND SFDR vs fSAMPLE
10
300
HD2
-80
-85
HD3
-90
-95
-100
50
100
150
200
250
300
SAMPLE RATE (MSPS)
FIGURE 8. HD2 AND HD3 vs fSAMPLE
FN7911.2
April 25, 2013
ISLA224S
Typical Performance Curves
All Typical Performance Characteristics apply under the following conditions unless otherwise noted: AVDD = OVDD = 1.8V, TA = +25°C, AIN = -2dBFS,
fIN = 105MHz, fSAMPLE = 250MSPS. (Continued)
1200
1.0
0.8
3 LANES
TOTAL POWER (mW)
1000
0.6
0.4
600
DNL (LSBs)
800
2 LANES
400
0.2
0
-0.2
-0.4
EFFICIENT PACKING
-0.6
200
-0.8
0
50
100
150
200
SAMPLE RATE (MSPS)
250
-1.0
300
10000
15000
FIGURE 10. DIFFERENTIAL NONLINEARITY (250MSPS)
90
4
SNR (dBFS) AND SFDR (dBc)
3
2
INL (LSBs)
5000
CODE
FIGURE 9. POWER vs fSAMPLE
1
0
-1
-2
-3
-4
0
0
5000
10000
85
SFDR
80
75
SNR
70
65
60
700
15000
800
900
1000
CODE
1100
1200
1300
1400
1500
Vcm (mV)
FIGURE 11. INTEGRAL NONLINEARITY (250MSPS)
FIGURE 12. SNR AND SFDR vs VCM (250MSPS)
1.0
4
0.8
3
0.6
2
INL (LSBs)
DNL (LSBs)
0.4
0.2
0
-0.2
1
0
-1
-0.4
-2
-0.6
-3
-0.8
-1.0
0
5000
10000
15000
CODE
FIGURE 13. DIFFERENTIAL NONLINEARITY (125MSPS)
11
-4
0
5000
10000
15000
CODE
FIGURE 14. INTEGRAL NONLINEARITY (125MSPS)
FN7911.2
April 25, 2013
ISLA224S
Typical Performance Curves
All Typical Performance Characteristics apply under the following conditions unless otherwise noted: AVDD = OVDD = 1.8V, TA = +25°C, AIN = -2dBFS,
fIN = 105MHz, fSAMPLE = 250MSPS. (Continued)
0
14000
AIN = -2.0 dBFS
SNR = 72.8 dBFS
SFDR = 83 dBc
SINAD = 72.2 dBFS
STDEV = 1.07 CODES
12000
AMPLITUDE (dBFS)
10000
NUMBER OF HITS
-20
11181
9571
8000
6000
4650
4000
-60
-80
2765
-100
2000
0
0
-40
1
43
1118
514
146 11
0
-120
8199 8200 8201 8202 8203 8204 8205 8206 8207 8208 8209 8210
0
20
ADC CODE
80
100
120
FIGURE 16. SINGLE-TONE SPECTRUM @ 105MHz (250MSPS)
0
0
AIN = -2.0 dBFS
SNR = 71.9 dBFS
-20 SFDR = 80 dBc
SINAD = 71.1 dBFS
AIN = -2.0 dBFS
SNR = 70.5 dBFS
SFDR = 74 dBc
SINAD = 68.8 dBFS
-20
AMPLITUDE (dBFS)
AMPLITUDE (dBFS)
60
FREQUENCY (MHz)
FIGURE 15. NOISE HISTOGRAM (250MSPS)
-40
-60
-80
-100
-120
40
-40
-60
-80
-100
0
20
40
60
80
100
-120
120
0
20
FREQUENCY (MHz)
40
60
80
100
120
FREQUENCY (MHz)
FIGURE 17. SINGLE-TONE SPECTRUM @ 190MHz (250MSPS)
FIGURE 18. SINGLE-TONE SPECTRUM @ 363MHz (250MSPS)
15000
13176
0
STD EV = 0.95
AIN = -2.0 dBFS
SNR = 74.8 dBFS
SFDR = 87.1 dBc
SINAD = 74.7 dBFS
AMPLITUDE (dBFS)
8451
8157
94
8192
1360
74
-60
-80
0
0
-100
8200
2
8191
1454
0
-40
8199
5000
8190
-120
8198
8197
8196
8195
8194
0
8193
NUMBER OF HITS
-20
10000
CODE
FIGURE 19. NOISE SPECTRUM (125MSPS)
12
0
10
20
30
40
FREQUENCY (MHz)
50
60
FIGURE 20. SINGLE-TONE SPECTRUM AT 105MHz (125MSPS)
FN7911.2
April 25, 2013
ISLA224S
Typical Performance Curves
All Typical Performance Characteristics apply under the following conditions unless otherwise noted: AVDD = OVDD = 1.8V, TA = +25°C, AIN = -2dBFS,
fIN = 105MHz, fSAMPLE = 250MSPS. (Continued)
0
0
AIN = -2.0 dBFS
SNR = 73.7 dBFS
SFDR = 86.8 dBc
SINAD = 73.4 dBFS
AIN = -2.0 dBFS
SNR = 70.8 dBFS
SFDR = 71.2 dBc
SINAD = 68.8 dBFS
-20
AMPLITUDE (dBFS)
AMPLITUDE (dBFS)
-20
-40
-60
-80
-100
-40
-60
-80
-100
-120
0
10
20
30
40
50
-120
60
0
10
FREQUENCY (MHz)
40
50
60
FIGURE 22. SINGLE-TONE AT 363MHz (125MSPS)
0
0
IMD = -92 dBFS
IMD = -82 dBFS
-20
MAGNITUDE (dBFS)
-20
MAGNITUDE (dBFS)
30
FREQUENCY (MHz)
FIGURE 21. SINGLE-TONE SPECTRUM AT 190MHz (125MSPS)
-40
-60
-80
-40
-60
-80
-100
-100
-120
0
20
-120
50
FREQUENCY (MHz)
100
FIGURE 23. TWO-TONE SPECTRUM (F1 = 70MHz, F2 = 71MHz AT
-7dBFS) (250MSPS)
FIGURE 25. SERDES DATA EYE at 1.0Gbps
13
0
50
FREQUENCY (MHz)
100
FIGURE 24. TWO-TONE SPECTRUM (F1 = 170MHz, F2 = 171MHz AT 7dBFS) (250MSPS)
FIGURE 26. SERDES DATA EYE at 3.0Gbps
FN7911.2
April 25, 2013
ISLA224S
Typical Performance Curves
All Typical Performance Characteristics apply under the following conditions unless otherwise noted: AVDD = OVDD = 1.8V, TA = +25°C, AIN = -2dBFS,
fIN = 105MHz, fSAMPLE = 250MSPS. (Continued)
FIGURE 27. SERDES DATA EYE at 4.375Gbps
FIGURE 28. SERDES BATHTUB at 1.0Gbps
FIGURE 29. SERDES BATHTUB at 3.0Gbps
FIGURE 30. SERDES BATHTUB at 4.375Gbps
FIGURE 31. SERDES HISTOGRAM at 1.0Gbps
FIGURE 32. SERDES HISTOGRAM at 3.0Gbps
14
FN7911.2
April 25, 2013
ISLA224S
Typical Performance Curves
All Typical Performance Characteristics apply under the following conditions unless otherwise noted: AVDD = OVDD = 1.8V, TA = +25°C, AIN = -2dBFS,
fIN = 105MHz, fSAMPLE = 250MSPS. (Continued)
FIGURE 33. SERDES HISTOGRAM at 4.375Gbps
Theory of Operation
Functional Description
The ISLA224S is based upon a 14-bit, 250MSPS ADC converter
core that utilizes a pipelined successive approximation
architecture (see Figure 34). The input voltage is captured by a
Sample-Hold Amplifier (SHA) and converted to a unit of charge.
Proprietary charge-domain techniques are used to successively
compare the input to a series of reference charges. Decisions
made during the successive approximation operations determine
the digital code for each input value. Digital error correction is also
applied.
Power-On Calibration
The ADC core(s) perform a self-calibration at start-up. An internal
power-on-reset (POR) circuit detects the supply voltage ramps
and initiates the calibration when the analog and digital supply
voltages are above a threshold. The following conditions must be
adhered to for the power-on calibration to execute successfully:
• A frequency-stable conversion clock must be applied to the
CLKP/CLKN pins
A user-initiated reset can subsequently be invoked in the event
that the above conditions cannot be met at power-up.
After the power supply has stabilized, the internal POR releases
RESETN and an internal pull-up pulls it high, which starts the
calibration sequence. If a subsequent user-initiated reset is
desired, the RESETN pin should be connected to an open-drain
driver with an off-state/high impedance state leakage of less
than 0.5mA to assure exit from the reset state so calibration can
start.
The calibration sequence is initiated on the rising edge of
RESETN, as shown in Figure 35. Calibration status can be
determined by reading the cal_status bit (LSB) at 0xB6. This bit is
‘0’ during calibration and goes to a logic ‘1’ when calibration is
complete. During calibration the JESD204 transmitter PLL is not
locked to the ADC sample clock, so the CML outputs will toggle at
an undetermined rate. Normal operation is resumed once
calibration is complete.
At 250MSPS the nominal calibration time is 280ms, while the
maximum calibration time is 550ms.
• DNC pins must not be connected
• SDO has an internal pull-up and should not be driven externally
• RESETN is pulled low by the ADC internally during POR.
External driving of RESETN is optional.
• SPI communications must not be attempted during
calibration, with the only exception of performing read
operations on the cal_done register at address 0xB6.
15
FN7911.2
April 25, 2013
ISLA224S
CLOCK
GENERATION
INP
2.5-BIT
2.5-BIT
FLASH
SHA
FLASH
INN
1.25V
+
–
6- STAGE
1.5-BIT/ STAGE
3- STAGE
1-BIT/ STAGE
3-BIT
FLASH
DIGITAL
ERROR
CORRECTION
FIGURE 34. ADC CORE BLOCK DIAGRAM
CLKN
CLKP
CALIBRATION
TIME
RESETN
CAL_STATUS
BIT
CALIBRATION
BEGINS
CALIBRATION
COMPLETE
FIGURE 35. CALIBRATION TIMING
User Initiated Reset
Recalibration of the ADC can be initiated at any time by driving
the RESETN pin low for a minimum of one clock cycle. An
open-drain driver with a drive strength in its high impedance
state of less than 0.5mA is recommended, as RESETN has an
internal high impedance pull-up to OVDD. As is the case during
power-on reset, RESETN and DNC pins must be in the proper
state for the calibration to successfully execute.
16
The performance of the ISLA224S changes with variations in
temperature, supply voltage or sample rate. The extent of these
changes may necessitate recalibration, depending on system
performance requirements. Best performance will be achieved
by recalibrating the ADC under the environmental conditions at
which it will operate.
A supply voltage variation of <100mV will generally result in an
SNR change of <0.5dBFS and SFDR change of <3dBc. In
situations where the sample rate is not constant, best results will
be obtained if the device is calibrated at the highest sample rate.
Reducing the sample rate by less than 80MSPS will typically
result in an SNR change of <0.5dBFS and an SFDR change of
<3dBc.
Figures 36 through 41 show the affect of temperature on SNR
and SFDR performance with power on calibration performed at
-40°C, +25°C, and +85°C. Each plot shows the variation of
SNR/SFDR across temperature after a single power on
calibration at -40°C, +25°C and +85°C. Best performance is
typically achieved by a user-initiated power on calibration at the
operating conditions, as stated earlier. However, it can be seen
that performance drift with temperature is not a very strong
function of the temperature at which the power on calibration is
performed.
FN7911.2
April 25, 2013
ISLA224S
Temperature Calibration
76
90
-2dBFS, 125MSPS
-1dBFS, 125MSPS
-2dBFS, 125MSPS
-2dBFS, 200MSPS
-1dBFS, 200MSPS
-2dBFS, 250MSPS
-1dBFS, 250MSPS
74
73
-2dBFS, 200MSPS
85
SFDR (dBc)
SNR (dBFS)
75
-1dBFS, 200MSPS
-1dBFS, 125MSPS
80
-2dBFS, 250MSPS
72
71
-40
-35
-30
TEMPERATURE (°C)
-25
-1dBFS, 250MSPS
75
-40
-20
-35
-30
FIGURE 36. TYPICAL SNR PERFORMANCE vs TEMPERATURE,
DEVICE CALIBRATED AT -40°C, fIN = 105MHz
-20
FIGURE 37. TYPICAL SFDR PERFORMANCE vs TEMPERATURE,
DEVICE CALIBRATED AT -40°C, fIN = 105MHz
76
90
-2dBFS, 200MSPS
-2dBFS, 125MSPS
-2dBFS, 125MSPS
-25
TEMPERATURE (°C)
-1dBFS, 125MSPS
75
SFDR (dBc)
SNR (dBFS)
85
74
-2dBFS, 200MSPS
-1dBFS, 200MSPS
73
-2dBFS, 250MSPS
-1dBFS, 200MSPS
80
-1dBFS, 250MSPS
-2dBFS, 250MSPS
-1dBFS, 125MSPS
72
71
-1dBFS, 250MSPS
5
10
15
20
25
30
35
40
75
45
5
10
15
TEMPERATURE (°C)
20
25
30
TEMPERATURE (°C)
35
40
45
FIGURE 39. TYPICAL SFDR PERFORMANCE vs TEMPERATURE,
DEVICE CALIBRATED AT +25°C, fIN = 105MHz
FIGURE 38. TYPICAL SNR PERFORMANCE vs TEMPERATURE,
DEVICE CALIBRATED AT +25°C, fIN = 105MHz
76
90
-2dBFS, 125MSPS
75
-1dBFS, 125MSPS
-2dBFS, 125MSPS
-2dBFS, 200MSPS
85
73
-2dBFS, 200MSPS
SFDR (dBc)
SNR (dBFS)
74
-1dBFS, 200MSPS
72
-2dBFS, 250MSPS
71
-1dBFS, 250MSPS
-2dBFS, 250MSPS
80
70
-1dBFS, 125MSPS
69
68
65
70
75
80
TEMPERATURE (°C)
FIGURE 40. TYPICAL SNR PERFORMANCE vs TEMPERATURE,
DEVICE CALIBRATED AT +85°C, fIN = 105MHz
17
85
75
65
70
-1dBFS, 250MSPS
75
-1dBFS, 200MSPS
80
85
TEMPERATURE (°C)
FIGURE 41. TYPICAL SFDR PERFORMANCE vs TEMPERATURE,
DEVICE CALIBRATED AT +85°C, fIN = 105MHz
FN7911.2
April 25, 2013
ISLA224S
Analog Input
A single fully differential input (VINP/VINN) connects to the
sample and hold amplifier (SHA) of each unit ADC. The ideal
full-scale input voltage is 2.0V, centered at the VCM voltage as
shown in Figure 42.
ADC
VINN
1.8
VINP
1.4
VCM
1.0V
1.0
FIGURE 45. DIFFERENTIAL AMPLIFIER INPUT
0.6
0.2
FIGURE 42. ANALOG INPUT RANGE
Best performance is obtained when the analog inputs are driven
differentially. The common-mode output voltage, VCM, should be
used to properly bias the inputs as shown in Figures 43 through
45. An RF transformer will give the best noise and distortion
performance for wideband and/or high intermediate frequency
(IF) inputs. Two different transformer input schemes are shown in
Figures 43 and 44.
ADT1-1WT
ADT1-1WT
1000pF
ADC
VCM
0.1µF
FIGURE 43. TRANSFORMER INPUT FOR GENERAL PURPOSE
APPLICATIONS
ADTL1-12
TX-2-5-1
1000pF
ADC
A differential amplifier, as shown in the simplified block diagram
in Figure 45, can be used in applications that require
DC-coupling. In this configuration, the amplifier will typically
dominate the achievable SNR and distortion performance.
Intersil’s new ISL552xx differential amplifier family can also be
used in certain AC applications with minimal performance
degradation. Contact the factory for more information.
When an over range occurs, the data sample output bits are held
at full scale (all 0’s or all 1’s), thus allowing the detection of this
condition in the receiver device.
Clock Input
The clock input circuit is a differential pair (see Figure 59). Driving
these inputs with a high level (up to 1.8VP-P on each input) sine or
square wave will provide the lowest jitter performance. A
transformer with 4:1 impedance ratio will provide increased drive
levels. The clock input is functional with AC-coupled LVDS, LVPECL,
and CML drive levels. To maintain the lowest possible aperture
jitter, it is recommended to have high slew rate at the zero crossing
of the differential clock input signal.
The recommended drive circuit is shown in Figure 46. A duty
range of 40% to 60% is acceptable. The clock can be driven
single-ended, but this will reduce the edge rate and may impact
SNR performance. The clock inputs are internally self-biased to
AVDD/2 through a Thevenin equivalent of 10kΩ to facilitate AC
coupling.
TC4-19G2+
VCM
1000pF
CLKP
1000pF
FIGURE 44. TRANSMISSION-LINE TRANSFORMER INPUT FOR
HIGH IF APPLICATIONS
This dual transformer scheme is used to improve common-mode
rejection, which keeps the common-mode level of the input
matched to VCM. The value of the shunt resistor should be
determined based on the desired load impedance. The
differential input resistance of the ISLA224S is 600Ω.
The SHA design uses a switched capacitor input stage (see
Figure 58), which creates current spikes when the sampling
capacitance is reconnected to the input voltage. This causes a
disturbance at the input, which must settle before the next
sampling point. Lower source impedance will result in faster
settling and improved performance. Therefore a 2:1 or 1:1
transformer and low shunt resistance are recommended for
optimal performance.
18
0.01µF
200
CLKN
1000pF
1000pF
FIGURE 46. RECOMMENDED CLOCK DRIVE
A selectable 2x or 4x frequency divider is provided in series with the
clock input. The divider can be used in the 2x mode with a sample
clock equal to twice the desired sample rate or in 4x mode with a
sample clock equal to four times the desired sample rate. Use of the
2x or 4x frequency divider enables the use of the Phase Slip feature,
which enables the system to be able to select the phase of the
divide by 2 or divide by 4 that causes the ADC to sample the
analog input.
FN7911.2
April 25, 2013
ISLA224S
Voltage Reference
TABLE 1. CLKDIV PIN SETTINGS
CLKDIV PIN
DIVIDE RATIO
AVSS
2
Float
1
AVDD
4
A temperature compensated internal voltage reference provides
the reference charges used in the successive approximation
operations. The full-scale range of each ADC is proportional to
the reference voltage. The nominal value of the voltage reference
is 1.25V.
The clock divider can also be controlled through the SPI port,
which overrides the CLKDIV pin setting. See “SPI Physical
Interface” on page 25. A delay-locked loop (DLL) generates
internal clock signals for various stages within the charge
pipeline. If the frequency of the input clock changes, the DLL may
take up to 52μs to regain lock at 250MSPS. The lock time is
inversely proportional to the sample rate.
The DLL has two ranges of operation, slow and fast. The slow
range can be used for ADC core sample rates between 40MSPS
and 100MSPS, while the default fast range can be used from
80MSPS to the maximum specified sample rate. The lane data
rate is related to the ADC core sample rate by a relationship that
is defined by the JESD204 transmitter configuration, and has
additional frequency constraints; see“JESD204 Transmitter” on
page 20 for additional details.
Jitter
In a sampled data system, clock jitter directly impacts the
achievable SNR performance. The theoretical relationship
between clock jitter (tJ) and SNR is shown in Equation 1 and is
illustrated in Figure 47.
1
SNR = 20 log 10 ⎛ --------------------⎞
⎝ 2πf t ⎠
IN J
(EQ. 1)
100
95
tj = 0.1ps
90
14 BITS
SNR (dB)
85
80
tj = 1ps
75
tj = 10ps
60
10 BITS
tj = 100ps
55
50
1M
10M
100M
INPUT FREQUENCY (Hz)
1G
FIGURE 47. SNR vs CLOCK JITTER
This relationship shows the SNR that would be achieved if clock
jitter were the only non-ideal factor. In reality, achievable SNR is
limited by internal factors such as linearity, aperture jitter and
thermal noise as well. Internal aperture jitter is the uncertainty in
the sampling instant. The internal aperture jitter combines with
the input clock jitter in a root-sum-square fashion, since they are
not statistically correlated, and this determines the total jitter in
the system. The total jitter, combined with other noise sources,
then determines the achievable SNR.
19
The digital outputs are in CML format, and feature analog and
digital characteristics compliant with the JESD204 standard
requirements.
Power Dissipation
The power dissipated by the device is dependent on the ADC
sample rate and the number of active lanes in the link. There is a
fixed bias current drawn from the analog supply for the ADC,
along with a fixed bias current drawn from the digital supply for
each active lane. The remaining power dissipation is linearly
related to the sample rate.
Nap/Sleep
Portions of the device may be shut down to save power during
times when operation of the ADC is not required. Two power saving
modes are available: Nap, and Sleep. Nap mode reduces power
dissipation significantly while taking a very short time to return to
functionality. Sleep mode reduces power consumption drastically
while taking longer to return to functionality.
In Nap mode the JESD204 lanes will continue to produce valid
encoded data, allowing the link to remain active and thus return to
a functional state quickly. The data transmitted over the lanes in
nap mode is the last valid ADC sample, repeated until leaving nap
mode. The 8b/10b encoder’s running disparity will prevent the
potentially long time repetition of this last valid sample from
creating DC bias on the lane. In sleep mode the JESD204 lanes will
be deactivated to conserve power. Thus, sometime after wake up
code group alignment will be required to reestablish the link.
The input clock should remain running and at a fixed frequency
during Nap or Sleep, and CSB should be high. The JESD204 link
will only remain established during nap mode if the input clock
continues to remain stable during the nap period.
12 BITS
70
65
Digital Outputs
By default after the device is powered on, the operational state is
controlled by the NAPSLP pin as shown in Table 2. Please note
that power on calibration occurs at power up time regardless of
the state of the NAPSLP pin; immediately following this power on
calibration routine the device will enter nap or sleep state if the
NAPSLP pin voltage dictates it is to do so.
TABLE 2. NAPSLP PIN SETTINGS
NAPSLP PIN
MODE
AVSS
Normal
Float
Nap
AVDD
Sleep
The power-down mode can also be controlled through the SPI port,
which overrides the NAPSLP pin setting. However, if the ADC is
powered-on with the NAPSLP pin in either Nap or Sleep modes, the
FN7911.2
April 25, 2013
ISLA224S
pin must be first set to Normal before the SPI port will be enabled.
Therefore, before the SPI port can be used to override the NAPSLP
pin setting, the ADC must have been put into Normal mode at
least once using the NAPSLP pin. Further details on the SPI port
are contained in “Serial Peripheral Interface” on page 25.
–Full Scale 00 0000 0000 0000 10 0000 0000 0000 00 0000 0000 0000
Data Format
–Full Scale 00 0000 0000 0001 10 0000 0000 0001 00 0000 0000 0001
+ 1LSB
Output data can be presented in three formats: two’s
complement(default), Gray code and offset binary. The data
format can be controlled through the SPI port by writing to
address 0x73. Details on this are contained in “Serial Peripheral
Interface” on page 25.
Offset binary coding maps the most negative input voltage to
code 0x000 (all zeros) and the most positive input to 0xFFF (all
ones). Two’s complement coding simply complements the MSB
of the offset binary representation.
When calculating Gray code the MSB is unchanged. The remaining
bits are computed as the XOR of the current bit position and the
next most significant bit. Figure 48 shows this operation.
BINARY
13
12
11
••••
1
0
13
12
••••
11
1
Converting back to offset binary from Gray code must be done
recursively, using the result of each bit for the next lower bit as
shown in Figure 49.
13
12
11
OFFSET BINARY
TWO’S
COMPLEMENT
GRAY CODE
Mid–Scale 10 0000 0000 0000 00 0000 0000 0000 11 0000 0000 0000
+Full Scale 11 1111 1111 1110 01 1111 1111 1110 10 0000 0000 0001
– 1LSB
+Full Scale 11 1111 1111 1111 01 1111 1111 1111 10 0000 0000 0000
Clock Divider Synchronous Reset
The function of clock divider synchronous reset is available as a
SPI-programmable overloaded function on the SYNCP and SYNCN
pins. Given that the clock divider reset and SYNC features have the
same electrical and timing requirements, this overloading allows
the system to generate only a single well timed signal with respect
to the ADC sample clock and select the ADC’s interpretation of the
signal as a SPI-programmable option (see SPI register 0x77
description for more information). By default the SYNCP and
SYNCN pins will function as the JESD204 SYNC~.
Soft Reset
0
FIGURE 48. BINARY TO GRAY CODE CONVERSION
GRAY CODE
INPUT
VOLTAGE
The use of clock divider reset function is a requirement in a
system that uses the ISLA214S50, ISLA214S35, or CLKDIV = 2
or 4 and also requires time alignment or deterministic latency of
multiple devices. Please contact the factory for more details
about this feature and its usage.
••••
GRAY CODE
TABLE 3. INPUT VOLTAGE TO OUTPUT CODE MAPPING
••••
1
0
Soft reset is a function intended to be used when the power on
reset is to be re-run. An application may decide to issue a soft
calibration command after significant temperature change or
after a change in the sample rate frequency to optimize
performance under the new condition.
Soft reset is issued by writing the Soft Reset bit at SPI address
0x00. Soft reset is a self-resetting bit in that will automatically
return to 0 once the power on calibration has completed.
JESD204 Transmitter
Overview
••••
The conversion data is presented by a JESD204B-compliant
SERDES interface. The SERDES lane data rate supports typical
speeds up to 4.375Gbps, exceeding the 3.125Gbps maximum
specified by the JESD204 rev A standard. Two packing modes are
supported: Efficient and Simple. A SYNC input is included, which
is used for lane initialization as well as time alignment of
multiple converter devices. AC coupling of the SERDES lane(s) on
the board is required. A block diagram of this SERDES
transmitter is shown in Figure 50.
••••
BINARY
13
12
11
••••
1
FIGURE 49. GRAY CODE TO BINARY CONVERSION
Mapping of the input voltage to the various data formats is
shown in Table 3..
20
0
For more information about the standardized characteristics and
features of a JESD204 interface, please see JESD204 rev A and rev
B standards. For application design support, including evaluation kit
schematics and layout, reference FPGA project(s), and simulation
models for functionality and signal integrity, please contact the
factory and/or view application notes on the Intersil website.
FN7911.2
April 25, 2013
ISLA224S
SERDES Block
Link Layer
Sample Data
Analog
Input
Analog
Input
Sample
Clock
Transport
Layer
Scrambler
1+x14+x15
Encoder
8/10
Lane 0
SER
Logic
Sample Data
PLL
Multiply
Clock
Management
- Code group Synchronization
- Alignment Characters
- Initial Lane Synchronization
- Etc
SYNC
Link Layer
Lane 1
Link Layer
Lane 2
FIGURE 50. SERDES TRANSMITTER BLOCK DIAGRAM
To maximize flexibility at the system level, two transport layer
packing modes are supported: simple and efficient. These two
modes allow the system designer flexibility to trade off between
the number of lanes to support a given throughput, the data rate
of these lanes, and the complexity of the receiver. This translates
directly into providing system level trade-offs between cost,
power, and resource usage of the receiver and complexity of the
solution.
Simple mode packs informationless bits onto each ADC sample
to form full 16-bit data. In simple mode packing, the frame clock
and ADC sample clock are the same frequency, easing frequency
scaling requirements at the system level, but decreasing the
payload efficiency of the lanes. Decreased payload efficiency of
the lanes increases the lane data rate required to support a given
throughput, and may require additional lanes to support a given
configuration. The degree of payload efficiency loss is dependent
on the ADC resolution.
Efficient mode packs sequential ADC samples into a contiguous
block of an integer number of octets, and then slices the block
into the octets for transport. This mode always achieves the
theoretical maximum payload of the lanes (80%) regardless of
the resolution of the ADC and the number of lanes used. This
mode provides the minimum number of lanes at the minimum
data rate that is theoretically possible given the 8b/10b
encoding used in JESD204 systems. In efficient packing mode,
frame clock and the ADC sample clock have an M/N relationship,
where M and N are small integers and vary depending on the
ADC resolution and number of lanes selected. Efficient mode
packing may require additional frequency scaling elements
(internal FPGA PLLs or discrete frequency scaling devices) to
generate the frame clock for the receiving device.
21
The default configuration for this device is efficient packing
mode. Reconfiguration into the simple packing mode is
accomplished by programming the JESD204 parameters via the
SPI bus. See Table 5 for the full list of parameters values for each
mode and product. Via SPI, the JESD204 transmitter is highly
configurable, supporting efficient to simple mode packing
reconfiguration as well as “downgrading” a given product’s
JESD204 interface. For example, reconfiguring a 3-lane product
into 2 lanes (with each running faster than with 3 lanes), or
reducing the resolution of the ADC(s) to slow down the lane data
rate in systems where the full ADC resolution is not required, are
supported. Please contact Intersil sales support for a full list of
downgradeable configurations that are supported.
Signal integrity plots, including data eye, BER bathtub curves,
and edge histogram plots versus lane data rate can be found in
the “Typical Performance Curves” on page 10.
Initial Lane Alignment
The link initialization process is started by asserting the SYNC~
signal to the ADC device. This assertion causes the JESD204
transmitter to generate comma characters, which are used by
the receiver to accomplish code group synchronization (bit and
octet alignment, respectively). Once code group synchronization
is detected in the receiver, it de-asserts the SYNC~ signal,
causing the JESD204 transmitter to generate the initial lane
alignment sequence (ILA). The ILA is comprised of 4
multi-frames of data in a standard format, with the length of
each multi-frame determined by the K parameter as
programmed into the SPI JESD204 parameter table. The ILA
includes standard control character markers that can be used to
perform channel bonding in the receiving device if desired. The
2nd multi-frame includes the full JESD204 parameter data,
FN7911.2
April 25, 2013
ISLA224S
allowing the receiver to auto-detect the lane configuration if
desired.
After completion of the ILA the JESD204 transmitter begins
transmitting ADC sample data. Continuous link and lane
alignment monitoring is accomplished via an octet substitution
scheme. The last octet in each frame, if identical to the last octet
in the previous frame, is replaced with a specific control
character. If both sides of the link support lane synchronization,
the last octet in each multi-frame, if identical to the last octet in
the previous frame, is replaced with a different specific control
character. A more complete description of the link initialization
sequence, including finite state machine implementation, can be
found in the JESD204 rev A standard.
LANE DATA RATE
The lane data rate for this product family is a function of the ADC
sample rate, the number of SERDES lanes used, and packing
mode selected in the SERDES transmitter. Figure 51 illustrates
the relationship between ADC sample rate and SERDES lane rate
for various transmitter configurations. The SERDES can typically
operate from lane rates of 1 to over 4.375Gbs. For each ADC
speed grade, the SERDES lanes are tested at its maximum ADC
sample rate using three lane efficient packing as well as twolane, efficient packing for the 125MSPS speed version.
LANE DATA RATE CHART
4500
LANE RATE (MBPS)
4000
3500
3000
4.375 GBPS
3.125 GBPS (JESD204)
2 Lanes (Simple Packing)
2500
2000
3 Lanes (Simple Packing)
1500
1000
50
70
90
3 Lanes (Efficient Packing)
2 Lanes (Efficient Packing)
110 130 150 170 190 210 230 250
ADC SAMPLE RATE (MSPS)
FIGURE 51. LANE DATA RATE AS A FUNCTION OF PACKING AND
ADC SAMPLE RATE
SCRAMBLER
The bypassable scrambler is compliant with the scrambler
defined in the JESD204 rev A standard.
This implementation seeds the scrambler with the initial lane
alignment sequence, such that the first two octets following the
sequence can be properly descrambled if the receiver also
passes the lane alignment sequence through its descrambler.
Even if the receiver does not implement this detail, the 3rd and
subsequent octets can be descrambled to yield ADC data due to
the self-synchronizing nature of the scrambler used.
22
MULTI-CHIP TIME ALIGNMENT
The JESD204 standard (in various revisions) provides the
capability to time align multiple JESD204 ADC devices to a single
logic device (FPGA or ASIC). This feature is critical in many
applications that cannot tolerate the variable latency of the
JESD204 link, and that must process pipeline depth correct data
from more than one ADC device.
Time alignment of multiple devices provides the capability to
align samples from multiple JESD204 ADC devices in the system
in a pipeline-depth correct manner, thus enabling the system to
analyze the ADC data from multiple devices while eliminating the
variable latency of the JESD204 link as a concern. This capability
enables configurations of JESD204 ADCs as IQ, interleave,
and/or simultaneously-sampled converters.
This ADC family uses the asserted to de-asserted SYNC~
transition as the absolute time event with which to generate a
known sequence of characters at the JESD204 transmitter of
equal pipeline depth between all ADC devices in the system to be
time aligned. This is consistent with the JESD204 rev B
subclass 2 device definition.
Test Patterns
The complexity of the JESD204 interface merits much more test
pattern capability than less complex parallel interfaces. This
device family consequently supports a much wider range of test
patterns than previous ADC families.
Supported test patterns include both transport and link layer
patterns. Transport layer patterns are passed through the
transport layer of the JESD204 transmitter, following the same
sequence of being packed and sliced into octets as the ADC
sample data. Link layer test patterns bypass the transport layer
and are injected directly into the 8b/10b encoder, serialized, and
sent out of the physical media. Test pattern generation is
controlled through SPI register 0xC0.
Link layer PRBS patterns are standard PRBS patterns that can be
used with built-in standard PRBS checkers in, for example, FPGA
SERDES-capable pins.
All transport layer test patterns re-initialize their phase when the
SYNC~ de-assertion occurs; consequently, a system that provides
a well-timed SYNC~ signal with respect to the ADC sample clock
can expect transport layer test patterns to have consistent phase
with respect to that de-assertion, which can be a significant aid
when debugging the system.
FN7911.2
April 25, 2013
ISLA224S
TABLE 4. JESD204 CONFIGURATIONS AND CLOCK FREQUENCIES
LANE DATA RATE MULTIPLIER FROM ADC SAMPLE CLOCK
RATE
ADC SAMPLE CLOCK RANGE (MHz)
LANE DATA RATE (GBPS)
100-250 (Efficient Packing) 3 Lanes
(14-bits)*(2 ADC channels)*(10/8 encoder overhead)/(3
lanes) = (280/24) = 11.6667
1.16667 to 2.916675
57-250 (Efficient Packing) 2 Lanes
(14-bits)*(2 ADC channels)*(10/8 encoder overhead)/(2
lanes) = (280/16) = 17.5
1.00 to 4.375
(14-bits+2-bit tail)*(2 ADC channels)*(10/8 encoder
overhead)/(2 lanes) = (320/16) = 20
1.00 to 4.375
50-219(Simple Packing) 2 Lanes
TABLE 5. JESD204 PARAMETERS
PACKING
MODE
Efficient
Efficient
Simple
NUMBER
JESD204
OF LANES PARAMETER
3
2
2
ENCODED
CF = 0
0
CS = 0
0
F=7
6
HD = 0
0
L=3
2
M=2
1
N = 14
13
N' = 14
13
S=6
5
K >= 3
>= 2
CF = 0
0
CS = 0
0
F=7
6
HD = 0
0
L=2
1
M=2
1
N = 14
13
N' = 14
13
S=4
3
K >= 3
>=2
CF = 0
0
CS = 0
0
F=2
1
HD = 0
0
L=2
1
M=2
1
N = 14
13
N' = 16
15
S=1
0
K >= 9
>= 8
23
JESD204 PARAMETERS AND FRAME MAP (Notes 16, 17, 18)
C0S0[13:6] C0S0[5:0]
C0S1[13:12]
C0S4[13:6] C0S4[5:0]
C0S5[13:12]
C1S2[13:6] C1S2[5:0]
C1S3[13:12]
C0S0[13:6] C0S0[5:0]
C0S1[13:12]
C1S0[13:6] C1S0[5:0]
C1S1[13:12]
C0S1[11:4] C0S1[3:0]
C0S2[13:10]
C0S5[11:4] C0S5[3:0]
C1S0[13:10]
C1S3[11:4] C1S3[3:0]
C1S4[13:10]
C0S1[11:4] C0S1[3:0]
C0S2[13:10]
C1S1[11:4] C1S1[3:0]
C1S2[13:10]
C0S2[9:2] C0S2[1:0]
C0S3[7:0]
C0S3[13:8]
C1S0[9:2] C1S0[1:0]
C1S1[7:0]
C1S1[13:8]
C1S4[9:2] C1S4[1:0]
C1S5[7:0]
C1S5[13:8]
C0S2[9:2] C0S2[1:0]
C0S3[7:0]
C0S3[13:8]
C1S2[9:2] C1S2[1:0]
C1S3[7:0]
C1S3[13:8]
C0S0[13:6] C0S0[5:0]
TT
C1S0[13:6] C1S0[5:0]
TT
FN7911.2
April 25, 2013
ISLA224S
TABLE 5. JESD204 PARAMETERS (Continued)
PACKING
MODE
NUMBER
JESD204
OF LANES PARAMETER
ENCODED
JESD204 PARAMETERS AND FRAME MAP (Notes 16, 17, 18)
NOTES:
16. The JESD204 parameters are shown as their actual values, with the JESD204 encoded values (i.e., the values that are programmed into the SPI
registers) in the next column over. Typically values that must always be greater than 1 are encoded as value minus 1, and so on.
17. Frame map format decoder: "CxSy[a:b]" = Converter x, Sample y, bits a through b. For example, "C0S0[13:6]" = Converter 0, Sample 0, bits 13 through
6, etc. "T" = Tail bit (information-less bit packed in the transport layer mapping to form octets).
18. The topmost lane in the graphical frame map is Lane0, followed by Lane1 and Lane 2 (for 3-lane configurations).
CSB
SCLK
SDIO
R/W
W1
W0
A12
A11
A1
A10
A0
D7
D6
D5
D4
D3
D2
D1
D0
D2
D3
D4
D5
D6
D7
FIGURE 52. MSB-FIRST ADDRESSING
CSB
SCLK
SDIO
A0
A1
A2
A11
A12
W0
W1
R/W
D1
D0
FIGURE 53. LSB-FIRST ADDRESSING
tDSW
CSB
tDHW
tS
tCLK
tHI
tH
tLO
SCLK
SDIO
R/W
W1
W0
A12
A11
A10
A9
A8
A7
D5
D4
D3
D2
D1
D0
SPI WRITE
FIGURE 54. SPI WRITE
24
FN7911.2
April 25, 2013
ISLA224S
tDSW
CSB
tCLK
tHI
tH
tDVR
tS
tDHW
tLO
SCLK
WRITING A READ COMMAND
READING DATA ( 3 WIRE MODE )
SDIO
R/W
W1
W0
A12
A11
A10
A9
A2
A1
A0
D7
D6
D3
D2
D1 D0
( 4 WIRE MODE)
SDO
D7
D3
D2
D1 D0
SPI READ
FIGURE 55. SPI READ
CSB STALLING
CSB
SCLK
SDIO
INSTRUCTION/ADDRESS
DATA WORD 1
DATA WORD 2
FIGURE 56. 2-BYTE TRANSFER
LAST LEGAL
CSB STALLING
CSB
SCLK
SDIO
INSTRUCTION/ADDRESS
DATA WORD 1
DATA WORD N
FIGURE 57. N-BYTE TRANSFER
Serial Peripheral Interface
SPI Physical Interface
A serial peripheral interface (SPI) bus is used to facilitate
configuration of the device and to optimize performance. The SPI
bus consists of chip select (CSB), serial clock (SCLK) serial data
output (SDO), and serial data input/output (SDIO). The maximum
SCLK rate is equal to the ADC sample rate (fSAMPLE) divided by 7
for write operations and fSAMPLE divided by 16 for reads. There is
no minimum SCLK rate.
The serial clock pin (SCLK) provides synchronization for the data
transfer. By default, all data is presented on the serial data
input/output (SDIO) pin in three-wire mode. The state of the SDIO
pin is set automatically in the communication protocol
(described in the following). A dedicated serial data output pin
(SDO) can be activated by setting 0x00[7] high to allow operation
in four-wire mode.
The following sections describe various registers that are used to
configure the SPI or adjust performance or functional parameters.
Many registers in the available address space (0x00 to 0xFF) are
not defined in this document. Additionally, within a defined
register there may be certain bits or bit combinations that are
reserved. Undefined registers and undefined values within defined
registers are reserved and should not be selected. Setting any
reserved register or value may produce indeterminate results.
The SPI port operates in a half duplex master/slave
configuration, with the ADC functioning as a slave. Multiple slave
devices can interface to a single master in three-wire mode only,
since the SDO output of an unaddressed device is asserted in
four wire mode.
25
The chip-select bar (CSB) pin determines when a slave device is
being addressed. Multiple slave devices can be written to
concurrently, but only one slave device can be read from at a
given time (again, only in three-wire mode). If multiple slave
devices are selected for reading at the same time, the results will
be indeterminate.
FN7911.2
April 25, 2013
ISLA224S
The communication protocol begins with an instruction/address
phase. The first rising SCLK edge following a high-to-low
transition on CSB determines the beginning of the two-byte
instruction/address command; SCLK must be static low before
the CSB transition. Data can be presented in MSB-first order or
LSB-first order. The default is MSB-first, but this can be changed
by setting 0x00[6] high. Figures 52 and 53 show the appropriate
bit ordering for the MSB-first and LSB-first modes, respectively. In
MSB-first mode, the address is incremented for multi-byte
transfers, while in LSB-first mode it’s decremented.
In the default mode, the MSB is R/W, which determines if the
data is to be read (active high) or written. The next two bits, W1
and W0, determine the number of data bytes to be read or
written (see Table 6). The lower 13 bits contain the first address
for the data transfer. This relationship is illustrated in Figure 54,
and timing values are given in “Switching Specifications” on
Page 8.
After the instruction/address bytes have been read, the
appropriate number of data bytes are written to or read from the
ADC (based on the R/W bit status). The data transfer will
continue as long as CSB remains low and SCLK is active. Stalling
of the CSB pin is allowed at any byte boundary
(instruction/address or data) if the number of bytes being
transferred is three or less. For transfers of four bytes or more,
CSB is allowed to stall in the middle of the instruction/address
bytes or before the first data byte. If CSB transitions to a high
state after that point the state machine will reset and terminate
the data transfer.
TABLE 6. BYTE TRANSFER SELECTION
[W1:W0]
BYTES TRANSFERRED
00
1
01
2
10
3
11
4 or more
Figures 56 and 57 illustrate the timing relationships for 2-byte
and N-byte transfers, respectively. The operation for a 3-byte
transfer can be inferred from these diagrams.
SPI Configuration
ADDRESS 0X00: CHIP_PORT_CONFIG
Bit ordering and SPI reset are controlled by this register. Bit order
can be selected as MSB to LSB (MSB first) or LSB to MSB (LSB
first) to accommodate various micro controllers.
Bit 7 SDO Active
Bit 6 LSB First
Setting this bit high configures the SPI to interpret serial data
as arriving in LSB to MSB order.
Bit 5 Soft Reset
Setting this bit high resets all SPI registers to default values.
Bits 3:0 These bits should always mirror bits 4:7 to avoid
ambiguity in bit ordering.
ADDRESS 0X02: BURST_END
If a series of sequential registers are to be set, burst mode can
improve throughput by eliminating redundant addressing. The
burst is ended by pulling the CSB pin high. Setting the burst_end
address determines the end of the transfer. During a write
operation, the user must be cautious to transmit the correct
number of bytes based on the starting and ending addresses.
Bits 7:0 Burst End Address
This register value determines the ending address of the burst
data.
Device Information
ADDRESS 0X08: CHIP_ID
ADDRESS 0X09: CHIP_VERSION
The generic die identifier and a revision number, respectively, can
be read from these two registers.
Device Configuration/Control
A common SPI map, which can accommodate single-channel or
multi-channel devices, is used for all Intersil ADC products.
ADDRESS 0X20: OFFSET_COARSE_COREA
ADDRESS 0X21: OFFSET_FINE_COREA
The input offset of ADC coreA can be adjusted in fine and coarse
steps. Both adjustments are made via an 8-bit word as detailed
in Table 7. The data format is twos complement.
The default value of each register will be the result of the
self-calibration after initial power-up. If a register is to be
incremented or decremented, the user should first read the
register value then write the incremented or decremented value
back to the same register. Bit 0 in register 0xFE must be set high
to enable updates written to 0x20 and 0x21 to be used by the
ADC.(See description for 0xFE)
TABLE 7. OFFSET ADJUSTMENTS
CoreA
CoreB
PARAMETER
0x20[7:0]
0x26[7:0]
COARSE OFFSET
0x21[7:0]
0x27[7:0]
FINE OFFSET
Steps
255
255
–Full Scale (0x00)
-133LSB (-47mV)
-5LSB (-1.75mV)
Mid–Scale (0x80)
0.0LSB (0.0mV)
0.0LSB
+Full Scale (0xFF)
+133LSB (+47mV)
+5LSB (+1.75mV)
Nominal Step Size
1.04LSB (0.37mV)
0.04LSB (0.014mV)
ADDRESS 0X22: GAIN_COARSE_COREA
ADDRESS 0X23: GAIN_MEDIUM_COREA
ADDRESS 0X24: GAIN_FINE_COREA
Bit 4 Reserved
This bit should always be set high.
26
Gain of the ADC core can be adjusted in coarse, medium and fine
steps. Coarse gain is a 4-bit adjustment while medium and fine
FN7911.2
April 25, 2013
ISLA224S
are 8-bit. Multiple Coarse Gain Bits can be set for a total
adjustment range of ±4.2%. (‘0011’ ≅ -4.2% and ‘1100’ ≅ +4.2%)
It is recommended to use one of the coarse gain settings (-4.2%,
-2.8%, -1.4%, 0, 1.4%, 2.8%, 4.2%) and fine-tune the gain using the
registers at 0x0023 and 0x24.
The default value of each register will be the result of the
self-calibration after initial power-up. If a register is to be
incremented or decremented, the user should first read the
register value then write the incremented or decremented value
back to the same register. Bit 0 in register 0xFE must be set high
to enable updates written to 0x23 and 0x24 to be used by the
ADC.(See description for 0xFE).
TABLE 8. COARSE GAIN ADJUSTMENT
0x22[3:0] CoreA
0x26[3:0] CoreB
NOMINAL COARSE GAIN ADJUST
(%)
Bit3
+2.8
Bit2
+1.4
Bit1
-2.8
Bit0
-1.4
ADDRESS 0X26: OFFSET_COARSE_COREB
ADDRESS 0X27: OFFSET_FINE_COREB
The input offset of ADC coreB can be adjusted in fine and coarse
steps in the same way that offset for coreA can be adjusted. Both
adjustments are made via an 8-bit word as detailed in Table 7.
The data format is two’s complement.
The default value of each register will be the result of the
self-calibration after initial power-up. If a register is to be
incremented or decremented, the user should first read the
register value then write the incremented or decremented value
back to the same register. Bit 0 in register 0xFE must be set high
to enable updates written to 0x26 and 0x27 to be used by the
ADC.(See description for 0xFE)
ADDRESS 0X28: GAIN_COARSE_COREB
ADDRESS 0X29: GAIN_MEDIUM_COREB
ADDRESS 0X2A: GAIN_FINE_COREB
TABLE 9. MEDIUM AND FINE GAIN ADJUSTMENTS
Gain of ADC coreB can be adjusted in coarse, medium and fine
steps in the same way that coreA can be adjusted. Coarse gain is a
4-bit adjustment while medium and fine are 8-bit. Multiple Coarse
Gain Bits can be set for a total adjustment range of ±4.2%. Bit 0 in
register 0xFE must be set high to enable updates written to 0x29
and 0x2A to be used by the ADC.(See description for 0xFE)
CoreA
CoreB
PARAMETER
0x23[7:0]
0x29[7:0]
MEDIUM GAIN
0x24[7:0]
0x2A[7:0]
FINE GAIN
Steps
256
256
–Full Scale (0x00)
-2%
-0.20%
ADDRESS 0X71: PHASE_SLIP
Mid–Scale (0x80)
0.00%
0.00%
When using the clock_divide feature, the sample clock edge that
the ADC uses to sample the analog input signal can be one of
several different edges on the incoming higher frequency sample
clock. For example, in clock_divide = 2 mode, every other
incoming sample clock edge gets used by the ADC to sample the
analog input. The phase_slip feature allows the system to control
which edge of the incoming sample clock signals gets used to
cause the sampling event, by “slipping” the sampling event by
one input clock period each time phase_slip is asserted.
+Full Scale (0xFF)
+2%
+0.2%
Nominal Step Size
0.016%
0.0016%
ADDRESS 0X25: MODES
Two distinct reduced power modes can be selected. By default,
the tri-level NAPSLP pin can select normal operation, nap or
sleep modes (refer to"Nap/Sleep" on page 19). This functionality
can be overridden and controlled through the SPI. However, if
the ADC is powered-on with the NAPSLP pin in either Nap or
Sleep modes, the pin must first be set to Normal before the SPI
port will be enabled. Therefore, before the SPI port can be used
to override the NAPSLP pin setting, the ADC must have been put
into Normal mode at least once using the NAPSLP pin. This
register is not changed by a Soft Reset.
TABLE 10. POWER-DOWN CONTROL
Global Device Configuration/Control
The clkdivrst feature can work in conjunction with phase_slip.
After well-timed assertion of the clkdivrst signal (via overloading
on the SYNC inputs), the sampling edge position with respect to
the incoming clock rate will have been reset, allowing the system
to “slip” whatever desired number of incoming clock periods
from a known state.
ADDRESS 0X72: CLOCK_DIVIDE
VALUE
0x25[2:0]
POWER DOWN MODE
000
Pin Control
001
Normal Operation
The ADC has a selectable clock divider that can be set to divide
by two or one (no division). By default, the tri-level CLKDIV pin
selects the divisor This functionality can be overridden and
controlled through the SPI, as shown in Table 11. This register is
not changed by a Soft Reset.
010
Nap Mode
TABLE 11. CLOCK DIVIDER SELECTION
100
Sleep Mode
27
VALUE
0x72[2:0]
CLOCK DIVIDER
000
Pin Control
001
Divide by 1
FN7911.2
April 25, 2013
ISLA224S
TABLE 11. CLOCK DIVIDER SELECTION (Continued)
VALUE
0x72[2:0]
CLOCK DIVIDER
010
Divide by 2
100
Divide by 4
Other
Not Allowed
ADDRESS 0X73: OUTPUT_MODE_A
The output_mode_A register controls the logical coding of the
sample data. Data can be coded in three possible formats: two’s
complement(default), Gray code or offset binary. See Table 12.
This register is not changed by a Soft Reset.
be read after POR at calibration, unlike the other registers on
chip, which can’t be read until calibration is complete.
DEVICE TEST
The device can produce preset or user defined patterns on the
digital outputs to facilitate in-situ testing. A user can pick from
preset built-in patterns by writing to the output test mode field
[7:4] at 0xC0 or user defined patterns by writing to the user test
mode field [2:0] at 0xC0. The user defined patterns should be
loaded at address space 0xC1 through 0xD0, see the “SPI
Memory Map” on page 31 for more detail. The test mode is
enabled asynchronously to the sample clock, therefore several
sample clock cycles may elapse before the data is present on the
output bus.
ADDRESS 0XC0: TEST_IO
TABLE 12. OUTPUT FORMAT CONTROL
VALUE
0x73[2:0]
OUTPUT FORMAT
000
Two’s Complement (Default)
010
Gray Code
100
Offset Binary
Bits 7:4 Output Test Mode
These bits set the test mode according to the description in “SPI
Memory Map” on page 31.
Bits 2:0 User Test Mode
ADDRESS 0X74: OUTPUT_MODE_B
Bit 6 DLL Range
This bit sets the DLL operating range to fast (default) or slow.
Internal clock signals are generated by a delay-locked loop (DLL),
which has a finite operating range. Table 13 shows the allowable
sample rate ranges for the slow and fast settings.
The three LSBs in this register determine the test pattern in
combination with registers 0xC1 through 0xD0. Refer to the “SPI
Memory Map” on page 31.
ADDRESS 0XC1: USER_PATT1_LSB
ADDRESS 0XC2: USER_PATT1_MSB
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 1.
ADDRESS 0XC3: USER_PATT2_LSB
TABLE 13. DLL RANGES
DLL RANGE
MIN
MAX
UNIT
ADDRESS 0XC4: USER_PATT2_MSB
Slow
40
100
MSPS
Fast
80
250
MSPS
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 2
ADDRESS 0X77: SYNC_FUNCTION
ADDRESS 0XC5: USER_PATT3_LSB
ADDRESS 0XC6: USER_PATT3_MSB
BIT 0 CLKDIVRST
This bit controls the functionality of the SYNCP, SYNCN pins on
this device. By default, this bit equals ‘0’, which means that the
functionality of the SYNCP, SYNCN pins is the JESD204 SYNC.
Setting this bit equal to ‘1’ modifies the functionality of the
SYNCP, SYNCN pins to be clkdivrst, which is a synchronous
divider reset on all internal dividers in the device. Usage of this
clkdivrst functionality is required to support multi-chip time
alignment and deterministic latency for devices that use
interleaved product configurations (ISLA214S50 and
ISLA214S35), and for any other product configuration that uses
clkdiv > 1. In both states, the setup and hold times with respect
to the sample clock remain the same. Contact the factory for
more details.
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 3.
ADDRESS 0XC7: USER_PATT4_LSB
ADDRESS 0XC8: USER_PATT4_MSB
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 4.
ADDRESS 0XC9: USER_PATT5_LSB
ADDRESS 0XCA: USER_PATT5_MSB
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 5.
ADDRESS 0XB6: CALIBRATION STATUS
ADDRESS 0XCB: USER_PATT6_LSB
The LSB at address 0xB6 can be read to determine calibration
status. The bit is ‘0’ during calibration and goes to a logic ‘1’
when calibration is complete.This register is unique in that it can
ADDRESS 0XCC: USER_PATT6_MSB
28
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 6.
FN7911.2
April 25, 2013
ISLA224S
ADDRESS 0XCD: USER_PATT7_LSB
ADDRESS 0XCE: USER_PATT7_MSB
ADDRESS 0XE0: JESD204_CONFIG_0
Bits 7:0 “DID”, JESD204 Device ID number.
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 7.
ADDRESS 0XE1: JESD204_CONFIG_1
ADDRESS 0XCF: USER_PATT8_LSB
ADDRESS 0XE2: JESD204_CONFIG_2
ADDRESS 0XD0: USER_PATT8_MSB
Bits 4:0 “LID” JESD204 Lane ID.
These registers define the lower and upper eight bits,
respectively, of the user-defined pattern 8.
ADDRESS 0XE3: JESD204_CONFIG_3
ADDRESS 0xDF - 0xF3: JESD204 REGISTERS
Address 0xDF-0xEE: JESD204 Parameter
INTERFACE
This set of registers controls the JESD204 transmitter
configuration. By programming these parameters, the system
can select between efficient and simple packing, select the
number of powered up SERDES lanes, choose the ADC resolution
transmitted, and so on. The JESD204 parameters for standard
dual channel products are shown in Table 5. This is a small
subset of the total number of configurations supported; contact
the factory for details.
0xE0 through 0xED are the JESD204 parameter registers. These
parameters are written to set the transport layer mapping of the
JESD204 transmitter in this product family. These registers can
be written to shift between efficient and simple packing, to
enable or bypass scrambling, and to reduce the number of
powered up lanes used in the link. Each speed graded product
allows downgrading of the JESD204 link (such as reducing the
number of lanes, reducing the converter resolution, etc), but not
upgrading. These parameters are communicated on every lane
of the link during the 2nd multi-frame of the initial lane
alignment sequence, and therefore can be used by a generic
JESD204 receiver the supports the given configuration. See the
JESD204 specification for additional information on how these
registers are used in a JESD204 system, including encoding
rules.
Bits 3:0 “BID”, JESD204 Bank ID.
Bit 7 “SCR”, JESD204 SCR controls if scrambling across the
SERDES lane(s) is enabled (‘1’ means enabled).
Bits 4:0 “L”, JESD204 L is the number of SERDES lanes in the
link.
ADDRESS 0XE4: JESD204_CONFIG_4
Bits 7:0 “F”, JESD204 Number of octets per frame period.
ADDRESS 0XE5: JESD204_CONFIG_5
Bits 4:0 “K” JESD204 Number of frame periods per multi-frame
period. This product family supports the full programmable range
of K (decimal 0 through 31), although note that the JESD204
standard dictates a minimum number for this parameter that is
configuration dependent.
ADDRESS 0XE6: JESD204_CONFIG_6
Bits 7:0 “M” JESD204 Number of converters per device.
ADDRESS 0XE7: JESD204_CONFIG_7
Bits 7:6 “CS”, JESD204 CS is the number of control bits per
sample (Always ‘0’ for this product family).
Bits 4:0 “N”, JESD204 N is the converter resolution.
ADDRESS 0XE8: JESD204_CONFIG_8
Bits 7:5 "SUBCLASSV" JESDS204 Device Subclass Version
000 - Subclass 0
001 - Subclass 1 (not supported in this product family)
010- Subclass 2
ADDRESS 0XDF: JESD204_UPDATE_CONFIG_START
Bits 4:0 "N'", JESD204 total number of bits per sample.
Bit 0 update_start
ADDRESS 0XE9: JESD204_CONFIG_9
This self-resetting bit is used to indicate that some or all the
JESD204 parameters (addresses 0xE0 through 0xED) are going
to be written. Writing a ‘1’ to this bit will hold the JESD204 PLL
and transmitter in a reset state while these parameters are
written, because these parameters can affect the transmitter’s
dynamic behavior (such as modifying the PLL’s frequency
multiplication). The bit will automatically reset to a ‘0’ once a ‘1’
is written to address 0xEE Bit[0] “update_config W1TC”. The
recommended sequence for modifying the JESD204 transmitter
is numbered as follows:
Bits 7:5 "JESDV" JESDS204 Version
000 - JESD204A
001 - JESD204B
1. Write a ‘1’ to 0xDF Bit[0]
2. Write some or all modified values to 0xE0 through 0xEC
3. Write a ‘1’ to 0xEE Bit[0]. Note: 0xDF Bit[0] and 0xEE Bit[0] will
automatically be reset to a ‘0’ once configuration has been
applied to the circuitry.
29
Bits 4:0 "S", JESD204 number of samples per converter per
frame.
ADDRESS 0XEA: JESD204_CONFIG_10
Bit 7 “HD”, JESD204 HD indicates if a converter’s sample can be
split across multiple lanes in the link (always ‘0’ for this product
family).
Bits 4:0 “CF”, JESD204 CF is the number of control fames per
frame clock (always ‘0’ for this product family).
ADDRESS 0XEB: JESD204_CONFIG_11
Bits 7:0 “RES1”, JESD204 reserved for future use.
FN7911.2
April 25, 2013
ISLA224S
ADDRESS 0XEC: JESD204_CONFIG_12
ADDRESS 0XF2: JESD204_TRANS_PAT_CONFIG
Bits 7:0 “RES2”, JESD204 reserved for future use.
Bit 0 “no_mf_lane_sync”, By default, this device family assumes
that both sides of the link support lane synchronization. As per
the JESD204 rev A standard, in this case continuous frame
alignment monitoring via character substitution (section 5.3.3.4)
is modified such that a different control character is substituted
when the octet reoccurrence happens at the end of a multiframe. This behavior occurs when bit 0 is ‘0’ (the power on
default). Writing a ‘1’ to bit 0 will inform the JESD204 transmitter
than the receiving device does not support lane synchronization,
and therefore the transmitter will no longer substitute this
different control character when reoccurrence of octets occurs at
the end of a multi-frame.
ADDRESS 0XED: JESD204_CONFIG_13
Bits 7:0 “FCHK” JESD204 checksum (unsigned sum MOD 256) of
all the other JESD204 parameter register values. This is a
read-only register, as the checksum is calculated by the device.
ADDRESS 0XEE:
JESD204_UPDATE_CONFIG_COMPLETE
Bit 0 update_complete
This self-resetting bit is used to indicate that all the modifications
to the JESD204 parameters are complete.
ADDRESS 0XEF: JESD204_PLL_MONITOR_RESET
Bit 0 “pll_lock_mon_rst”, This self resetting register resets the
state of the 0xF0 Bit[0] “latched_pll_lockn” bit. The purpose of
this pair of bits is as a debugging feature to the system designer.
The “latched_pll_lockn” bit indicates if the JESD204 transmitter
PLL inside the device has at any time lost lock since the last ‘1’
was written to the “pll_lock_mon_rst” bit. This can be used to
help identify the source of intermittent link lost errors in the
system.
ADDRESS 0XF0: JESD204_STATUS
Bit 2 “op_cfg_wrong” indicates if the JESD204 parameters
(registers 0xE0 through 0xED) are supported by the JESD204
transmitter (a ‘1’ indicates they are not supported, a ‘0’ indicates
they are supported).
Bit 1“pll_lockn” indicates if the JESD204 transmitter PLL is
currently locked (a ‘1’ indicates it is not locked, a ‘0’ indicates it
is locked).
Bit 0 “latched_pll_lockn” indicates if the JESD204 transmitter
PLL has lost lock since the last assertion of the
“pll_lock_mon_rst” (see register 0xEF description for more
information).
ADDRESS 0XF1: JESD204_SYNC
Bit 0 “sync_req” this register provides a SPI-programmable
interface that can be used to assert and de-assert the JESD204
SYNC~ functionality. Certain systems may benefit from the
elimination of SYNC~ as a separate board-level LVDS signal (and
the power, PCB space, and pins it consumes), and these systems
can use this register to functionally assert and de-assert SYNC~.
For this bit to have any effect, a ‘1’ must have previously been
written to the SYNC_FUNCTION (Address 0x77, bit 0).
Bit 1 “trans_pat_max_len” There is some ambiguity of the proper
length of the JESD204 rev A section 5.1.6.2 required transport
layer test pattern. Specifically, that the description perhaps
should have “max()” in place of “min()” for the equation defining
the length of the pattern. Setting bit 1 in this register to a ‘0’ (also
the power-on default) and issuing this test pattern by writing to
0xC0 will cause the pattern to assume a “min()” interpretation of
the pattern described in section 5.1.6.2. Setting the bit to a ‘1’
will assume a “max()” interpretation of the described pattern.
ADDRESS 0XF3: JESD204_CML_POLARITY
0xF3 Bit[2:0]: “TX polarity flip lane x” This register allows the
system designer to invert the sense of the SERDES pins on a per
lane basis. For example, writing a ‘1’ to Bit[0] causes LANE0N to
functionally become LANE0P and LANE0P to become LANE0N.
This feature allows the system designer to avoid having to
crossover P and N sides of the CML pair on the board to match
pin out and layout of the transmitter and receiver. Typically, a
trace crossover would require vias, which can degrade the signal
integrity of the high-speed SERDES lanes.
ADDRESS 0XFE: OFFSET/GAIN_ADJUST_ENABLE
Bit 0 at this register must be set high to enable adjustment of
offset coarse and fine adjustments coreA (0x20 and 0x21), coreB
(0x26 and 0x27) and gain medium and gain fine adjustments
coreA (0x23 and 0x24), coreB (0x29 and 0x2A). It is
recommended that new data be written to the offset and gain
adjustment registers coreA(0x20, 0x21, 0x23, 0x24) and
coreB(0x26, 0x27, 0x29, 0x2A) while Bit 0 is a ‘0’. Subsequently,
Bit 0 should be set to ‘1’ to allow the values written to the
aforementioned registers to be used by the ADC. Bit 0 should be
set to a ‘0’ upon completion.
A ‘1’ written to this bit will result in behavior identical to the
assertion of SYNC~ (comma character generation), and ‘0’ will
result in the behavior identical to the de-assertion of SYNC~
(initial lane alignment sequence followed by converter data).
Usage of this SPI SYNC~ capability may compromise the
system’s ability to perform multi-chip time alignment, as the
SYNC~ asserted to de-asserted transition using this register is
not well timed with respect to sample clock.
30
FN7911.2
April 25, 2013
ISLA224S
Device Config/Control
DUT Info
SPI Config/Control
SPI Memory Map
ADDR.
(Hex)
PARAMETER NAME
BIT 7
(MSB)
00
port_config
01
Reserved
Reserved
02
burst_end
Burst end address [7:0]
03-07
Reserved
Reserved
08
chip_id
Chip ID #
Read only
09
chip_version
Chip Version #
Read only
0A-0F
Reserved
Reserved
10-1F
Reserved
Reserved
20
offset_coarse_coreA
Coarse Offset
cal. value
21
offset_fine_coreA
Fine Offset
cal. value
22
gain_coarse_coreA
23
gain_medium_coreA
Medium Gain
cal. value
24
gain_fine_coreA
Fine Gain
cal. value
25
modes_coreA
26
offset_coarse_coreB
Coarse Offset
cal. value
27
offset_fine_coreB
Fine Offset
cal. value
28
gain_coarse_coreB
29
gain_medium_coreB
Medium Gain
cal. value
2A
gain_fine_coreB
Fine Gain
cal. value
2B
modes_coreB
2C-6F
Reserved
Reserved
70
skew_diff
Differential Skew
71
phase_slip
72
clock_divide
BIT 6
BIT 5
BIT 4
BIT 3
SDO Active LSB First Soft Reset
Reserved
BIT 1
BIT 0
(LSB)
DEF. VALUE
(HEX)
Mirror
(bit5)
Mirror
(bit6)
Mirror
(bit7)
00h
00h
Coarse Gain
Reserved
cal. value
Power Down Mode coreA [2:0]
000 = Pin Control
001 = Normal Operation
010 = Nap
100 = Sleep
Other codes = Reserved
Reserved
Coarse Gain
Reserved
00h
NOT reset by
Soft Reset
cal. value
Power Down Mode coreB [2:0]
000 = Pin Control
001 = Normal Operation
010 = Nap
100 = Sleep
Other codes = Reserved
Reserved
31
BIT 2
00h
NOT reset by
Soft Reset
80h
Next Clock
Edge
Clock Divide [2:0]
000 = Pin Control
001 = divide by 1
010 = divide by 2
100 = divide by 4
Other codes = Reserved
00h
00h
NOT reset by
Soft Reset
FN7911.2
April 25, 2013
ISLA224S
Device Config/Control
SPI Memory Map (Continued)
ADDR.
(Hex)
PARAMETER NAME
73
output_mode_A
74
output_mode_B
75-76
Reserved
77
SYNC_function
78-B5
Reserved
B6
cal_status
B7-BF
Reserved
BIT 7
(MSB)
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
(LSB)
DEF. VALUE
(HEX)
00h
Output Format [2:0]
000 = Two’s Complement (Default) NOT reset by
Soft Reset
010 = Gray Code
100 = Offset Binary
Other codes = Reserved
00h
NOT reset by
Soft Reset
DLL Range
0 = Fast
1 = Slow
Default=’0
’
Reserved
Clkdivrst
Reserved
Reserved
32
Calibration
Done
Read Only
FN7911.2
April 25, 2013
ISLA224S
SPI Memory Map (Continued)
ADDR.
(Hex)
PARAMETER NAME
C0
test_io
BIT 7
(MSB)
BIT 6
BIT 5
BIT 4
Output Test Mode [7:4]
BIT 3
JESD Test
Device Test
<7:4>=Output Test, <3> = JESD Test
JESD Test=0
Output Test =
0x0= Output Test Mode Off. During calibration MSB
justified constant output 0xCCCC
0x1 = Midscale adjusted by numeric format
0x2 = Plus full scale, adjusted by numeric format
0x3 = Minus full scale adjusted by numeric format
0x4 = Checkboard output - 0xAAAA, 0x5555
0x5 = reserved
0x6 = reserved
0x7 = 0xFFFF, 0x0000 all on pattern
0x8 = User pattern 8 deep, MSB justified with output
0x9 = reserved
0xA, Count-up ramp
0xB, PRBS-9
0xC, PRBS-15
0xD, PRBS-23
0xE, PRBS-31
0xF = reserved
JESD Test=1
Output Test =
0x0 =Link Layer Repeat K28.5+Lane Alignment Sequence
0x1, Link Layer Repeat K28.5
0x2, Link Layer Repeat D21.5
0x3, Link Layer Repeat K28.7
0x4, Link Layer PRBS-7
0x5, Link Layer PRBS-23
0x6, Link Layer All Zeros
0x7, Link Layer All Ones
0x8-0xE, reserved
0xF, JESD204 section 5.1.6.2 Transport Layer Test Pattern
BIT 2
BIT 1
BIT 0
(LSB)
User Test Mode [2:0]
User Test Mode (Single ADC
products only)
0 = user pattern 1 only
1 = cycle pattern 1 through 2
2 = cycle pattern 1 through 3
3 = cycle pattern 1 through 4
4 = cycle pattern 1 through 5
5 = cycle pattern 1 through 6
6 = cycle pattern 1 through 7
7 = cycle pattern 1 through 8
User Test Mode (Dual and
interleaved ADC products only)
0 = cycle pattern 1 through 2
1 = cycle pattern 1 through 4
2 = cycle pattern 1 through 6
3 = cycle pattern 1 through 8
4 -7 = NA
DEF. VALUE
(HEX)
00h
C1
user_patt1_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
C2
user_patt1_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
C3
user_patt2_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
C4
user_patt2_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
C5
user_patt3_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
C6
user_patt3_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
C7
user_patt4_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
C8
user_patt4_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
C9
user_patt5_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
CA
user_patt5_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
CB
user_patt6_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
CC
user_patt6_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
CD
user_patt7_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
CE
user_patt7_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
CF
user_patt8_lsb
B7
B6
B5
B4
B3
B2
B1
B0
00h
D0
user_patt8_msb
B15
B14
B13
B12
B11
B10
B9
B8
00h
D1-DE
Reserved
Reserved
33
FN7911.2
April 25, 2013
ISLA224S
SPI Memory Map (Continued)
JESD204 Interface
ADDR.
(Hex)
PARAMETER NAME
BIT 7
(MSB)
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
(LSB)
DEF. VALUE
(HEX)
update_
start
00h
DF
JESD204_update_config_star
t
E0
JESD204_config_0
E1
JESD204_config_1
E2
JESD204_config_2
E3
JESD204_config_3
E4
JESD204_config_4
E5
JESD204_config_5
E6
JESD204_config_6
E7
JESD204_config_7
E8
JESD204_config_8
E9
JESD204_config_9
EA
JESD204_config_10
EB
JESD204_config_11
RES1
00h
EC
JESD204_config_12
RES2
00h
ED
JESD204_config_13
FCHK (Checksum)
AAh
EE
JESD204_update_config_com
plete
update_
complete
00h
EF
JESD204_PLL_monitor_reset
pll_lock_
mon_rst
00h
F0
JESD204_status
latched_
pll_lockn
00h
F1
JESD204_sync
F2
JESD204_trans_pat_config
F3
JESD204_CML_polarity
F4-FD
Reserved
FE
Offset/Gain_Adjust_Enable
FF
Reserved
DID (Device ID Number)
00h
BID (Bank ID Number)
SCR
00h
LID (Lane ID Number)
00h
L (Number of Lanes per Device)
82h
F (Number of Octets per Frame)
06h
K (Number of frames per multi-frame)
02h
M (Number of Converters per Device)
CS (Number of Control
bits per Sample)
HD
01h
N (Converter Resolution in bits)
0Dh
SUBCLASSV
N’ (Total number of bits per Sample)
0Dh
JESDV
S (Number of Samples per Converter per Frame)
05h
CF (Number of Control Words per Frame per Link)
00h
op_confg_ pll_lockn
wrong
sync_req
trans_pat_ no_mf_
max_len lane_sync
lane_2_
polarity
lane_1_
polarity
lane_0_
polarity
00h
Enable
‘1’=Enable
00h
Reserved
Reserved
For additional products, see www.intersil.com/product_tree
Intersil products are manufactured, assembled and tested utilizing ISO9000 quality systems as noted
in the quality certifications found at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time
without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be
accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
34
FN7911.2
April 25, 2013
ISLA224S
Equivalent Circuits
AVDD
AVDD
TO
CHARGE
PIPELINE
INP
600
E3
11k
CSAMP
4pF
AVDD
18k
TO
CHARGE
PIPELINE
INN
E2
E1
CLKP
AVDD
E2
E1
TO
CLOCK-PHASE
GENERATION
AVDD
CSAMP
4pF
E3
AVDD
18k
11k
CLKN
FIGURE 58. ANALOG INPUTS
AVDD
FIGURE 59. CLOCK INPUTS
AVDD
(20k PULL-UP
ON RESETN
ONLY)
AVDD
75k
AVDD
OVDD
TO
SENSE
LOGIC
75k
280
INPUT
OVDD
OVDD
20k
INPUT
75k
TO
280
75k
LOGIC
FIGURE 61. DIGITAL INPUTS
FIGURE 60. TRI-LEVEL DIGITAL INPUTS
OVDD
50
OVDD
50
LANE[2:0]P
AVDD
OVDD
VCM
LANE[2:0]N
1.0V
DATA
+
–
DATA
16mA
FIGURE 62. CML OUTPUTS
35
FIGURE 63. VCM_OUT OUTPUT
FN7911.2
April 25, 2013
ISLA224S
ADC Evaluation Platform
Intersil offers ADC Evaluation platforms which can be used to
evaluate any of Intersil’s high speed ADC products. Each platform
consists of a FPGA based data capture motherboard and a family
of ADC daughtercards. The USB interface and evaluation
platform control software allow a user to quickly evaluate the
ADC’s performance at a user’s specific application frequency
requirements. More information is available at
http://www.intersil.com/converters/adc_eval_platform/
Layout Considerations
Split Ground and Power Planes
Data converters operating at high sampling frequencies require
extra care in PC board layout. Many complex board designs
benefit from isolating the analog and digital sections. Analog
supply and ground planes should be laid out under signal and
clock inputs. Locate the digital planes under outputs and logic
pins. Grounds should be joined under the chip.
Clock Input Considerations
Use matched transmission lines to the transformer inputs for the
analog input and clock signals. Locate transformers and
terminations as close to the chip as possible.
Exposed Paddle
The exposed paddle must be electrically connected to analog
ground (AVSS) and should be connected to a large copper plane
using numerous vias for optimal thermal performance.
Bypass and Filtering
Bulk capacitors should have low equivalent series resistance.
Tantalum is a good choice. For best performance, keep ceramic
bypass capacitors very close to device pins, as longer traces
between the ceramic bypass capacitors and the device pins will
increase inductance, which can result in diminished dynamic
performance. Best practices bypassing is especially important on
the AVDD and OVDD(PLL) power supply pins. Whenever possible,
each supply pin should have its own 0.1uF bypass capacitor.
Make sure that connections to ground are direct and low
impedance. Avoid forming ground loops.
CML Outputs
Output traces and connections must be designed for 50Ω (100Ω
differential) characteristic impedance. Keep traces direct and
short, and minimize bends and vias where possible. Avoid
crossing ground and power-plane breaks with signal traces. Keep
good clearance (at least 5 trace widths) between the SERDES
traces and other signals. Given the speed of these outputs and
importance of maintaining an open eye to achieve low BER,
signal integrity simulations are recommended, especially when
the data lane rate exceeds 3Gbps and/or the trace or cable
length between the ADC and the reciever gets larger than 20cm.
Unused Inputs
Standard logic inputs (RESETN, CSB, SCLK, SDIO, SDO) which will
not be operated do not require connection to ensure optimal ADC
performance. These inputs can be left floating if they are not
36
used. Tri-level inputs (NAPSLP) accept a floating input as a valid
state, and therefore should be biased according to the desired
functionality.
Definitions
Analog Input Bandwidth is the analog input frequency at which the
spectral output power at the fundamental frequency (as determined
by FFT analysis) is reduced by 3dB from its full-scale low-frequency
value. This is also referred to as Full Power Bandwidth.
Aperture Delay or Sampling Delay is the time required after the
rise of the clock input for the sampling switch to open, at which
time the signal is held for conversion.
Aperture Jitter is the RMS variation in aperture delay for a set of
samples.
Clock Duty Cycle is the ratio of the time the clock wave is at logic
high to the total time of one clock period.
Differential Non-Linearity (DNL) is the deviation of any code width
from an ideal 1 LSB step.
Effective Number of Bits (ENOB) is an alternate method of
specifying Signal to Noise-and-Distortion Ratio (SINAD). In dB, it
is calculated as: ENOB = (SINAD - 1.76)/6.02
Gain Error is the ratio of the difference between the voltages that
cause the lowest and highest code transitions to the full-scale
voltage less than 2 LSB. It is typically expressed in percent.
I2E The Intersil Interleave Engine. This highly configurable
circuitry performs estimates of offset, gain, and sample time
skew mismatches between the core converters, and updates
analog adjustments for each to minimize interleave spurs.
Integral Non-Linearity (INL) is the maximum deviation of the
ADC’s transfer function from a best fit line determined by a least
squares curve fit of that transfer function, measured in units of
LSBs.
Least Significant Bit (LSB) is the bit that has the smallest value or
weight in a digital word. Its value in terms of input voltage is
VFS/(2N - 1) where N is the resolution in bits.
Missing Codes are output codes that are skipped and will never
appear at the ADC output. These codes cannot be reached with
any input value.
Most Significant Bit (MSB) is the bit that has the largest value or
weight.
Pipeline Delay is the number of clock cycles between the
initiation of a conversion and the appearance at the output pins
of the data.
Power Supply Rejection Ratio (PSRR) is the ratio of the observed
magnitude of a spur in the ADC FFT, caused by an AC signal
superimposed on the power supply voltage.
Signal to Noise-and-Distortion (SINAD) is the ratio of the RMS
signal amplitude to the RMS sum of all other spectral
components below one half the clock frequency, including
harmonics but excluding DC.
FN7911.2
April 25, 2013
ISLA224S
Signal-to-Noise Ratio (without Harmonics) is the ratio of the RMS
signal amplitude to the RMS sum of all other spectral
components below one-half the sampling frequency, excluding
harmonics and DC.
Spurious-Free-Dynamic Range (SFDR) is the ratio of the RMS
signal amplitude to the RMS value of the largest spurious
spectral component. The largest spurious spectral component
may or may not be a harmonic.
SNR and SINAD are either given in units of dB when the power of
the fundamental is used as the reference, or dBFS (dB to full
scale) when the converter’s full-scale input power is used as the
reference.
Revision History
The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to web to make sure you
have the latest Rev.
DATE
REVISION
CHANGE
April 16, 2013
FN7911.2 Page 29, 34: Updated JESD204_config register definitions for E8, E9
Page 34: Added default values for JESD204_config registers
April 17, 2012
FN7911.1 Release of 125MSPS Grade;
Page 1 - Key Specifications Changes
Showing SNR/SFDR page 1 bullets at 30MHz and 190MHz (was 30MHz and 363MHz)
Pin-Compatible Family Updated by removing Model ISLA224S17
Page 3 - Updated Ordering Information Table by removing part ISLA224S17IR1Z, removing "coming soon" from Part
ISLA224S12IR1Z and adding Eval board "ISLA224S25IR48EV1Z"
Page 5 - Updated Electrical Specs as follows:
Added MIN and Max values to ISLA224S12 Full-Scale Analog Input Range,
Input Offset Voltage, 1.8V Analog and Digital Supply Voltage and added MAX values to
1.8 Analog and Digital Supply Current
Page 6 to Page 7
Added Max values to ISLA224S12 Total Power Dissipation Normal Mode, Nap Mode and Sleep Mode
Added MIN and Max values to ISLA224S12 Differential Nonlinearity and changed TYP from ±0.3 to ±0.18
Changed TYP in Integral Nonlinearity from ±2.3 to ±2.0
Added Conditions to Minimum Conversion Rate and added Typical value to ISLA224S12
Added Minimum and Maximum Serdes Lane Data Rate specs
Added MIN values for ISLA224S12 fin = 105MHz for Signal to Noise Ratio, Signal to Noise and Distortion, Effective
Number of Bits and Spurious-Free Dynamic Range
Page 10 - Typical Performance Curves Changes
Added to Figure 9 - Power vs fSample 2 Lanes and Efficient Packing
Added Differential and Integral Nonlinearity, Noise Histogram and Single tone spectrum graphics for 125 MBPS
Page 23 - Updated JESD204 CONFIGURATIONS AND CLOCK FREQUENCIES Table
Page 22 - Rewrote Lane Data Rate section
Page 23 - Updated JES204 Parameters Table by removing Product column
Page 26 - Updated table heads for Tables 7, 8 and 9
Page 31 - Updated SPI Memory Map
December 20, 2011 FN7911.0 Initial Release
About Intersil
Intersil Corporation is a leader in the design and manufacture of high-performance analog, mixed-signal and power management
semiconductors. The company's products address some of the largest markets within the industrial and infrastructure, personal
computing and high-end consumer markets. For more information about Intersil, visit our website at www.intersil.com.
For the most updated datasheet, application notes, related documentation and related parts, please see the respective product
information page found at www.intersil.com. You may report errors or suggestions for improving this datasheet by visiting
www.intersil.com/en/support/ask-an-expert.html. Reliability reports are also available from our website at
http://www.intersil.com/en/support/qualandreliability.html#reliability
37
FN7911.2
April 25, 2013
ISLA224S
Package Outline Drawing
L48.7x7G
48 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE
Rev 0, 1/10
7.00
6
6
PIN #1
INDEX
AREA
4X 5.5
A
B
37
PIN 1
INDEX AREA
48
36
1
7.00
44X 0.50
(4X)
EXP. DAP
5.70 SQ.
12
25
0.15
24
13
48X 0.40
48x 0.20 4
TOP VIEW
BOTTOM VIEW
SEE DETAIL "X"
1.00 MAX
0.10 C
C
0.08 C
SEATING PLANE
( 44X 0 . 5 )
6 .80 SQ
SIDE VIEW
5.70 SQ
C
0 . 2 REF
5
( 48X 0 . 20 )
0 . 00 MIN.
0 . 05 MAX.
( 48X 0 . 60 )
TYPICAL RECOMMENDED LAND PATTERN
DETAIL "X"
NOTES:
1.
Dimensions are in millimeters.
Dimensions in ( ) for Reference Only.
2.
Dimensioning and tolerancing conform to ASME Y14.5m-1994.
3.
Unless otherwise specified, tolerance : Decimal ± 0.05
4.
Dimension applies to the metallized terminal and is measured
between 0.015mm and 0.30mm from the terminal tip.
5.
Tiebar shown (if present) is a non-functional feature.
6.
The configuration of the pin #1 identifier is optional, but must be
located within the zone indicated. The pin #1 indentifier may be
either a mold or mark feature.
38
FN7911.2
April 25, 2013
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