AD AD9627 1.8 v dual analog-to-digital converter Datasheet

12-Bit, 80 MSPS/105 MSPS/125 MSPS/150 MSPS,
1.8 V Dual Analog-to-Digital Converter
AD9627
FUNCTIONAL BLOCK DIAGRAM
AVDD DVDD
SDIO/ SCLK/
DCS DFS CSB
FD(0:3)A
FD BITS/THRESHOLD
DETECT
DRVDD
SPI
PROGRAMMING DATA
VIN+A
SHA
ADC
VIN–A
SIGNAL
MONITOR
VREF
D11A
D0A
CLK+
CLK–
CML
DIVIDE
1 TO 8
REF
SELECT
DCO
GENERATION
DUTY CYCLE
STABILIZER
RBIAS
VIN–B
SHA
ADC
VIN+B
SIGNAL MONITOR
DATA
AD9627
MULTICHIP
SYNC
AGND
SYNC
FD BITS/THRESHOLD
DETECT
FD(0:3)B
DCOA
DCOB
D11B
D0B
SIGNAL MONITOR
INTERFACE
SMI
SMI
SMI DRGND
SDFS SCLK/ SDO/
PDWN OEB
NOTES
1. PIN NAMES ARE FOR THE CMOS PIN CONFIGURATION ONLY;
SEE FIGURE 7 FOR LVDS PIN NAMES.
06571-001
SENSE
CMOS
OUTPUT BUFFER
SNR = 69.4 dBc (70.4 dBFS) to 70 MHz @ 125 MSPS
SFDR = 85 dBc to 70 MHz @ 125 MSPS
Low power: 750 mW @ 125 MSPS
SNR = 69.2 dBc (70.2 dBFS) to 70 MHz @ 150 MSPS
SFDR = 84 dBc to 70 MHz @ 150 MSPS
Low power: 820 mW @ 150 MSPS
1.8 V analog supply operation
1.8 V to 3.3 V CMOS output supply or 1.8 V LVDS
output supply
Integer 1-to-8 input clock divider
IF sampling frequencies to 450 MHz
Internal ADC voltage reference
Integrated ADC sample-and-hold inputs
Flexible analog input range: 1 V p-p to 2 V p-p
Differential analog inputs with 650 MHz bandwidth
ADC clock duty cycle stabilizer
95 dB channel isolation/crosstalk
Serial port control
User-configurable, built-in self-test (BIST) capability
Energy-saving power-down modes
Integrated receive features
Fast detect/threshold bits
Composite signal monitor
CMOS
OUTPUT BUFFER
FEATURES
Figure 1.
APPLICATIONS
Communications
Diversity radio systems
Multimode digital receivers (3G)
GSM, EDGE, WCDMA,
CDMA2000, WiMAX, TD-SCDMA
I/Q demodulation systems
Smart antenna systems
General-purpose software radios
Broadband data applications
PRODUCT HIGHLIGHTS
1.
2.
3.
4.
5.
6.
7.
Integrated dual, 12-bit, 80 MSPS/105 MSPS/125 MSPS/
150 MSPS ADC.
Fast overrange detect and signal monitor with serial output.
Signal monitor block with dedicated serial output mode.
Proprietary differential input that maintains excellent SNR
performance for input frequencies up to 450 MHz.
Operation from a single 1.8 V supply and a separate digital
output driver supply to accommodate 1.8 V to 3.3 V logic
families.
Standard serial port interface (SPI) that supports various
product features and functions, such as data formatting
(offset binary, twos complement, or gray coding), enabling
the clock DCS, power-down, test modes, and voltage
reference mode.
Pin compatibility with the AD9640, AD9627-11, and AD9600
for a simple migration from 12 bits to 14 bits, 11 bits, or
10 bits.
Rev. B
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AD9627* PRODUCT PAGE QUICK LINKS
Last Content Update: 02/23/2017
COMPARABLE PARTS
TOOLS AND SIMULATIONS
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• Visual Analog
• AD9627 IBIS Models
EVALUATION KITS
• AD9627/AD9640 S-Parameters
• AD9627 Evaluation Board
REFERENCE MATERIALS
DOCUMENTATION
Technical Articles
Application Notes
• MS-2210: Designing Power Supplies for High Speed ADC
• AN-1142: Techniques for High Speed ADC PCB Layout
• AN-282: Fundamentals of Sampled Data Systems
DESIGN RESOURCES
• AN-345: Grounding for Low-and-High-Frequency Circuits
• AD9627 Material Declaration
• AN-715: A First Approach to IBIS Models: What They Are
and How They Are Generated
• PCN-PDN Information
• AN-737: How ADIsimADC Models an ADC
• Symbols and Footprints
• AN-742: Frequency Domain Response of SwitchedCapacitor ADCs
• AN-756: Sampled Systems and the Effects of Clock Phase
Noise and Jitter
• AN-807: Multicarrier WCDMA Feasibility
• AN-808: Multicarrier CDMA2000 Feasibility
• AN-812: MicroController-Based Serial Port Interface (SPI)
Boot Circuit
• AN-827: A Resonant Approach to Interfacing Amplifiers to
Switched-Capacitor ADCs
• AN-835: Understanding High Speed ADC Testing and
Evaluation
• AN-851: A WiMax Double Downconversion IF Sampling
Receiver Design
• Quality And Reliability
DISCUSSIONS
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SAMPLE AND BUY
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TECHNICAL SUPPORT
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number.
DOCUMENT FEEDBACK
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• AN-878: High Speed ADC SPI Control Software
• AN-905: Visual Analog Converter Evaluation Tool Version
1.0 User Manual
• AN-935: Designing an ADC Transformer-Coupled Front
End
Data Sheet
• AD9627: 12-Bit, 80 MSPS/105 MSPS/125 MSPS/150 MSPS,
1.8 V Dual Analog-to-Digital Converter Data Sheet
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AD9627
TABLE OF CONTENTS
Features .............................................................................................. 1
Signal Monitor ................................................................................ 36
Applications ....................................................................................... 1
Peak Detector Mode................................................................... 36
Functional Block Diagram .............................................................. 1
RMS/MS Magnitude Mode ......................................................... 36
Product Highlights ........................................................................... 1
Threshold Crossing Mode ......................................................... 37
Revision History ............................................................................... 3
Additional Control Bits ............................................................. 37
General Description ......................................................................... 4
DC Correction ............................................................................ 37
Specifications..................................................................................... 5
Signal Monitor SPORT Output ................................................ 38
ADC DC Specifications—AD9627-80/AD9627-105 .................. 5
Built-In Self-Test (BIST) and Output Test .................................. 39
ADC DC Specifications—AD9627-125/AD9627-150 ................ 6
Built-In Self-Test (BIST) ............................................................ 39
ADC AC Specifications—AD9627-80/AD9627-105................... 7
Output Test Modes ..................................................................... 39
ADC AC Specifications—AD9627-125/AD9627-150................. 8
Channel/Chip Synchronization .................................................... 40
Digital Specifications ................................................................... 9
Serial Port Interface (SPI) .............................................................. 41
Switching Specifications—AD9627-80/AD9627-105................ 11
Configuration Using the SPI ..................................................... 41
Switching Specifications—AD9627-125/AD9627-150.............. 12
Hardware Interface..................................................................... 41
Timing Specifications ................................................................ 13
Configuration Without the SPI ................................................ 42
Absolute Maximum Ratings.......................................................... 15
SPI Accessible Features .............................................................. 42
Thermal Characteristics ............................................................ 15
Memory Map .................................................................................. 43
ESD Caution ................................................................................ 15
Reading the Memory Map Register Table............................... 43
Pin Configurations and Function Descriptions ......................... 16
Memory Map Register Table ..................................................... 44
Equivalent Circuits ......................................................................... 20
Memory Map Register Descriptions ........................................ 47
Typical Performance Characteristics ........................................... 21
Applications Information .............................................................. 50
Theory of Operation ...................................................................... 26
Design Guidelines ...................................................................... 50
ADC Architecture ...................................................................... 26
Evaluation Board ............................................................................ 51
Analog Input Considerations.................................................... 26
Power Supplies ............................................................................ 51
Voltage Reference ....................................................................... 28
Input Signals................................................................................ 51
Clock Input Considerations ...................................................... 29
Output Signals ............................................................................ 51
Power Dissipation and Standby Mode ..................................... 31
Default Operation and Jumper Selection Settings ................. 52
Digital Outputs ........................................................................... 32
Alternative Clock Configurations ............................................ 52
Timing .......................................................................................... 32
Alternative Analog Input Drive Configuration...................... 53
ADC Overrange and Gain Control .............................................. 33
Schematics ................................................................................... 54
Fast Detect Overview ................................................................. 33
Evaluation Board Layouts ......................................................... 64
ADC Fast Magnitude ................................................................. 33
Bill of Materials ........................................................................... 72
ADC Overrange (OR) ................................................................ 34
Outline Dimensions ....................................................................... 74
Gain Switching ............................................................................ 34
Ordering Guide .......................................................................... 74
Rev. B | Page 2 of 76
AD9627
REVISION HISTORY
5/10—Rev. A to Rev. B
Deleted CP-64-3 Package .................................................. Universal
Added CP-64-6 Package .................................................... Universal
Changed AD9627BCPZ-80 to AD9267-80 and
AD9627BCPZ-105 to AD9627-105 Throughout.......................... 5
Changed AD9627BCPZ-125 to AD9267-125 and
AD9627BCPZ-150 to AD9627-150 Throughout.......................... 6
Changes to Figure 6.........................................................................16
Changes to Figure 7.........................................................................18
Updated Outline Dimensions ........................................................74
Changes to Ordering Guide ...........................................................74
6/09—Rev. 0 to Rev. A
Changes to Table 6 ..........................................................................11
Changes to Table 7 ..........................................................................12
Changes to Figure 3.........................................................................14
Changes to Figure 11, Figure 12, and Figure 14 ..........................20
Changes to Table 15 ........................................................................32
Changes to Configuration Using the SPI Section .......................41
Change to Table 25 ..........................................................................46
Change to Signal Monitor Period (Register 0x113
to Register 0x115) Section..............................................................49
Updated Outline Dimensions ........................................................74
10/07—Revision 0: Initial Version
Rev. B | Page 3 of 76
AD9627
GENERAL DESCRIPTION
The AD9627 is a dual, 12-bit, 80 MSPS/105 MSPS/125 MSPS/
150 MSPS analog-to-digital converter (ADC). The AD9627 is
designed to support communications applications where low
cost, small size, and versatility are desired.
exceeds the programmable threshold, the coarse upper threshold
indicator goes high. Because this threshold indicator has very
low latency, the user can quickly turn down the system gain to
avoid an overrange condition.
The dual ADC core features a multistage, differential pipelined
architecture with integrated output error correction logic. Each
ADC features wide bandwidth differential sample-and-hold
analog input amplifiers supporting a variety of user-selectable
input ranges. An integrated voltage reference eases design considerations. A duty cycle stabilizer is provided to compensate for
variations in the ADC clock duty cycle, allowing the converters
to maintain excellent performance.
The second AGC-related function is the signal monitor. This block
allows the user to monitor the composite magnitude of the
incoming signal, which aids in setting the gain to optimize the
dynamic range of the overall system.
The AD9627 has several functions that simplify the automatic
gain control (AGC) function in the system receiver. The fast detect
feature allows fast overrange detection by outputting four bits of
input level information with very short latency.
In addition, the programmable threshold detector allows monitoring of the incoming signal power, using the four fast detect
bits of the ADC with very low latency. If the input signal level
The ADC output data can be routed directly to the two external
12-bit output ports. These outputs can be set from 1.8 V to 3.3 V
CMOS or 1.8 V LVDS.
Flexible power-down options allow significant power savings,
when desired.
Programming for setup and control is accomplished using a 3-bit
SPI-compatible serial interface.
The AD9627 is available in a 64-lead LFCSP and is specified over
the industrial temperature range of −40°C to +85°C.
Rev. B | Page 4 of 76
AD9627
SPECIFICATIONS
ADC DC SPECIFICATIONS—AD9627-80/AD9627-105
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, maximum sample rate, VIN = −1.0 dBFS differential input, 1.0 V internal reference, DCS
enabled, fast detect output pins disabled, and signal monitor disabled, unless otherwise noted.
Table 1.
Parameter
RESOLUTION
ACCURACY
No Missing Codes
Offset Error
Gain Error
Differential Nonlinearity (DNL)1
Integral Nonlinearity (INL)1
MATCHING CHARACTERISTIC
Offset Error
Gain Error
TEMPERATURE DRIFT
Offset Error
Gain Error
INTERNAL VOLTAGE REFERENCE
Output Voltage Error (1 V Mode)
Load Regulation @ 1.0 mA
INPUT REFERRED NOISE
VREF = 1.0 V
ANALOG INPUT
Input Span, VREF = 1.0 V
Input Capacitance2
VREF INPUT RESISTANCE
POWER SUPPLIES
Supply Voltage
AVDD, DVDD
DRVDD (CMOS Mode)
DRVDD (LVDS Mode)
Supply Current
IAVDD1, 3
IDVDD1, 3
IDRVDD1 (3.3 V CMOS)
IDRVDD1 (1.8 V CMOS)
IDRVDD1 (1.8 V LVDS)
POWER CONSUMPTION
DC Input
Sine Wave Input1 (DRVDD = 1.8 V)
Sine Wave Input1 (DRVDD = 3.3 V)
Standby Power4
Power-Down Power
Temperature
Full
Full
Full
Full
Full
25°C
Full
25°C
AD9627-80
Typ
Max
Min
12
+0.1
Guaranteed
±0.2
±0.6
−1.8
−3.7
±0.4
±0.2
±0.9
±0.4
Min
12
−0.5
Unit
Bits
Guaranteed
±0.3
±0.7
−2.2
−3.7
±0.4
±0.2
±0.9
±0.4
% FSR
% FSR
LSB
LSB
LSB
LSB
±0.3
±0.2
% FSR
% FSR
Full
Full
±0.2
±0.2
Full
Full
±15
±95
Full
Full
±5
7
25°C
0.3
0.3
LSB rms
Full
Full
Full
2
8
6
2
8
6
V p-p
pF
kΩ
Full
Full
Full
1.7
1.7
1.7
1.8
3.3
1.8
Full
Full
Full
Full
Full
233
26
23
11
47
Full
Full
Full
Full
Full
452
495
550
52
2.5
1
±0.6
±0.75
AD9627-105
Typ
Max
±0.7
±0.75
±15
±95
±16
1.9
3.6
1.9
278
490
6
±5
7
1.7
1.7
1.7
1.8
3.3
1.8
310
34
34
15
47
600
657
740
68
2.5
ppm/°C
ppm/°C
±16
1.9
3.6
1.9
365
650
6
mV
mV
V
V
V
mA
mA
mA
mA
mA
mW
mW
mW
mW
mW
Measured with a low input frequency, full-scale sine wave, with approximately 5 pF loading on each output bit.
Input capacitance refers to the effective capacitance between one differential input pin and AGND. See Figure 8 for the equivalent analog input structure.
3
The maximum limit applies to the combination of IAVDD and IDVDD currents.
4
Standby power is measured with a dc input and with the CLK pins inactive (set to AVDD or AGND).
2
Rev. B | Page 5 of 76
AD9627
ADC DC SPECIFICATIONS—AD9627-125/AD9627-150
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, maximum sample rate, VIN = −1.0 dBFS differential input, 1.0 V internal reference, DCS
enabled, fast detect output pins disabled, and signal monitor disabled, unless otherwise noted.
Table 2.
Parameter
RESOLUTION
ACCURACY
No Missing Codes
Offset Error
Gain Error
Differential Nonlinearity (DNL)1
Integral Nonlinearity (INL)
1
MATCHING CHARACTERISTIC
Offset Error
Gain Error
TEMPERATURE DRIFT
Offset Error
Gain Error
INTERNAL VOLTAGE REFERENCE
Output Voltage Error (1 V Mode)
Load Regulation @ 1.0 mA
INPUT REFERRED NOISE
VREF = 1.0 V
ANALOG INPUT
Input Span, VREF = 1.0 V
Input Capacitance2
VREF INPUT RESISTANCE
POWER SUPPLIES
Supply Voltage
AVDD, DVDD
DRVDD (CMOS Mode)
DRVDD (LVDS Mode)
Supply Current
IAVDD1, 3
IDVDD1, 3
IDRVDD1 (3.3 V CMOS)
IDRVDD1 (1.8 V CMOS)
IDRVDD1 (1.8 V LVDS)
POWER CONSUMPTION
DC Input
Sine Wave Input1 (DRVDD = 1.8 V)
Sine Wave Input1 (DRVDD = 3.3 V)
Standby Power4
Power-Down Power
Temperature
Full
Full
Full
Full
Full
25°C
Full
25°C
Min
12
−0.7
AD9627-125
Typ
Max
Guaranteed
±0.3
−2.7
±0.6
−3.9
±0.4
Min
12
−0.9
±0.2
AD9627-150
Typ
Max
Guaranteed
±0.2
−3.2
±0.6
−5.2
±0.9
±0.2
±0.9
±1.3
±0.4
±0.5
±0.3
±0.1
Full
Full
±15
±95
Full
Full
±5
7
25°C
0.3
0.3
LSB rms
Full
Full
Full
2
8
6
2
8
6
V p-p
pF
kΩ
1.7
1.7
1.7
1.8
3.3
1.8
Full
Full
Full
Full
Full
385
42
36
18
48
Full
Full
Full
Full
Full
750
814
900
77
2.5
1
±0.2
±0.2
±0.7
±0.8
% FSR
% FSR
LSB
LSB
LSB
LSB
25°C
25°C
Full
Full
Full
±0.6
±0.75
Unit
Bits
±15
±95
±16
1.9
3.6
1.9
455
800
6
±5
7
1.7
1.7
1.7
1.8
3.3
1.8
419
50
42
22
49
820
895
995
77
2.5
ppm/°C
ppm/°C
±16
1.9
3.6
1.9
495
890
6
Measured with a low input frequency, full-scale sine wave, with approximately 5 pF loading on each output bit.
Input capacitance refers to the effective capacitance between one differential input pin and AGND. See Figure 8 for the equivalent analog input structure.
The maximum limit applies to the combination of IAVDD and IDVDD currents.
4
Standby power is measured with a dc input and with the CLK pins inactive (set to AVDD or AGND).
2
3
Rev. B | Page 6 of 76
% FSR
% FSR
mV
mV
V
V
V
mA
mA
mA
mA
mA
mW
mW
mW
mW
mW
AD9627
ADC AC SPECIFICATIONS—AD9627-80/AD9627-105
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, maximum sample rate, VIN = −1.0 dBFS differential input, 1.0 V internal reference, DCS
enabled, fast detect output pins disabled, and signal monitor disabled, unless otherwise noted.
Table 3.
Parameter1
SIGNAL-TO-NOISE RATIO (SNR)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
SIGNAL-TO-NOISE AND DISTORTION (SINAD)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
EFFECTIVE NUMBER OF BITS (ENOB)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
WORST SECOND OR THIRD HARMONIC
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
SPURIOUS-FREE DYNAMIC RANGE (SFDR)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
WORST OTHER HARMONIC OR SPUR
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
TWO-TONE SFDR
fIN = 29.1 MHz, 32.1 MHz (−7 dBFS )
fIN = 169.1 MHz, 172.1 MHz (−7 dBFS )
CROSSTALK2
ANALOG INPUT BANDWIDTH
1
2
Temperature
25°C
25°C
Full
25°C
25°C
25°C
25°C
Full
25°C
25°C
Min
AD9627-80
Typ
Max
Min
69.7
69.5
AD9627-105
Typ
Max
69.6
69.4
68.1
dB
dB
dB
dB
dB
68.6
69.2
68.5
69.1
68.4
69.6
69.4
69.5
69.3
Unit
69.0
68.3
69.0
68.1
dB
dB
dB
dB
dB
25°C
25°C
25°C
25°C
11.5
11.4
11.4
11.3
11.4
11.4
11.4
11.2
Bits
Bits
Bits
Bits
25°C
25°C
Full
25°C
25°C
−87
−85
−87
−85
−84
−83
−84
−83
dBc
dBc
dBc
dBc
dBc
25°C
25°C
Full
25°C
25°C
87
85
87
85
67.4
68.0
−74
74
−74
dBc
dBc
dBc
dBc
dBc
74
84
83
84
83
25°C
25°C
Full
25°C
25°C
−92
−89
−92
−88
−89
−89
−87
−86
dBc
dBc
dBc
dBc
dBc
25°C
25°C
Full
25°C
85
82
−95
650
85
82
−95
650
dBc
dBc
dB
MHz
−82
See Application Note AN-835, Understanding High Speed ADC Testing and Evaluation, for a complete set of definitions.
Crosstalk is measured at 100 MHz with −1 dBFS on one channel and with no input on the alternate channel.
Rev. B | Page 7 of 76
−82
AD9627
ADC AC SPECIFICATIONS—AD9627-125/AD9627-150
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, maximum sample rate, VIN = −1.0 dBFS differential input, 1.0 V internal reference, DCS
enabled, fast detect output pins disabled, and signal monitor disabled, unless otherwise noted.
Table 4.
Parameter1
SIGNAL-TO-NOISE RATIO (SNR)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
SIGNAL-TO-NOISE AND DISTORTION (SINAD)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
EFFECTIVE NUMBER OF BITS (ENOB)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
WORST SECOND OR THIRD HARMONIC
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
SPURIOUS-FREE DYNAMIC RANGE (SFDR)
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
WORST OTHER HARMONIC OR SPUR
fIN = 2.3 MHz
fIN = 70 MHz
fIN = 140 MHz
fIN = 220 MHz
TWO-TONE SFDR
fIN = 29.1 MHz, 32.1 MHz (−7 dBFS )
fIN = 169.1 MHz, 172.1 MHz (−7 dBFS )
CROSSTALK2
ANALOG INPUT BANDWIDTH
1
2
Temperature
25°C
25°C
Full
25°C
25°C
25°C
25°C
Full
25°C
25°C
Min
AD9627-125
Typ
Max
Min
69.5
69.4
AD9627-150
Typ
Max
69.4
69.2
68.1
dB
dB
dB
dB
dB
67.1
69.1
68.8
68.8
68.2
69.4
69.3
69.3
69.1
Unit
69.0
68.3
68.7
67.8
dB
dB
dB
dB
dB
25°C
25°C
25°C
25°C
11.4
11.4
11.3
11.3
11.4
11.4
11.3
11.2
Bits
Bits
Bits
Bits
25°C
25°C
Full
25°C
25°C
−86.5
−85
−86.5
−84
−84
−83
−83.5
−77
dBc
dBc
dBc
dBc
dBc
25°C
25°C
Full
25°C
25°C
86.5
85
86.5
84
67.9
65.9
−74
74
−73
dBc
dBc
dBc
dBc
dBc
73
84
83
83.5
77
25°C
25°C
Full
25°C
25°C
−92
−89
−92
−88
−89
−89
−88
−88
dBc
dBc
dBc
dBc
dBc
25°C
25°C
Full
25°C
85
82
−95
650
85
82
−95
650
dBc
dBc
dB
MHz
−81
See Application Note AN-835, Understanding High Speed ADC Testing and Evaluation, for a complete set of definitions.
Crosstalk is measured at 100 MHz with −1 dBFS on one channel and with no input on the alternate channel.
Rev. B | Page 8 of 76
−80
AD9627
DIGITAL SPECIFICATIONS
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, maximum sample rate, VIN = −1.0 dBFS differential input, 1.0 V internal reference, and DCS
enabled, unless otherwise noted.
Table 5.
Parameter
DIFFERENTIAL CLOCK INPUTS (CLK+, CLK−)
Logic Compliance
Internal Common-Mode Bias
Differential Input Voltage
Input Voltage Range
Input Common-Mode Range
High Level Input Voltage
Low Level Input Voltage
High Level Input Current
Low Level Input Current
Input Capacitance
Input Resistance
SYNC INPUT
Logic Compliance
Internal Bias
Input Voltage Range
High Level Input Voltage
Low Level Input Voltage
High Level Input Current
Low Level Input Current
Input Capacitance
Input Resistance
LOGIC INPUT (CSB)1
High Level Input Voltage
Low Level Input Voltage
High Level Input Current
Low Level Input Current
Input Resistance
Input Capacitance
LOGIC INPUT (SCLK/DFS)2
High Level Input Voltage
Low Level Input Voltage
High Level Input Current (VIN = 3.3 V)
Low Level Input Current
Input Resistance
Input Capacitance
LOGIC INPUTS/OUTPUTS (SDIO/DCS, SMI SDFS)1
High Level Input Voltage
Low Level Input Voltage
High Level Input Current
Low Level Input Current
Input Resistance
Input Capacitance
LOGIC INPUTS/OUTPUTS (SMI SDO/OEB, SMI SCLK/PDWN)2
High Level Input Voltage
Low Level Input Voltage
High Level Input Current (VIN = 3.3 V)
Low Level Input Current
Temperature
Min
Full
Full
Full
Full
Full
Full
Full
Full
Full
Full
CMOS/LVDS/LVPECL
1.2
0.2
6
GND − 0.3
AVDD + 1.6
1.1
AVDD
1.2
3.6
0
0.8
−10
+10
−10
+10
4
8
10
12
Full
Full
Full
Full
Full
Full
Full
Full
Max
CMOS
1.2
GND − 0.3
1.2
0
−10
−10
8
Full
Full
Full
Full
Full
Full
1.22
0
−10
40
Full
Full
Full
Full
Full
Full
1.22
0
−92
−10
Full
Full
Full
Full
Full
Full
1.22
0
−10
38
Full
Full
Full
Full
1.22
0
−90
−10
Rev. B | Page 9 of 76
Typ
AVDD + 1.6
3.6
0.8
+10
+10
4
10
12
Unit
V
V p-p
V
V
V
V
μA
μA
pF
kΩ
V
V
V
V
μA
μA
pF
kΩ
3.6
0.6
+10
132
V
V
μA
μA
kΩ
pF
3.6
0.6
−135
+10
V
V
μA
μA
kΩ
pF
3.6
0.6
+10
128
V
V
μA
μA
kΩ
pF
3.6
0.6
−134
+10
V
V
μA
μA
26
2
26
2
26
5
AD9627
Parameter
Input Resistance
Input Capacitance
DIGITAL OUTPUTS
CMOS Mode—DRVDD = 3.3 V
High Level Output Voltage
IOH = 50 μA
IOH = 0.5 mA
Low Level Output Voltage
IOL = 1.6 mA
IOL = 50 μA
CMOS Mode—DRVDD = 1.8 V
High Level Output Voltage
IOH = 50 μA
IOH = 0.5 mA
Low Level Output Voltage
IOL = 1.6 mA
IOL = 50 μA
LVDS Mode—DRVDD = 1.8 V
Differential Output Voltage (VOD), ANSI Mode
Output Offset Voltage (VOS), ANSI Mode
Differential Output Voltage (VOD), Reduced Swing Mode
Output Offset Voltage (VOS), Reduced Swing Mode
1
2
Temperature
Full
Full
Min
Full
Full
3.29
3.25
Typ
26
5
0.2
0.05
1.79
1.75
Pull up.
Pull down.
Rev. B | Page 10 of 76
250
1.15
150
1.15
V
V
V
V
Full
Full
Full
Full
Full
Full
Unit
kΩ
pF
V
V
Full
Full
Full
Full
Max
350
1.25
200
1.25
0.2
0.05
V
V
450
1.35
280
1.35
mV
V
mV
V
AD9627
SWITCHING SPECIFICATIONS—AD9627-80/AD9627-105
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, maximum sample rate, VIN = −1.0 dBFS differential input, 1.0 V internal reference, and
DCS enabled, unless otherwise noted.
Table 6.
Parameter
CLOCK INPUT PARAMETERS
Input Clock Rate
Conversion Rate
DCS Enabled1
DCS Disabled1
CLK Period—Divide-by-1 Mode (tCLK)
CLK Pulse Width High
Divide-by-1 Mode, DCS Enabled
Divide by-1-Mode, DCS Disabled
Divide-by-2 Mode, DCS Enabled
Divide-by-3 Through Divide-by-8
Modes, DCS Enabled
DATA OUTPUT PARAMETERS (DATA, FD)
CMOS Mode—DRVDD = 3.3 V
Data Propagation Delay (tPD)2
DCO Propagation Delay (tDCO)
Setup Time (tS)
Hold Time (tH)
CMOS Mode—DRVDD = 1.8 V
Data Propagation Delay (tPD)2
DCO Propagation Delay (tDCO)
Setup Time (tS)
Hold Time (tH)
LVDS Mode—DRVDD = 1.8 V
Data Propagation Delay (tPD)2
DCO Propagation Delay (tDCO)
CMOS Mode Pipeline Delay (Latency)
LVDS Mode Pipeline Delay (Latency)
Channel A/Channel B
Aperture Delay (tA)
Aperture Uncertainty (Jitter, tJ)
Wake-Up Time3
OUT-OF-RANGE RECOVERY TIME
1
2
3
Temperature
Min
AD9627-80
Typ
Max
Full
Min
AD9627-105
Typ
Max
625
Full
Full
Full
20
10
12.5
Full
Full
Full
Full
3.75
5.63
1.6
0.8
Full
Full
Full
Full
Unit
625
MHz
105
105
MSPS
MSPS
ns
80
80
20
10
9.5
6.25
6.25
8.75
6.88
2.85
4.28
1.6
0.8
4.75
4.75
6.65
5.23
ns
ns
ns
ns
2.2
3.8
4.5
5.0
6.25
5.75
6.4
6.8
2.2
3.8
4.5
5.0
5.25
4.25
6.4
6.8
ns
ns
ns
ns
Full
Full
Full
Full
2.4
4.0
5.2
5.6
6.65
5.85
6.9
7.3
2.4
4.0
5.2
5.6
5.15
4.35
6.9
7.3
ns
ns
ns
ns
Full
Full
Full
Full
2.0
5.2
4.8
7.3
12
12/12.5
6.3
9.0
2.0
5.2
4.8
7.3
12
12/12.5
6.3
9.0
ns
ns
Cycles
Cycles
Full
Full
Full
Full
1.0
0.1
350
2
Conversion rate is the clock rate after the divider.
Output propagation delay is measured from CLK 50% transition to DATA 50% transition, with 5 pF load.
Wake-up time is dependent on the value of the decoupling capacitors.
Rev. B | Page 11 of 76
1.0
0.1
350
2
ns
ps rms
μs
Cycles
AD9627
SWITCHING SPECIFICATIONS—AD9627-125/AD9627-150
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, maximum sample rate, VIN = −1.0 dBFS differential input, 1.0 V internal reference, and
DCS enabled, unless otherwise noted.
Table 7.
Parameter
CLOCK INPUT PARAMETERS
Input Clock Rate
Conversion Rate
DCS Enabled1
DCS Disabled1
CLK Period—Divide-by-1 Mode (tCLK)
CLK Pulse Width High
Divide-by-1 Mode, DCS Enabled
Divide-by-1 Mode, DCS Disabled
Divide-by-2 Mode, DCS Enabled
Divide-by-3-Through-8 Mode,
DCS Enabled
DATA OUTPUT PARAMETERS (DATA, FD)
CMOS Mode—DRVDD = 3.3 V
Data Propagation Delay (tPD)2
DCO Propagation Delay (tDCO)
Setup Time (tS)
Hold Time (tH)
CMOS Mode—DRVDD = 1.8 V
Data Propagation Delay (tPD)2
DCO Propagation Delay (tDCO)
Setup Time (tS)
Hold Time (tH)
LVDS Mode—DRVDD = 1.8 V
Data Propagation Delay (tPD)2
DCO Propagation Delay (tDCO)
CMOS Mode Pipeline Delay (Latency)
LVDS Mode Pipeline Delay (Latency)
Channel A/Channel B
Aperture Delay (tA)
Aperture Uncertainty (Jitter, tJ)
Wake-Up Time3
OUT-OF-RANGE RECOVERY TIME
Temperature
Min
AD9627-125
Typ
Max
Full
Min
AD9627-150
Typ
Max
625
Full
Full
Full
20
10
8
Full
Full
Full
Full
2.4
3.6
1.6
0.8
Full
Full
Full
Full
Unit
625
MHz
150
150
MSPS
MSPS
ns
125
125
20
10
6.66
4
4
5.6
4.4
2.0
3.0
1.6
0.8
3.33
3.33
4.66
3.66
ns
ns
ns
ns
2.2
3.8
4.5
5.0
4.5
3.5
6.4
6.8
2.2
3.8
4.5
5.0
3.83
2.83
6.4
6.8
ns
ns
ns
ns
Full
Full
Full
Full
2.4
4.0
5.2
5.6
4.4
3.6
6.9
7.3
2.4
4.0
5.2
5.6
3.73
2.93
6.9
7.3
ns
ns
ns
ns
Full
Full
Full
Full
2.0
5.2
4.8
7.3
12
12/12.5
6.3
9.0
2.0
5.2
4.8
7.3
12
12/12.5
6.3
9.0
ns
ns
Cycles
Cycles
Full
Full
Full
Full
1.0
0.1
350
3
1
Conversion rate is the clock rate after the divider.
Output propagation delay is measured from CLK 50% transition to DATA 50% transition, with 5 pF load.
3
Wake-up time is dependent on the value of the decoupling capacitors.
2
Rev. B | Page 12 of 76
1.0
0.1
350
3
ns
ps rms
μs
Cycles
AD9627
TIMING SPECIFICATIONS
Table 8.
Parameter
SYNC TIMING REQUIREMENTS
tSSYNC
tHSYNC
SPI TIMING REQUIREMENTS
tDS
tDH
tCLK
tS
tH
tHIGH
tLOW
tEN_SDIO
Conditions
Min
Typ
SYNC to rising edge of CLK setup time
SYNC to rising edge of CLK hold time
tDIS_SDIO
SPORT TIMING REQUIREMENTS
tCSSCLK
tSSCLKSDO
tSSCLKSDFS
Max
0.24
0.40
Unit
ns
ns
Setup time between the data and the rising edge of SCLK
Hold time between the data and the rising edge of SCLK
Period of the SCLK
Setup time between CSB and SCLK
Hold time between CSB and SCLK
SCLK pulse width high
SCLK pulse width low
Time required for the SDIO pin to switch from an input to an
output relative to the SCLK falling edge
Time required for the SDIO pin to switch from an output to an
input relative to the SCLK rising edge
2
2
40
2
2
10
10
10
ns
ns
ns
ns
ns
ns
ns
ns
10
ns
Delay from rising edge of CLK+ to rising edge of SMI SCLK
Delay from rising edge of SMI SCLK to SMI SDO
Delay from rising edge of SMI SCLK to SMI SDFS
3.2
−0.4
−0.4
4.5
0
0
6.2
0.4
0.4
Timing Diagrams
N+2
N+1
N+3
N
N+4
tA
N+8
N+5
N+6
N+7
tCLK
CLK+
CLK–
N – 13
N – 12
N – 11
N – 10
N–9
N–8
N–7
N–6
N–5
N–4
CH A/CH B FAST
DETECT
N–3
N–2
N–1
N
N+1
N+2
N+3
N+4
N+5
N+6
tS
tH
tDCO
tCLK
DCOA/DCOB
Figure 2. CMOS Output Mode Data and Fast Detect Output Timing (Fast Detect Mode Select Bits = 000)
Rev. B | Page 13 of 76
06571-002
tPD
CH A/CH B DATA
ns
ns
ns
AD9627
N+1
N+2
N+3
N
N+4
N+8
tA
N+5
N+6
N+7
tCLK
CLK+
CLK–
tPD
CH A/CH B DATA
A
CH A/CH B FAST
DETECT
A
B
N – 13
B
N–7
A
B
N – 12
A
B
N – 11
B
N–6
A
A
B
N–5
A
B
N – 10
A
B
N–4
A
B
N–9
A
B
N–3
A
B
A
N–8
A
N–7
B
A
N–2
tDCO
B
B
N–1
A
B
A
N–6
A
B
B
N–5
A
N
B
N+1
A
N–4
A
N+2
tCLK
06571-003
DCO+
DCO–
Figure 3. LVDS Mode Data and Fast Detect Output Timing (Fast Detect Mode Select Bits = 001 Through Fast Detect Mode Select Bits = 100)
CLK+
tHSYNC
06571-004
tSSYNC
SYNC
Figure 4. SYNC Input Timing Requirements
CLK+
CLK–
tCSSCLK
SMI SCLK
tSSCLKSDFS
tSSCLKSDO
SMI SDO
DATA
Figure 5. Signal Monitor SPORT Output Timing (Divide-by-2 Mode)
Rev. B | Page 14 of 76
DATA
06571-005
SMI SDFS
AD9627
ABSOLUTE MAXIMUM RATINGS
THERMAL CHARACTERISTICS
Table 9.
Parameter
ELECTRICAL
AVDD, DVDD to AGND
DRVDD to DRGND
AGND to DRGND
AVDD to DRVDD
VIN+A/VIN+B, VIN−A/VIN−B to AGND
CLK+, CLK− to AGND
SYNC to AGND
VREF to AGND
SENSE to AGND
CML to AGND
RBIAS to AGND
CSB to AGND
SCLK/DFS to DRGND
SDIO/DCS to DRGND
SMI SDO/OEB
SMI SCLK/PDWN
SMI SDFS
D0A/D0B through D11A/D11B to
DRGND
FD0A/FD0B through FD3A/FD3B to
DRGND
DCOA/DCOB to DRGND
ENVIRONMENTAL
Operating Temperature Range
(Ambient)
Maximum Junction Temperature
Under Bias
Storage Temperature Range
(Ambient)
Rating
The exposed paddle must be soldered to the ground plane for
the LFCSP package. Soldering the exposed paddle to the customer
board increases the reliability of the solder joints and maximizes
the thermal capability of the package.
−0.3 V to +2.0 V
−0.3 V to +3.9 V
−0.3 V to +0.3 V
−3.9 V to +2.0 V
−0.3 V to AVDD + 0.2 V
−0.3 V to +3.9 V
−0.3 V to +3.9 V
−0.3 V to AVDD + 0.2 V
−0.3 V to AVDD + 0.2 V
−0.3 V to AVDD + 0.2 V
−0.3 V to AVDD + 0.2 V
−0.3 V to +3.9 V
−0.3 V to +3.9 V
−0.3 V to DRVDD + 0.3 V
−0.3 V to DRVDD + 0.3 V
−0.3 V to DRVDD + 0.3 V
−0.3 V to DRVDD + 0.3 V
−0.3 V to DRVDD + 0.3 V
Typical θJA is specified for a 4-layer PCB with a solid ground
plane. As shown, airflow improves heat dissipation, which
reduces θJA. In addition, metal in direct contact with the package
leads from metal traces, through holes, ground, and power
planes, reduces the θJA.
−0.3 V to DRVDD + 0.3 V
ESD CAUTION
Table 10. Thermal Resistance
Package
Type
64-Lead LFCSP
9 mm × 9 mm
(CP-64-6)
Airflow
Velocity
(m/s)
0
1.0
2.0
θJA1, 2
18.8
16.5
15.8
θJC1, 3
0.6
θJB1, 4
6.0
Unit
°C/W
°C/W
°C/W
1
Per JEDEC 51-7, plus JEDEC 25-5 2S2P test board.
Per JEDEC JESD51-2 (still air) or JEDEC JESD51-6 (moving air).
3
Per MIL-Std 883, Method 1012.1.
4
Per JEDEC JESD51-8 (still air).
2
−0.3 V to DRVDD + 0.3 V
−40°C to +85°C
150°C
−65°C to +150°C
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Rev. B | Page 15 of 76
AD9627
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
DRGND
D3B
D2B
D1B
D0B (LSB)
DNC
DNC
DVDD
FD3B
FD2B
FD1B
FD0B
SYNC
CSB
CLK–
CLK+
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
PIN 1
INDICATOR
EXPOSED PADDLE, PIN 0
(BOTTOM OF PACKAGE)
AD9627
PARALLEL CMOS
TOP VIEW
(Not to Scale)
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
SCLK/DFS
SDIO/DCS
AVDD
AVDD
VIN+B
VIN–B
RBIAS
CML
SENSE
VREF
VIN–A
VIN+A
AVDD
SMI SDFS
SMI SCLK/PDWN
SMI SDO/OEB
NOTES
1. DNC = DO NOT CONNECT.
2. THE EXPOSED PAD MUST BE CONNECTED TO ANALOG GROUND.
06571-006
D3A
D4A
D5A
DRGND
DRVDD
D6A
D7A
DVDD
D8A
D9A
D10A
D11A (MSB)
FD0A
FD1A
FD2A
FD3A
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
DRVDD
D4B
D5B
D6B
D7B
D8B
D9B
D10B
D11B (MSB)
DCOB
DCOA
DNC
DNC
D0A (LSB)
D1A
D2A
Figure 6. LFCSP Parallel CMOS Pin Configuration (Top View)
Table 11. Pin Function Descriptions (Parallel CMOS Mode)
Pin No.
Mnemonic
ADC Power Supplies
20, 64
DRGND
1, 21
DRVDD
24, 57
DVDD
36, 45, 46
AVDD
0
AGND
12, 13, 58, 59
DNC
ADC Analog
37
VIN+A
38
VIN−A
44
VIN+B
43
VIN−B
39
VREF
40
SENSE
42
RBIAS
41
CML
49
CLK+
50
CLK−
ADC Fast Detect Outputs
29
FD0A
30
FD1A
31
FD2A
32
FD3A
53
FD0B
54
FD1B
55
FD2B
56
FD3B
Type
Description
Ground
Supply
Supply
Supply
Ground
Digital Output Ground.
Digital Output Driver Supply (1.8 V to 3.3 V).
Digital Power Supply (1.8 V Nominal).
Analog Power Supply (1.8 V Nominal).
Analog Ground. Pin 0 is the exposed thermal pad on the bottom of the package.
Do Not Connect.
Input
Input
Input
Input
Input/Output
Input
Input/Output
Output
Input
Input
Differential Analog Input Pin (+) for Channel A.
Differential Analog Input Pin (−) for Channel A.
Differential Analog Input Pin (+) for Channel B.
Differential Analog Input Pin (−) for Channel B.
Voltage Reference Input/Output.
Voltage Reference Mode Select. See Table 14 for details.
External Reference Bias Resistor.
Common-Mode Level Bias Output for Analog Inputs.
ADC Clock Input—True.
ADC Clock Input—Complement.
Output
Output
Output
Output
Output
Output
Output
Output
Channel A Fast Detect Indicator. See Table 17 for details.
Channel A Fast Detect Indicator. See Table 17 for details.
Channel A Fast Detect Indicator. See Table 17 for details.
Channel A Fast Detect Indicator. See Table 17 for details.
Channel B Fast Detect Indicator. See Table 17 for details.
Channel B Fast Detect Indicator. See Table 17 for details.
Channel B Fast Detect Indicator. See Table 17 for details.
Channel B Fast Detect Indicator. See Table 17 for details.
Rev. B | Page 16 of 76
AD9627
Pin No.
Mnemonic
Digital Input
52
SYNC
Digital Outputs
14
D0A (LSB)
15
D1A
16
D2A
17
D3A
18
D4A
19
D5A
22
D6A
23
D7A
25
D8A
26
D9A
27
D10A
28
D11A (MSB)
60
D0B (LSB)
61
D1B
62
D2B
63
D3B
2
D4B
3
D5B
4
D6B
5
D7B
6
D8B
7
D9B
8
D10B
9
D11B (MSB)
11
DCOA
10
DCOB
SPI Control
48
SCLK/DFS
47
SDIO/DCS
51
CSB
Signal Monitor Port
33
SMI SDO/OEB
35
SMI SDFS
34
SMI SCLK/PDWN
Type
Description
Input
Digital Synchronization Pin. Slave mode only.
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel A CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel B CMOS Output Data.
Channel A Data Clock Output.
Channel B Data Clock Output.
Input
Input/Output
Input
SPI Serial Clock/Data Format Select Pin in External Pin Mode.
SPI Serial Data I/O/Duty Cycle Stabilizer Pin in External Pin Mode.
SPI Chip Select (Active Low).
Input/Output
Output
Input/Output
Signal Monitor Serial Data Output/Output Enable Input (Active Low) in External Pin Mode.
Signal Monitor Serial Data Frame Sync.
Signal Monitor Serial Clock Output/Power-Down Input in External Pin Mode.
Rev. B | Page 17 of 76
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
DRGND
DNC
DNC
FD3+
FD3–
FD2+
FD2–
DVDD
FD1+
FD1–
FD0+
FD0–
SYNC
CSB
CLK–
CLK+
AD9627
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
PIN 1
INDICATOR
EXPOSED PADDLE, PIN 0
(BOTTOM OF PACKAGE)
AD9627
PARALLEL LVDS
TOP VIEW
(Not to Scale)
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
SCLK/DFS
SDIO/DCS
AVDD
AVDD
VIN+B
VIN–B
RBIAS
CML
SENSE
VREF
VIN–A
VIN+A
AVDD
SMI SDFS
SMI SCLK/PDWN
SMI SDO/OEB
NOTES
1. DNC = DO NOT CONNECT.
2. THE EXPOSED PAD MUST BE CONNECTED TO ANALOG GROUND.
06571-007
D5+
D6–
D6+
DRGND
DRVDD
D7–
D7+
DVDD
D8–
D8+
D9–
D9+
D10–
D10+
D11– (MSB)
D11+ (MSB)
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
DRVDD
DNC
DNC
D0– (LSB)
D0+ (LSB)
D1–
D1+
D2–
D2+
DCO–
DCO+
D3–
D3+
D4–
D4+
D5–
Figure 7. LFCSP Interleaved Parallel LVDS Pin Configuration (Top View)
Table 12. Pin Function Descriptions (Interleaved Parallel LVDS Mode)
Pin No.
Mnemonic
ADC Power Supplies
20, 64
DRGND
1, 21
DRVDD
24, 57
DVDD
36, 45, 46 AVDD
0
AGND
DNC
2, 3, 62,
63
ADC Analog
37
VIN+A
38
VIN−A
44
VIN+B
43
VIN−B
39
VREF
40
SENSE
42
RBIAS
41
CML
49
CLK+
50
CLK−
ADC Fast Detect Outputs
54
FD0+
53
FD0−
56
FD1+
55
FD1−
59
FD2+
58
FD2−
61
FD3+
60
FD3−
Digital Input
52
SYNC
Type
Description
Ground
Supply
Supply
Supply
Ground
Digital Output Ground.
Digital Output Driver Supply (1.8 V to 3.3 V).
Digital Power Supply (1.8 V Nominal).
Analog Power Supply (1.8 V Nominal).
Analog Ground. Pin 0 is the exposed thermal pad on the bottom of the package.
Do Not Connect.
Input
Input
Input
Input
Input/Output
Input
Input/Output
Output
Input
Input
Differential Analog Input Pin (+) for Channel A.
Differential Analog Input Pin (−) for Channel A.
Differential Analog Input Pin (+) for Channel B.
Differential Analog Input Pin (−) for Channel B.
Voltage Reference Input/Output.
Voltage Reference Mode Select. See Table 14 for details.
External Reference Bias Resistor.
Common-Mode Level Bias Output for Analog Inputs.
ADC Clock Input—True.
ADC Clock Input—Complement.
Output
Output
Output
Output
Output
Output
Output
Output
Channel A/Channel B LVDS Fast Detect Indicator 0—True. See Table 17 for details.
Channel A/Channel B LVDS Fast Detect Indicator 0—Complement. See Table 17 for details.
Channel A/Channel B LVDS Fast Detect Indicator 1—True. See Table 17 for details.
Channel A/Channel B LVDS Fast Detect Indicator 1—Complement. See Table 17 for details.
Channel A/Channel B LVDS Fast Detect Indicator 2—True. See Table 17 for details.
Channel A/Channel B LVDS Fast Detect Indicator 2—Complement. See Table 17 for details.
Channel A/Channel B LVDS Fast Detect Indicator 3—True. See Table 17 for details.
Channel A/Channel B LVDS Fast Detect Indicator 3—Complement. See Table 17 for details.
Input
Digital Synchronization Pin. Slave mode only.
Rev. B | Page 18 of 76
AD9627
Pin No.
Mnemonic
Digital Outputs
5
D0+ (LSB)
4
D0− (LSB)
7
D1+
6
D1−
9
D2+
8
D2−
13
D3+
12
D3−
15
D4+
14
D4−
17
D5+
16
D5−
19
D6+
18
D6−
23
D7+
22
D7−
26
D8+
25
D8−
28
D9+
27
D9−
30
D10+
29
D10−
32
D11+ (MSB)
31
D11− (MSB)
11
DCO+
10
DCO−
SPI Control
48
SCLK/DFS
47
SDIO/DCS
51
CSB
Signal Monitor Port
33
SMI SDO/OEB
35
SMI SDFS
34
SMI SCLK/PDWN
Type
Description
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
Channel A/Channel B LVDS Output Data 0—True.
Channel A/Channel B LVDS Output Data 0—Complement.
Channel A/Channel B LVDS Output Data 1—True.
Channel A/Channel B LVDS Output Data 1—Complement.
Channel A/Channel B LVDS Output Data 2—True.
Channel A/Channel B LVDS Output Data 2—Complement.
Channel A/Channel B LVDS Output Data 3—True.
Channel A/Channel B LVDS Output Data 3—Complement.
Channel A/Channel B LVDS Output Data 4 —True.
Channel A/Channel B LVDS Output Data 4—Complement.
Channel A/Channel B LVDS Output Data 5—True.
Channel A/Channel B LVDS Output Data 5—Complement.
Channel A/Channel B LVDS Output Data 6—True.
Channel A/Channel B LVDS Output Data 6—Complement.
Channel A/Channel B LVDS Output Data 7—True.
Channel A/Channel B LVDS Output Data 7—Complement.
Channel A/Channel B LVDS Output Data 8—True.
Channel A/Channel B LVDS Output Data 8—Complement.
Channel A/Channel B LVDS Output Data 9—True.
Channel A/Channel B LVDS Output Data 9—Complement.
Channel A/Channel B LVDS Output Data 10—True.
Channel A/Channel B LVDS Output Data 10—Complement.
Channel A/Channel B LVDS Output Data 11—True.
Channel A/Channel B LVDS Output Data 11—Complement.
Channel A/Channel B LVDS Data Clock Output—True.
Channel A/Channel B LVDS Data Clock Output—Complement.
Input
Input/Output
Input
SPI Serial Clock/Data Format Select Pin in External Pin Mode.
SPI Serial Data I/O/Duty Cycle Stabilizer Pin in External Pin Mode.
SPI Chip Select (Active Low).
Input/Output
Output
Input/Output
Signal Monitor Serial Data Output/Output Enable Input (Active Low) in External Pin Mode.
Signal Monitor Serial Data Frame Sync.
Signal Monitor Serial Clock Output/Power-Down Input in External Pin Mode.
Rev. B | Page 19 of 76
AD9627
EQUIVALENT CIRCUITS
1kΩ
SCLK/DFS
26kΩ
06571-008
06571-012
VIN
Figure 8. Equivalent Analog Input Circuit
Figure 12. Equivalent SCLK/DFS Input Circuit
AVDD
1kΩ
1.2V
10kΩ
SENSE
10kΩ
CLK+
06571-009
06571-013
CLK–
Figure 13. Equivalent SENSE Circuit
Figure 9. Equivalent Clock Input Circuit
DRVDD
AVDD
26kΩ
1kΩ
06571-010
06571-014
CSB
DRGND
Figure 10. Digital Output
Figure 14. Equivalent CSB Input Circuit
AVDD
DRVDD
DRVDD
VREF
26kΩ
6kΩ
1kΩ
06571-015
06571-011
SDIO/DCS
Figure 11. Equivalent SDIO/DCS or SMI SDFS Circuit
Figure 15. Equivalent VREF Circuit
Rev. B | Page 20 of 76
AD9627
TYPICAL PERFORMANCE CHARACTERISTICS
AVDD = 1.8 V, DVDD = 1.8 V, DRVDD = 3.3 V, sample rate = 150 MSPS, DCS enabled, 1.0 V internal reference, 2 V p-p differential input,
VIN = −1.0 dBFS, and 64k sample, TA = 25°C, unless otherwise noted.
0
0
150MSPS
2.3MHz @ –1dBFS
SNR = 69.4dBc (70.4dBFS)
ENOB = 11.4 BITS
SFDR = 86.5dBc
–20
AMPLITUDE (dBFS)
–40
–60
SECOND
HARMONIC
THIRD
HARMONIC
–80
10
20
30
40
50
60
70
THIRD
HARMONIC
SECOND
HARMONIC
FREQUENCY (MHz)
–120
06571-016
0
0
10
20
30
40
50
60
70
FREQUENCY (MHz)
Figure 16. AD9627-150 Single-Tone FFT with fIN = 2.3 MHz
Figure 19. AD9627-150 Single-Tone FFT with fIN = 140 MHz
0
0
150MSPS
30.3MHz @ –1dBFS
SNR = 69.3dBc (70.3dBFS)
ENOB = 11.4 BITS
SFDR = 84.0dBc
–40
–60
THIRD
HARMONIC
–80
150MSPS
220MHz @ –1dBFS
SNR = 68.2dBc (69.2dBFS)
ENOB = 11.2 BITS
SFDR = 77.0dBc
–20
AMPLITUDE (dBFS)
–20
SECOND
HARMONIC
–100
–40
–60
SECOND
HARMONIC
THIRD
HARMONIC
–80
–100
0
10
20
30
40
50
60
70
FREQUENCY (MHz)
–120
06571-017
–120
0
10
20
30
40
50
60
70
FREQUENCY (MHz)
Figure 17. AD9627-150 Single-Tone FFT with fIN = 30.3 MHz
06571-020
AMPLITUDE (dBFS)
–80
–100
–120
Figure 20. AD9627-150 Single-Tone FFT with fIN = 220 MHz
0
0
150MSPS
70MHz @ –1dBFS
SNR = 69.2dBc (70.2dBFS)
ENOB = 11.4 BITS
SFDR = 84.0dBc
–40
–60
THIRD
HARMONIC
SECOND
HARMONIC
–80
150MSPS
337MHz @ –1dBFS
SNR = 67.6dBc (68.6dBFS)
ENOB = 11.1 BITS
SFDR = 74.0dBc
–20
AMPLITUDE (dBFS)
–20
–100
–40
–60
THIRD
HARMONIC
SECOND
HARMONIC
–80
–100
–120
0
10
20
30
40
50
60
70
FREQUENCY (MHz)
06571-018
AMPLITUDE (dBFS)
–60
06571-019
–100
–40
Figure 18. AD9627-150 Single-Tone FFT with fIN = 70 MHz
–120
0
10
20
30
40
50
60
70
FREQUENCY (MHz)
Figure 21. AD9627-150 Single-Tone FFT with fIN = 337 MHz
Rev. B | Page 21 of 76
06571-021
AMPLITUDE (dBFS)
–20
150MSPS
140MHz @ –1dBFS
SNR = 68.8dBc (69.8dBFS)
ENOB = 11.3 BITS
SFDR = 83.5dBc
AD9627
0
0
150MSPS
440MHz @ –1dBFS
SNR = 65.7dBc (66.7dBFS)
ENOB = 10.4 BITS
SFDR = 70.0dBc
–20
AMPLITUDE (dBFS)
–40
SECOND
HARMONIC
–60
THIRD
HARMONIC
–80
10
20
30
40
50
60
70
THIRD
HARMONIC
FREQUENCY (MHz)
–120
06571-022
0
0
10
20
30
40
50
60
FREQUENCY (MHz)
Figure 25. AD9627-125 Single-Tone FFT with fIN = 70 MHz
Figure 22. AD9627-150 Single-Tone FFT with fIN = 440 MHz
0
0
125MSPS
2.3MHz @ –1dBFS
SNR = 69.5dBc (70.5dBFS)
ENOB = 11.4 BITS
SFDR = 86.5dBc
–40
–60
SECOND
HARMONIC
–80
125MSPS
140MHz @ –1dBFS
SNR = 69.1dBc (70.1dBFS)
ENOB = 11.3 BITS
SFDR = 84dBc
–20
AMPLITUDE (dBFS)
–20
THIRD
HARMONIC
–40
–60
SECOND
HARMONIC
–80
THIRD
HARMONIC
–100
–100
0
10
20
30
40
50
60
FREQUENCY (MHz)
–120
06571-023
–120
0
10
20
30
40
50
60
FREQUENCY (MHz)
06571-026
AMPLITUDE (dBFS)
SECOND
HARMONIC
–80
–100
–120
Figure 26. AD9627-125 Single-Tone FFT with fIN = 140 MHz
Figure 23. AD9627-125 Single-Tone FFT with fIN = 2.3 MHz
0
0
125MSPS
30.3MHz @ –1dBFS
SNR = 69.4dBc (70.4dBFS)
ENOB = 11.4 BITS
SFDR = 85dBc
–40
–60
THIRD
HARMONIC
–80
125MSPS
337MHz @ –1dBFS
SNR = 67.6dBc (68.6dBFS)
ENOB = 11.1 BITS
SFDR = 74dBc
–20
AMPLITUDE (dBFS)
–20
SECOND
HARMONIC
–40
–60
SECOND
HARMONIC
THIRD
HARMONIC
–80
–100
–100
–120
0
10
20
30
40
50
60
FREQUENCY (MHz)
06571-024
AMPLITUDE (dBFS)
–60
06571-025
–100
–40
Figure 24. AD9627-125 Single-Tone FFT with fIN = 30.3 MHz
–120
0
10
20
30
40
50
60
FREQUENCY (MHz)
Figure 27. AD9627-125 Single-Tone FFT with fIN = 337 MHz
Rev. B | Page 22 of 76
06571-027
AMPLITUDE (dBFS)
–20
125MSPS
70MHz @ –1dBFS
SNR = 69.4dBc (70.4dBFS)
ENOB = 11.4 BITS
SFDR = 85dBc
AD9627
120
95
SFDR = +85°C
SFDR (dBFS)
90
85
80
SFDR = +25°C
SNR/SFDR (dBc)
SNR (dBFS)
60
40
80
SFDR = –40°C
75
70
SFDR (dBc)
65
85dB REFERENCE LINE
SNR = +25°C
SNR = +85°C
SNR = –40°C
20
60
SNR (dBc)
–80
–70
–60
–50
–40
–30
–20
–10
0
INPUT AMPLITUDE (dBFS)
55
06571-028
0
–90
0
50
100
150
200
250
300
350
400
450
INPUT FREQUENCY (MHz)
Figure 28. AD9627-150 Single-Tone SNR/SFDR vs. Input Amplitude (AIN)
with fIN = 2.4 MHz
06571-031
SNR/SFDR (dBc AND dBFS)
100
Figure 31. AD9627-150 Single-Tone SNR/SFDR vs.
Input Frequency (fIN) and Temperature with 1 V p-p Full Scale
100
–2.5
0.5
SFDR (dBFS)
–3.0
60
SFDR (dBc)
40
0.4
GAIN
–3.5
0.3
OFFSET
–4.0
0.2
–4.5
0.1
85dB REFERENCE LINE
20
OFFSET ERROR (%FSR)
SNR (dBFS)
GAIN ERROR (%FSR)
SNR/SFDR (dBc AND dBFS)
80
–80
–70
–60
–50
–40
–30
–20
–10
0
INPUT AMPLITUDE (dBFS)
–5.0
–40
0
–20
0
20
40
60
06571-032
0
–90
06571-029
SNR (dBc)
80
TEMPERATURE (°C)
Figure 29. AD9627-150 Single-Tone SNR/SFDR vs. Input Amplitude (AIN) with
fIN = 98.12 MHz
Figure 32. AD9627-150 Gain and Offset vs. Temperature
95
0
SFDR (dBc)
90
–20
SFDR/IMD3 (dBc AND dBFS)
SFDR = +85°C
SFDR = +25°C
80
SFDR = –40°C
75
70
SNR = +25°C
SNR = +85°C
SNR = –40°C
65
IMD3 (dBc)
–40
–60
–80
SFDR (dBFS)
–100
60
0
50
100
150
200
250
300
350
400
450
INPUT FREQUENCY (MHz)
Figure 30. AD9627-150 Single-Tone SNR/SFDR vs.
Input Frequency (fIN) and Temperature with 2 V p-p Full Scale
–120
–90
–78
–66
–54
–42
–30
INPUT AMPLITUDE (dBFS)
–18
–6
06571-033
IMD3 (dBFS)
55
06571-030
SNR/SFDR (dBc)
85
Figure 33. AD9627-150 Two-Tone SFDR/IMD3 vs. Input Amplitude (AIN)
with fIN1 = 29.1 MHz, fIN2 = 32.1 MHz, fS = 150 MSPS
Rev. B | Page 23 of 76
AD9627
0
0
–20
SFDR (dBc)
AMPLITUDE (dBFS)
SFDR/IMD3 (dBc AND dBFS)
–20
150MSPS
169.1MHz @ –7dBFS
172.1MHz @ –7dBFS
SFDR = 83.8dBc (90.8dBFS)
–40
IMD3 (dBc)
–60
–80
–40
–60
–80
SFDR (dBFS)
–100
–100
IMD3 (dBFS)
–66
–54
–42
–30
–18
–6
INPUT AMPLITUDE (dBFS)
–120
0
30
40
50
60
70
Figure 37. AD9627-150 Two-Tone FFT with fIN1 = 169.1 MHz and
fIN2 = 172.1 MHz
0
0
NPR = 61.5dBc
NOTCH @ 18.5MHz
NOTCH WIDTH = 3MHz
–20
AMPLITUDE (dBFS)
–20
–40
–60
–80
–100
–40
–60
–80
–100
0
15.36
30.72
46.08
61.44
FREQUENCY (MHz)
–120
06571-035
–120
0
10
20
30
40
50
60
06571-038
AMPLITUDE (dBFS)
20
FREQUENCY (MHz)
Figure 34. AD9627-150 Two-Tone SFDR/IMD3 vs. Input Amplitude (AIN)
with fIN1 = 169.1 MHz, fIN2 = 172.1 MHz, fS = 150 MSPS
70
FREQUENCY (MHz)
Figure 35. AD9627-125, Two 64k WCDMA Carriers
with fIN = 170 MHz, fS = 122.88 MSPS
Figure 38. AD9627-150 Noise Power Ratio (NPR)
0
100
150MSPS
29.1MHz @ –7dBFS
32.1MHz @ –7dBFS
SFDR = 86.1dBc (93.1dBFS)
–20
SFDR - SIDE B
90
–40
SNR/SFDR (dBc)
AMPLITUDE (dBFS)
10
06571-037
–78
06571-034
–120
–90
–60
–80
SFDR - SIDE A
80
SNR - SIDE B
70
SNR - SIDE A
–120
0
10
20
30
40
50
FREQUENCY (MHz)
60
70
06571-036
–100
Figure 36. AD9627-150 Two-Tone FFT with fIN1 = 29.1 MHz and fIN2 = 32.1 MHz
Rev. B | Page 24 of 76
50
0
25
50
75
100
125
150
SAMPLE RATE (MSPS)
Figure 39. AD9627-150 Single-Tone SNR/SFDR vs. Sample Rate (fS)
with fIN = 2.3 MHz
06571-039
60
AD9627
12
100
0.3 LSB rms
95
90
8
SNR/SFDR (dBc)
NUMBER OF HITS (1M)
10
6
4
SFDR DCS ON
85
80
SFDR DCS OFF
75
SNR DCS ON
70
2
65
N–2
N–1
N
N+1
N+2
N+3
OUTPUT CODE
06571-040
N–3
60
20
60
80
DUTY CYCLE (%)
Figure 40. AD9627 Grounded Input Histogram
Figure 43. AD9627-150 SNR/SFDR vs. Duty Cycle with fIN = 10.3 MHz
0.4
95
0.3
90
0.2
SFDR
85
SNR/SFDR (dBc)
INL ERROR (LSB)
40
06571-043
SNR DCS OFF
0
0.1
0
–0.1
80
75
70
–0.2
SNR
0
512
1024
1536
2048
2560
3072
3584
4096
OUTPUT CODE
06571-041
–0.4
Figure 41. AD9627 INL with fIN = 10.3 MHz
0.05
–0.05
–0.15
–0.25
1024
1536
2048
2560
3072
3584
OUTPUT CODE
4096
06571-042
DNL ERROR (LSB)
0.15
512
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
INPUT COMMON-MODE VOLTAGE (V)
Figure 44. AD9627-150 SNR/SFDR vs. Input Common Mode (VCM)
with fIN = 30 MHz
0.25
0
60
0.2
Figure 42. AD9627 DNL with fIN = 10.3 MHz
Rev. B | Page 25 of 76
06571-044
65
–0.3
AD9627
THEORY OF OPERATION
The AD9627 dual ADC design can be used for diversity reception
of signals, where the ADCs are operating identically on the same
carrier but from two separate antennae. The ADCs can also be
operated with independent analog inputs. The user can sample
any fS/2 frequency segment from dc to 200 MHz, using appropriate
low-pass or band-pass filtering at the ADC inputs with little loss
in ADC performance. Operation to 450 MHz analog input is
permitted but occurs at the expense of increased ADC noise and
distortion.
In nondiversity applications, the AD9627 can be used as a baseband or direct downconversion receiver, where one ADC is
used for I input data, and the other is used for Q input data.
Synchronizaton capability is provided to allow synchronized
timing between multiple channels or multiple devices.
A small resistor in series with each input can help reduce the
peak transient current required from the output stage of the
driving source. A shunt capacitor can be placed across the
inputs to provide dynamic charging currents. This passive
network creates a low-pass filter at the ADC input; therefore,
the precise values are dependent on the application.
In intermediate frequency (IF) undersampling applications, any
shunt capacitors should be reduced. In combination with the
driving source impedance, the shunt capacitors limit the input
bandwidth. Refer to Application Note AN-742, Frequency
Domain Response of Switched-Capacitor ADCs; Application Note
AN-827, A Resonant Approach to Interfacing Amplifiers to
Switched-Capacitor ADCs; and the Analog Dialogue article,
“Transformer-Coupled Front-End for Wideband A/D Converters,”
for more information on this subject (see www.analog.com).
Programming and control of the AD9627 are accomplished
using a 3-bit SPI-compatible serial interface.
S
CH
ADC ARCHITECTURE
S
CS
The AD9627 architecture consists of a dual front-end sampleand-hold amplifier (SHA), followed by a pipelined, switched
capacitor ADC. The quantized outputs from each stage are
combined into a final 12-bit result in the digital correction logic.
The pipelined architecture permits the first stage to operate on
a new input sample and the remaining stages to operate on the
preceding samples. Sampling occurs on the rising edge of the clock.
Each stage of the pipeline, excluding the last, consists of a low
resolution flash ADC connected to a switched capacitor digitalto-analog converter (DAC) and an interstage residue amplifier
(MDAC). The residue amplifier magnifies the difference between
the reconstructed DAC output and the flash input for the next
stage in the pipeline. One bit of redundancy is used in each stage
to facilitate digital correction of flash errors. The last stage simply
consists of a flash ADC.
The input stage of each channel contains a differential SHA that
can be ac- or dc-coupled in differential or single-ended modes.
The output staging block aligns the data, corrects errors, and passes
the data to the output buffers. The output buffers are powered from
a separate supply, allowing adjustment of the output voltage swing.
During power-down, the output buffers go into a high impedance
state.
ANALOG INPUT CONSIDERATIONS
The analog input to the AD9627 is a differential switched
capacitor SHA that has been designed for optimum performance
while processing a differential input signal.
The clock signal alternatively switches the SHA between sample
mode and hold mode (see Figure 45). When the SHA is switched
into sample mode, the signal source must be capable of charging
the sample capacitors and settling within 1/2 of a clock cycle.
VIN+
CPIN, PAR
S
H
CS
VIN–
S
06571-045
CH
CPIN, PAR
Figure 45. Switched-Capacitor SHA Input
For best dynamic performance, the source impedances driving
VIN+ and VIN− should be matched.
An internal differential reference buffer creates positive and
negative reference voltages that define the input span of the ADC
core. The span of the ADC core is set by this buffer to 2 × VREF.
Input Common Mode
The analog inputs of the AD9627 are not internally dc biased.
In ac-coupled applications, the user must provide this bias
externally. Setting the device so that VCM = 0.55 × AVDD
is recommended for optimum performance, but the device
functions over a wider range with reasonable performance
(see Figure 44). An on-board common-mode voltage reference
is included in the design and is available from the CML pin.
Optimum performance is achieved when the common-mode
voltage of the analog input is set by the CML pin voltage
(typically 0.55 × AVDD). The CML pin must be decoupled to
ground by a 0.1 μF capacitor, as described in the Applications
Information section.
Differential Input Configurations
Optimum performance is achieved while driving the AD9627 in a
differential input configuration. For baseband applications, the
AD8138, ADA4937-2, and ADA4938-2 differential drivers provide
excellent performance and a flexible interface to the ADC.
Rev. B | Page 26 of 76
AD9627
An alternative to using a transformer-coupled input at frequencies
in the second Nyquist zone is to use the AD8352 differential driver.
An example is shown in Figure 50. See the AD8352 data sheet
for more information.
The output common-mode voltage of the AD8138 is easily set
with the CML pin of the AD9627 (see Figure 46), and the driver
can be configured in a Sallen-Key filter topology to provide
band limiting of the input signal.
499Ω
1V p-p
R
49.9Ω
VIN+
In any configuration, the value of Shunt Capacitor C is dependent
on the input frequency and source impedance and may need to
be reduced or removed. Table 13 displays recommended values to
set the RC network. However, these values are dependent on the
input signal and should be used only as a starting guide.
AVDD
499Ω
R
CML
VIN–
06571-046
523Ω
AD9627
C
AD8138
0.1µF
499Ω
Table 13. Example RC Network
Figure 46. Differential Input Configuration Using the AD8138
For baseband applications where SNR is a key parameter,
differential transformer coupling is the recommended input
configuration. An example is shown in Figure 47. To bias the
analog input, the CML voltage can be connected to the center
tap of the secondary winding of the transformer.
R Series
(Ω Each)
33
33
15
15
Frequency Range (MHz)
0 to 70
70 to 200
200 to 300
>300
C Differential (pF)
15
5
5
Open
R
VIN+
Single-Ended Input Configuration
AD9627
R
A single-ended input can provide adequate performance in cost
sensitive applications. In this configuration, SFDR and distortion
performance degrade due to the large input common-mode swing.
If the source impedances on each input are matched, there should
be little effect on SNR performance. Figure 48 shows a typical
single-ended input configuration.
CML
06571-047
VIN–
0.1µF
Figure 47. Differential Transformer-Coupled Configuration
The signal characteristics must be considered when selecting
a transformer. Most RF transformers saturate at frequencies
below a few megahertz (MHz). Excessive signal power can also
cause core saturation, which leads to distortion.
1kΩ
R
49.9Ω
1V p-p
At input frequencies in the second Nyquist zone and above, the
noise performance of most amplifiers is not adequate to achieve
the true SNR performance of the AD9627. For applications where
SNR is a key parameter, differential double balun coupling is the
recommended input configuration (see Figure 49).
0.1µF
AVDD
10µF
0.1µF
AVDD
0.1µF
AD9627
C
1kΩ
10µF
VIN+
1kΩ
R
VIN–
1kΩ
06571-048
C
Figure 48. Single-Ended Input Configuration
0.1µF
R
VIN+
2V p-p
25Ω
S
S
P
AD9627
C
25Ω
0.1µF
0.1µF
R
CML
VIN–
06571-049
PA
Figure 49. Differential Double Balun Input Configuration
VCC
0.1µF
0Ω
ANALOG INPUT
16
0.1µF
8, 13
1
11
0.1µF
CD
RD
RG
3
200Ω
AD8352
10
4
5
ANALOG INPUT
0.1µF
0Ω
R
VIN+
2
C
0.1µF
200Ω
R
AD9627
VIN–
CML
14
0.1µF
0.1µF
Figure 50. Differential Input Configuration Using the AD8352
Rev. B | Page 27 of 76
06571-050
2V p-p
49.9Ω
AD9627
A stable and accurate voltage reference is built into the AD9627.
The input range can be adjusted by varying the reference voltage
applied to the AD9627, using either the internal reference or an
externally applied reference voltage. The input span of the ADC
tracks reference voltage changes linearly. The various reference
modes are summarized in the sections that follow. The Reference
Decoupling section describes the best practices PCB layout of
the reference.
The input range of the ADC always equals twice the voltage at
the reference pin for either an internal or an external reference.
VIN+A/VIN+B
VIN–A/VIN–B
ADC
CORE
VREF
1.0µF
Internal Reference Connection
A comparator within the AD9627 detects the potential at the
SENSE pin and configures the reference into four possible
modes, which are summarized in Table 14. If SENSE is grounded,
the reference amplifier switch is connected to the internal resistor
divider (see Figure 51), setting VREF to 1.0 V. Connecting the
SENSE pin to VREF switches the reference amplifier output
to the SENSE pin, completing the loop and providing a 0.5 V
reference output.
VIN+A/VIN+B
VIN–A/VIN–B
SELECT
LOGIC
0.5V
R1
AD9627
Figure 52. Programmable Reference Configuration
If the internal reference of the AD9627 is used to drive multiple
converters to improve gain matching, the loading of the reference
by the other converters must be considered. Figure 53 shows
how the internal reference voltage is affected by loading.
0
REFERENCE VOLTAGE ERROR (%)
VREF = 0.5V
VREF
0.1µF
SELECT
LOGIC
SENSE
06571-051
0.5V
AD9627
R2
SENSE
ADC
CORE
1.0µF
0.1µF
06571-052
VOLTAGE REFERENCE
–0.25
VREF = 1.0V
–0.50
–0.75
–1.00
If a resistor divider is connected external to the chip, as shown
in Figure 52, the switch again sets to the SENSE pin. This puts
the reference amplifier in a noninverting mode with the VREF
output defined as follows:
–1.25
0
0.5
1.0
1.5
2.0
LOAD CURRENT (mA)
Figure 53. VREF Accuracy vs. Load
R2 
VREF  0.5  1 

R1 

Table 14. Reference Configuration Summary
Selected Mode
External Reference
SENSE Voltage
AVDD
Resulting VREF (V)
N/A
Resulting Differential Span (V p-p)
2 × external reference
Internal Fixed Reference
VREF
0.5
1.0
Programmable Reference
0.2 V to VREF
Internal Fixed Reference
AGND to 0.2 V
R2 

0.5   1 
 (see Figure 52)
R1 

1.0
Rev. B | Page 28 of 76
2 × VREF
2.0
06571-053
Figure 51. Internal Reference Configuration
AD9627
External Reference Operation
The use of an external reference may be necessary to enhance
the gain accuracy of the ADC or improve thermal drift characteristics. Figure 54 shows the typical drift characteristics of the
internal reference in 1.0 V mode.
2.5
This helps prevent the large voltage swings of the clock from
feeding through to other portions of the AD9627 while preserving
the fast rise and fall times of the signal that are critical to a low
jitter performance.
2.0
1.5
1.0
0.5
0
–0.5
Mini-Circuits®
ADT1–1WT, 1:1Z
0.1µF
XFMR
0.1µF
CLOCK
INPUT
–1.0
ADC
AD9627
0.1µF
–1.5
CLK–
–2.0
SCHOTTKY
DIODES:
HSMS2822
0.1µF
–20
0
20
40
60
80
TEMPERATURE (°C)
06571-054
–2.5
–40
CLK+
100Ω
50Ω
06571-056
REFERENCE VOLTAGE ERROR (mV)
The RF balun configuration is recommended for clock
frequencies between 125 MHz and 625 MHz, and the RF
transformer is recommended for clock frequencies from 10 MHz
to 200 MHz. The back-to-back Schottky diodes across the
transformer/balun secondary limit clock excursions into the
AD9627 to approximately 0.8 V p-p differential.
Figure 56. Transformer-Coupled Differential Clock (Up to 200 MHz)
Figure 54. Typical VREF Drift
1nF
0.1µF
CLOCK
INPUT
CLK+
ADC
AD9627
50Ω
0.1µF
1nF
CLK–
06571-057
When the SENSE pin is tied to AVDD, the internal reference is
disabled, allowing the use of an external reference. An internal
reference buffer loads the external reference with an equivalent
6 kΩ load (see Figure 15). The internal buffer generates the
positive and negative full-scale references for the ADC core.
Therefore, the external reference must be limited to a maximum
of 1.0 V.
SCHOTTKY
DIODES:
HSMS2822
Figure 57. Balun-Coupled Differential Clock (Up to 625 MHz)
CLOCK INPUT CONSIDERATIONS
For optimum performance, the AD9627 sample clock inputs,
CLK+ and CLK−, should be clocked with a differential signal.
The signal is typically ac-coupled into the CLK+ and CLK− pins
via a transformer or capacitors. These pins are biased internally
(see Figure 55) and require no external bias.
If a low jitter clock source is not available, another option is to
ac couple a differential PECL signal to the sample clock input
pins, as shown in Figure 58. The AD9510/AD9511/AD9512/
AD9513/AD9514/AD9515/AD9516 clock drivers offer excellent
jitter performance.
AVDD
0.1µF
0.1µF
CLK–
CLOCK
INPUT
100Ω
0.1µF
ADC
AD9627
CLK–
50kΩ
50kΩ
240Ω
240Ω
2pF
06571-055
Figure 58. Differential PECL Sample Clock (Up to 625 MHz)
Figure 55. Equivalent Clock Input Circuit
Clock Input Options
The AD9627 has a very flexible clock input structure. Clock input
can be a CMOS, LVDS, LVPECL, or sine wave signal. Regardless of
the type of signal being used, clock source jitter is of the most
concern, as described in the Jitter Considerations section.
Figure 56 and Figure 57 show two preferred methods for clocking
the AD9627 (at clock rates up to 625 MHz). A low jitter clock
source is converted from a single-ended signal to a differential
signal using either an RF balun or an RF transformer.
A third option is to ac-couple a differential LVDS signal to the
sample clock input pins, as shown in Figure 59. The AD9510/
AD9511/AD9512/AD9513/AD9514/AD9515/AD9516 clock
drivers offer excellent jitter performance.
0.1µF
0.1µF
CLOCK
INPUT
CLK+
0.1µF
CLOCK
INPUT
Rev. B | Page 29 of 76
AD951x
LVDS DRIVER
100Ω
0.1µF
ADC
AD9627
CLK–
50kΩ
50kΩ
Figure 59. Differential LVDS Sample Clock (Up to 625 MHz)
06571-059
CLK+
CLK+
AD951x
PECL DRIVER
06571-058
1.2V
2pF
0.1µF
CLOCK
INPUT
AD9627
In some applications, it may be acceptable to drive the sample
clock inputs with a single-ended CMOS signal. In such applications, the CLK+ pin should be driven directly from a CMOS gate,
and the CLK− pin should be bypassed to ground with a 0.1 μF
capacitor in parallel with a 39 kΩ resistor (see Figure 60).
CLK+ can be driven directly from a CMOS gate. Although the
CLK+ input circuit supply is AVDD (1.8 V), this input is designed
to withstand input voltages of up to 3.6 V, making the selection
of the drive logic voltage very flexible.
VCC
0.1µF
CLOCK
INPUT
1kΩ
OPTIONAL
0.1µF
100Ω
AD951x
CMOS DRIVER
CLK+
ADC
AD9627
1kΩ
50Ω1
Jitter Considerations
CLK–
150Ω
39kΩ
06571-060
0.1µF
Jitter in the rising edge of the input is still of paramount concern
and is not easily reduced by the internal stabilization circuit.
The duty cycle control loop does not function for clock rates
less than 20 MHz nominally. The loop has a time constant
associated with it thatmust be considered where the clock rate
can change dynamically. A wait time of 1.5 μs to 5 μs is required
after a dynamic clock frequency increase or decrease before the
DCS loop is relocked to the input signal. During the time period
that the loop is not locked, the DCS loop is bypassed, and internal
device timing is dependent on the duty cycle of the input clock
signal. In such applications, it may be appropriate to disable the
duty cycle stabilizer. In all other applications, enabling the DCS
circuit is recommended to maximize ac performance.
RESISTOR IS OPTIONAL.
Figure 60. Single-Ended 1.8 V CMOS Sample Clock (Up to 150 MSPS)
High speed, high resolution ADCs are sensitive to the quality
of the clock input. The degradation in SNR from the low
frequency SNR (SNRLF) at a given input frequency (fINPUT) due
to jitter (tJRMS) can be calculated by
SNRHF = −10 log[(2π × fINPUT × tJRMS)2 + 10 (  SNRLF /10) ]
VCC
0.1µF
CLOCK
INPUT
50Ω1
1kΩ
AD951x
CMOS DRIVER
OPTIONAL 0.1µF
100Ω
1kΩ
0.1µF
In the equation, the rms aperture jitter represents the clock input
jitter specification. IF undersampling applications are particularly
sensitive to jitter, as illustrated in Figure 62.
CLK+
ADC
AD9627
75
150Ω
06571-061
CLK–
RESISTOR IS OPTIONAL.
70
0.05ps
Figure 61. Single-Ended 3.3 V CMOS Sample Clock (Up to 150 MSPS)
MEASURED
0.20ps
The AD9627 contains an input clock divider with the ability to
divide the input clock by integer values between 1 and 8. If a
divide ratio other than 1 is selected, the duty cycle stabilizer is
automatically enabled.
The AD9627 clock divider can be synchronized using the external
SYNC input. Bit 1 and Bit 2 of Register 0x100 allow the clock
divider to be resynchronized on every SYNC signal or only on
the first SYNC signal after the register is written. A valid SYNC
causes the clock divider to reset to its initial state. This synchronization feature allows multiple parts to have their clock dividers
aligned to guarantee simultaneous input sampling.
Clock Duty Cycle
Typical high speed ADCs use both clock edges to generate
a variety of internal timing signals and, as a result, may be
sensitive to clock duty cycle. Commonly, a ±5% tolerance is
required on the clock duty cycle to maintain dynamic
performance characteristics.
The AD9627 contains a duty cycle stabilizer (DCS) that retimes
the nonsampling (falling) edge, providing an internal clock
signal with a nominal 50% duty cycle. This allows the user to
provide a wide range of clock input duty cycles without affecting
the performance of the AD9627. Noise and distortion performance
are nearly flat for a wide range of duty cycles with the DCS on,
as shown in Figure 43.
60
0.5ps
55
1.0ps
1.50ps
50
45
2.00ps
2.50ps
3.00ps
1
10
100
INPUT FREQUENCY (MHz)
1000
06571-062
Input Clock Divider
SNR (dBc)
65
Figure 62. SNR vs. Input Frequency and Jitter
The clock input should be treated as an analog signal in cases
where aperture jitter may affect the dynamic range of the AD9627.
Power supplies for clock drivers should be separated from the
ADC output driver supplies to avoid modulating the clock
signal with digital noise. Low jitter, crystal-controlled oscillators
make the best clock sources. If the clock is generated from another
type of source (by gating, dividing, or another method), it should
be retimed by the original clock at the last step.
Refer to Application Note AN-501 and Application Note AN-756
(see www.analog.com) for more information about jitter performance as it relates to ADCs.
Rev. B | Page 30 of 76
AD9627
1.00
The maximum DRVDD current (IDRVDD) can be calculated as
IDRVDD = VDRVDD × CLOAD × fCLK × N
IAVDD
0.75
TOTAL POWER (W)
As shown in Figure 63 through Figure 66, the power dissipated
by the AD9627 is proportional to its sample rate. In CMOS
output mode, the digital power dissipation is determined
primarily by the strength of the digital drivers and the load
on each output bit.
0.4
TOTAL POWER
0.50
0.1
IDRVDD
IDVDD
IAVDD
IDRVDD
0
50
75
100
125
0
150
SAMPLE RATE (MSPS)
1.25
1.00
0.2
TOTAL POWER
0.1
0.25
0.2
0.50
IDRVDD
SUPPLY CURRENT (A)
0.3
TOTAL POWER
0.1
IDVDD
0
75
100
0
125
SAMPLE RATE (MSPS)
20
40
60
0
80
06571-065
By asserting PDWN (either through the SPI port or by asserting
the PDWN pin high), the AD9627 is placed in power-down
mode. In this state, the ADC typically dissipates 2.5 mW.
During power-down, the output drivers are placed in a high
impedance state. Asserting the PDWN pin low returns the
AD9627 to its normal operating mode. Note that PDWN is
referenced to the digital output driver supply (DRVDD) and
should not exceed that supply voltage.
Low power dissipation in power-down mode is achieved by
shutting down the reference, reference buffer, biasing networks,
and clock. Internal capacitors are discharged when entering powerdown mode and then must be recharged when returning to normal
operation. As a result, wake-up time is related to the time spent
in power-down mode, and shorter power-down cycles result in
proportionally shorter wake-up times.
06571-064
TOTAL POWER (W)
0.75
50
0.50
SAMPLE RATE (MSPS)
0.4
IAVDD
25
IAVDD
Figure 66. AD9627-80 Power and Current vs. Sample Rate
0.5
0
0.3
0
Figure 63. AD9627-150 Power and Current vs. Sample Rate
0.25
0.75
0
0.1
IDVDD
25
SAMPLE RATE (MSPS)
IDRVDD
SUPPLY CURRENT (A)
0.2
0.50
100
IDVDD
06571-063
TOTAL POWER (W)
0.3
TOTAL POWER
75
Figure 65. AD9627-105 Power and Current vs. Sample Rate
0.4
0.75
0
50
SUPPLY CURRENT (A)
0.5
25
06571-066
1.25
0
TOTAL POWER (W)
Reducing the capacitive load presented to the output drivers can
minimize digital power consumption. The data in Figure 63 was
taken using the same operating conditions as those used for the
Typical Performance Characteristics, with a 5 pF load on each
output driver.
0
0
This maximum current occurs when every output bit switches on
every clock cycle, that is, a full-scale square wave at the Nyquist
frequency of fCLK/2. In practice, the DRVDD current is
established by the average number of output bits switching,
which is determined by the sample rate and the characteristics
of the analog input signal.
0.25
0.2
0.25
where N is the number of output bits (26, in the case of the
AD9627, with the fast detect output pins disabled).
1.00
0.3
SUPPLY CURRENT (A)
POWER DISSIPATION AND STANDBY MODE
When using the SPI port interface, the user can place the ADC
in power-down mode or standby mode. Standby mode allows
the user to keep the internal reference circuitry powered when
faster wake-up times are required. See the Memory Map Register
Description section for more details.
Figure 64. AD9627-125 Power and Current vs. Sample Rate
Rev. B | Page 31 of 76
AD9627
DIGITAL OUTPUTS
Digital Output Enable Function (OEB)
The AD9627 output drivers can be configured to interface with
1.8 V to 3.3 V CMOS logic families by matching DRVDD to the
digital supply of the interfaced logic. The AD9627 can also be
configured for LVDS outputs using a DRVDD supply voltage
of 1.8 V.
The AD9627 has a flexible three-state ability for the digital output
pins. The three-state mode is enabled using the SMI SDO/OEB
pin or through the SPI interface. If the SMI SDO/OEB pin is low,
the output data drivers are enabled. If the SMI SDO/OEB pin is
high, the output data drivers are placed in a high impedance state.
This OEB function is not intended for rapid access to the data
bus. Note that OEB is referenced to the digital output driver supply
(DRVDD) and should not exceed that supply voltage.
In CMOS output mode, the output drivers are sized to provide
sufficient output current to drive a wide variety of logic families.
However, large drive currents tend to cause current glitches on
the supplies that may affect converter performance.
Applications requiring the ADC to drive large capacitive loads
or large fanouts may require external buffers or latches.
The output data format can be selected for either offset binary
or twos complement by setting the SCLK/DFS pin when operating
in the external pin mode (see Table 15).
As detailed in Application Note AN-877, Interfacing to High
Speed ADCs via SPI, the data format can be selected for offset
binary, twos complement, or gray code when using the SPI control.
Table 15. SCLK/DFS Mode Selection (External Pin Mode)
Voltage at Pin
AGND (default)
AVDD
SCLK/DFS
Offset binary
Twos complement
SDIO/DCS
DCS disabled
DCS enabled
When using the SPI interface, the data and fast detect outputs
of each channel can be independently three-stated by using the
output enable bar bit in Register 0x14.
TIMING
The AD9627 provides latched data with a pipeline delay of
12 clock cycles. Data outputs are available one propagation
delay (tPD) after the rising edge of the clock signal.
The length of the output data lines and loads placed on them
should be minimized to reduce transients within the AD9627.
These transients can degrade converter dynamic performance.
The lowest typical conversion rate of the AD9627 is 10 MSPS.
At clock rates below 10 MSPS, dynamic performance can degrade.
Data Clock Output (DCO)
The AD9627 provides two data clock output (DCO) signals
intended for capturing the data in an external register. The data
outputs are valid on the rising edge of DCO, unless the DCO clock
polarity has been changed via the SPI. See Figure 2 and Figure 3
for a graphical timing description.
Table 16. Output Data Format
Input (V)
VIN+ − VIN−
VIN+ − VIN−
VIN+ − VIN−
VIN+ − VIN−
VIN+ − VIN−
Condition (V)
< −VREF − 0.5 LSB
= −VREF
=0
= +VREF − 1.0 LSB
> +VREF − 0.5 LSB
Offset Binary Output Mode
0000 0000 0000
0000 0000 0000
1000 0000 0000
1111 1111 1111
1111 1111 1111
Rev. B | Page 32 of 76
Twos Complement Mode
1000 0000 0000
1000 0000 0000
0000 0000 0000
0111 1111 1111
0111 1111 1111
OR
1
0
0
0
1
AD9627
ADC OVERRANGE AND GAIN CONTROL
In receiver applications, it is desirable to have a mechanism to
reliably determine when the converter is about to be clipped.
The standard overflow indicator provides after-the-fact information on the state of the analog input that is of limited usefulness.
Therefore, it is helpful to have a programmable threshold below
full scale that allows time to reduce the gain before the clip
actually occurs. In addition, because input signals can have
significant slew rates, latency of this function is of major concern.
Highly pipelined converters can have significant latency. A good
compromise is to use the output bits from the first stage of the
ADC for this function. Latency for these output bits is very low,
and overall resolution is not highly significant. Peak input signals
are typically between full scale and 6 dB to 10 dB below full
scale. A 3-bit or 4-bit output provides adequate range and
resolution for this function.
Using the SPI port, the user can provide a threshold above which
an overrange output is active. As long as the signal is below that
threshold, the output should remain low. The fast detect outputs
can also be programmed via the SPI port so that one of the pins
functions as a traditional overrange pin for customers who
currently use this feature. In this mode, all 12 bits of the converter
are examined in the traditional manner, and the output is high for
the condition normally defined as overflow. In either mode, the
magnitude of the data is considered in the calculation of the
condition (but the sign of the data is not considered). The threshold
detection responds identically to positive and negative signals
outside the desired range (magnitude).
FAST DETECT OVERVIEW
The AD9627 contains circuitry to facilitate fast overrange detection, allowing very flexible external gain control implementations.
Each ADC has four fast detect (FD) output pins that are used
to output information about the current state of the ADC input
level. The function of these pins is programmable via the fast detect
mode select bits and the fast detect enable bits in Register 0x104,
allowing range information to be output from several points in
the internal datapath. These output pins can also be set up to
indicate the presence of overrange or underrange conditions,
according to programmable threshold levels. Table 17 shows the
six configurations available for the fast detect pins.
Table 17. Fast Detect Mode Select Bits Settings
Fast Detect
Mode Select Bits
(Register 0x104[3:1])
000
001
010
011
100
101
Information Presented on
Fast Detect (FD) Pins of Each ADC1, 2
FD[3]
FD[2]
FD[1] FD[0]
ADC fast magnitude
(see Table 18)
OR
ADC fast magnitude
(see Table 19)
OR
F_LT
ADC fast magnitude
(see Table 20)
C_UT F_LT
ADC fast magnitude
(see Table 20)
OR
C_UT
F_UT
F_LT
OR
F_UT
IG
DG
1
The fast detect pins are FD0A/FD0B to FD9A/FD9B for the CMOS mode
configuration and FD0+/FD0− to FD9+/FD9− for the LVDS mode
configuration.
2
See the ADC Overrange (OR) and Gain Switching sections for more
information about OR, C_UT, F_UT, F_LT, IG, and DG.
ADC FAST MAGNITUDE
When the fast detect output pins are configured to output the ADC
fast magnitude (that is, when the fast detect mode select bits are
set to 0b000), the information presented is the ADC level from
an early converter stage with a latency of only two clock cycles
(when in CMOS output mode). Using the fast detect output pins
in this configuration provides the earliest possible level indication
information. Because this information is provided early in the
datapath, there is significant uncertainty in the level indicated.
The nominal levels, along with the uncertainty indicated by the
ADC fast magnitude, are shown in Table 18.
Table 18. ADC Fast Magnitude Nominal Levels with Fast Detect
Mode Select Bits = 000
ADC Fast
Magnitude on
FD[3:0] Pins
0000
0001
0010
0011
0100
0101
0110
0111
1000
Rev. B | Page 33 of 76
Nominal Input
Magnitude
Below FS (dB)
<−24
−24 to −14.5
−14.5 to −10
−10 to −7
−7 to −5
−5 to −3.25
−3.25 to −1.8
−1.8 to −0.56
−0.56 to 0
Nominal Input
Magnitude
Uncertainty (dB)
Minimum to −18.07
−30.14 to −12.04
−18.07 to −8.52
−12.04 to −6.02
−8.52 to −4.08
−6.02 to −2.5
−4.08 to −1.16
−2.5 to FS
−1.16 to 0
AD9627
When the fast detect mode select bits are set to 0b001, 0b010, or
0b011, a subset of the fast detect output pins is available. In these
modes, the fast detect output pins have a latency of six clock cycles.
Table 19 shows the corresponding ADC input levels when the
fast detect mode select bits are set to 0b001 (that is, when ADC fast
magnitude is presented on the FD[3:1] pins).
Table 19. ADC Fast Magnitude Nominal Levels with
Fast Detect Mode Select Bits = 001
Nominal Input
Magnitude
Below FS (dB)
<−24
−24 to −14.5
−14.5 to −10
−10 to −7
−7 to −5
−5 to −3.25
−3.25 to −1.8
−1.8 to 0
ADC Fast Magnitude
on FD[3:1] Pins
000
001
010
011
100
101
110
111
Nominal Input
Magnitude
Uncertainty (dB)
Minimum to −18.07
−30.14 to −12.04
−18.07 to −8.52
−12.04 to −6.02
−8.52 to −4.08
−6.02 to −2.5
−4.08 to −1.16
−2.5 to 0
When the fast detect mode select bits are set to 0b010 or 0b011
(that is, when ADC fast magnitude is presented on the FD[3:2]
pins), the LSB is not provided. The input ranges for this mode
are shown in Table 20.
Nominal Input
Magnitude
Below FS (dB)
<−14.5
−14.5 to −7
−7 to −3.25
−3.25 to 0
The coarse upper threshold indicator is asserted if the ADC fast
magnitude input level is greater than the level programmed in
the coarse upper threshold register (Address 0x105[2:0]). This
value is compared with the ADC Fast Magnitude Bits[2:0]. The
coarse upper threshold output is output two clock cycles after the
level is exceeded at the input and, therefore, it provides a fast
indication of the input signal level. The coarse upper threshold
levels are shown in Table 21. This indicator remains asserted for
a minimum of two ADC clock cycles or until the signal drops
below the threshold level.
Table 21. Coarse Upper Threshold Levels
Coarse Upper Threshold
Register 0x105[2:0]
000
001
010
011
100
101
110
111
C_UT Is Active When Signal
Magnitude Below FS
Is Greater Than (dB)
<−24
−24
−14.5
−10
−7
−5
−3.25
−1.8
Fine Upper Threshold (F_UT)
Table 20. ADC Fast Magnitude Nominal Levels with
Fast Detect Mode Select Bits = 010 or 011
ADC Fast
Magnitude on
FD[2:1] Pins
00
01
10
11
Coarse Upper Threshold (C_UT)
Nominal Input
Magnitude
Uncertainty (dB)
Minimum to −12.04
−18.07 to −6.02
−8.52 to −2.5
−4.08 to 0
The fine upper threshold indicator is asserted if the input
magnitude exceeds the value programmed in the fine upper
threshold register located in Register 0x106 and Register 0x107.
The 13-bit threshold register is compared with the signal magnitude at the output of the ADC. This comparison is subject to the
ADC clock latency but is accurate in terms of the converter
resolution. The fine upper threshold magnitude is defined by
the following equation:
dBFS = 20 log(Threshold Magnitude/213)
ADC OVERRANGE (OR)
The ADC overrange indicator is asserted when an overrange is
detected on the input of the ADC. The overrange condition is
determined at the output of the ADC pipeline and, therefore, is
subject to a latency of 12 ADC clock cycles. An overrange at the
input is indicated by this bit 12 clock cycles after it occurs.
GAIN SWITCHING
The AD9627 includes circuitry that is useful in applications either
where large dynamic ranges exist or where gain ranging converters
are employed. This circuitry allows digital thresholds to be set
such that an upper threshold and a lower threshold can be
programmed. Fast detect mode select bit = 010 through fast
detect mode select bit = 101 support various combinations of the
gain switching options.
Fine Lower Threshold (F_LT)
The fine lower threshold indicator is asserted if the input
magnitude is less than the value programmed in the fine lower
threshold register located at Register 0x108 and Register 0x109.
The fine lower threshold register is a 13-bit register that is
compared with the signal magnitude at the output of the ADC.
This comparison is subject to ADC clock latency but is accurate
in terms of the converter resolution. The fine lower threshold
magnitude is defined by the following equation:
dBFS = 20 log(Threshold Magnitude/213)
The operation of the fine upper threshold indicators and fine
lower threshold indicators is shown in Figure 67.
One such use is to detect when an ADC is about to reach full
scale with a particular input condition. The result is to provide
an indicator that can be used to quickly insert an attenuator that
prevents ADC overdrive.
Rev. B | Page 34 of 76
AD9627
Increment Gain (IG) and Decrement Gain (DG)
with the magnitude at the output of the ADC. This comparison
is subject to the ADC clock latency but allows a finer, more
accurate comparison. The fine upper threshold magnitude is
defined by the following equation:
The increment gain and decrement gain indicators are intended
to be used together to provide information to enable external
gain control. The decrement gain indicator works in conjunction
with the coarse upper threshold bits, asserting when the input
magnitude is greater than the 3-bit value in the coarse upper
threshold register (Address 0x105). The increment gain indicator,
similarly, corresponds to the fine lower threshold bits, except
that it is asserted only if the input magnitude is less than the
value programmed in the fine lower threshold register after the
dwell time elapses. The dwell time is set by the 16-bit dwell time
value located at Address 0x10A and Address 0x10B and is set in
units of ADC input clock cycles ranging from 1 to 65,535. The
fine lower threshold register is a 13-bit register that is compared
dBFS = 20 log(Threshold Magnitude/213)
The decrement gain output works from the ADC fast detect
output pins, providing a fast indication of potential overrange
conditions. The increment gain uses the comparison at the
output of the ADC, requiring the input magnitude to remain
below an accurate, programmable level for a predefined period
before signaling external circuitry to increase the gain.
The operation of the increment gain output and the decrement
gain output is shown in Figure 67.
UPPER THRESHOLD (COARSE OR FINE)
DWELL TIME
TIMER RESET BY
RISE ABOVE F_LT
FINE LOWER THRESHOLD
DWELL TIME
C_UT OR F_UT*
TIMER COMPLETES BEFORE
SIGNAL RISES ABOVE F_LT
F_LT
DG
*C_UT AND F_UT DIFFER ONLY IN ACCURACY AND LATENCY.
NOTE: OUTPUTS FOLLOW THE INSTANTANEOUS SIGNAL LEVEL AND NOT THE ENVELOPE BUT ARE GUARANTEED ACTIVE FOR A MINIMUM OF 2 ADC CLOCK CYCLES.
Figure 67. Threshold Settings for C_UT, F_UT, IG, DG, and F_LT
Rev. B | Page 35 of 76
06571-067
IG
AD9627
SIGNAL MONITOR
The signal monitor result values can be obtained from the part by
reading back internal registers at Address 0x116 to Address 0x11B,
using the SPI port or the signal monitor SPORT output. The output
contents of the SPI-accessible signal monitor registers are set via
the two signal monitor mode bits of the signal monitor control
register. Both ADC channels must be configured for the same
signal monitor mode. Separate SPI-accessible, 20-bit signal monitor
result (SMR) registers are provided for each ADC channel. Any
combination of the signal monitor functions can also be output
to the user via the serial SPORT interface. These outputs are
enabled using the peak detector output enable, the rms magnitude
output enable, and the threshold crossing output enable bits in
the signal monitor SPORT control register.
For each signal monitor measurement, a programmable signal
monitor period register (SMPR) controls the duration of the
measurement. This time period is programmed as the number of
input clock cycles in a 24-bit signal monitor period register
located at Address 0x113, Address 0x114, and Address 0x115.
This register can be programmed with a period from 128 samples
to 16.78 (224) million samples.
Because the dc offset of the ADC can be significantly larger
than the signal of interest (affecting the results from the signal
monitor), a dc correction circuit is included as part of the signal
monitor block to null the dc offset before measuring the power.
PEAK DETECTOR MODE
The magnitude of the input port signal is monitored over a
programmable time period (determined by SMPR) to give the
peak value detected. This function is enabled by programming
a Logic 1 in the signal monitor mode bits of the signal monitor
control register or by setting the peak detector output enable bit
in the signal monitor SPORT control register. The 24-bit SMPR
must be programmed before activating this mode.
After enabling this mode, the value in the SMPR is loaded into
a monitor period timer and the countdown is started. The magnitude of the input signal is compared with the value in the internal
peak level holding register (not accessible to the user), and the
greater of the two is updated as the current peak level. The initial
value of the peak level holding register is set to the current ADC
input signal magnitude. This comparison continues until the
monitor period timer reaches a count of 1.
When the monitor period timer reaches a count of 1, the 13-bit
peak level value is transferred to the signal monitor holding register
(not accessible to the user), which can be read through the SPI port
or output through the SPORT serial interface. The monitor period
timer is reloaded with the value in the SMPR, and the countdown is
restarted. In addition, the magnitude of the first input sample is
updated in the peak level holding register, and the comparison and
update procedure, as explained previously, continues.
Figure 68 is a block diagram of the peak detector logic. The SMR
register contains the absolute magnitude of the peak detected by
the peak detector logic.
FROM
MEMORY
MAP
SIGNAL MONITOR
PERIOD REGISTER
DOWN
COUNTER
IS COUNT = 1?
LOAD
FROM
INPUT
PORTS
CLEAR
MAGNITUDE
STORAGE
REGISTER
LOAD
TO
MEMORY
SIGNAL MONITOR MAP/SPORT
HOLDING
REGISTER (SMR)
LOAD
COMPARE
A>B
06571-068
The signal monitor block provides additional information
about the signal being digitized by the ADC. The signal monitor
computes the rms input magnitude, the peak magnitude,
and/or the number of samples by which the magnitude exceeds
a particular threshold. Together, these functions can be used to
gain insight into the signal characteristics and to estimate the
peak/average ratio or even the shape of the complementary
cumulative distribution function (CCDF) curve of the input signal.
This information can be used to drive an AGC loop to optimize
the range of the ADC in the presence of real-world signals.
Figure 68. ADC Input Peak Detector Block Diagram
RMS/MS MAGNITUDE MODE
In this mode, the root-mean-square (rms) or mean-square (ms)
magnitude of the input port signal is integrated (by adding an
accumulator) over a programmable time period (determined by
SMPR) to give the rms or ms magnitude of the input signal.
This mode is set by programming Logic 0 in the signal monitor
mode bits of the signal monitor control register or by setting the
rms magnitude output enable bit in the signal monitor SPORT
control register. The 24-bit SMPR, representing the period over
which integration is performed, must be programmed before
activating this mode.
After enabling the rms/ms magnitude mode, the value in the SMPR
is loaded into a monitor period timer, and the countdown is started
immediately. Each input sample is converted to floating-point
format and squared. It is then converted to 11-bit, fixed-point
format and added to the contents of the 24-bit accumulator.
The integration continues until the monitor period timer reaches
a count of 1.
When the monitor period timer reaches a count of 1, the square
root of the value in the accumulator is taken and transferred,
after some formatting, to the signal monitor holding register, which
can be read through the SPI port or output through the SPORT
serial port. The monitor period timer is reloaded with the value
in the SMPR, and the countdown is restarted. In addition, the
first input sample signal power is updated in the accumulator,
and the accumulation continues with the subsequent input
samples.
Rev. B | Page 36 of 76
AD9627
Figure 69 illustrates the rms magnitude monitoring logic.
DOWN
COUNTER
IS COUNT = 1?
LOAD
CLEAR
ACCUMULATOR
TO
MEMORY
SIGNAL MONITOR MAP/SPORT
HOLDING
REGISTER (SMR)
LOAD
06571-069
FROM
INPUT
PORTS
Figure 69. ADC Input RMS Magnitude Monitoring Block Diagram
For rms magnitude mode, the value in the signal monitoring result
(SMR) register is a 20-bit fixed-point number. The following
equation can be used to determine the rms magnitude in dBFS
from the MAG value in the register. Note that if the signal monitor
period (SMP) is a power of 2, the second term in the equation
becomes 0.
MAG
SMP
RMS Magnitude = 20 log  20   10 log  ceillog 2 (SMP ) 
 2 
2

For ms magnitude mode, the value in the SMR is a 20-bit fixedpoint number. The following equation can be used to determine
the ms magnitude in dBFS from the MAG value in the register.
Note that if the SMP is a power of 2, the second term in the
equation becomes 0.
MAG
SMP
MS Magnitude = 10 log  20   10 log  ceillog 2 (SMP ) 
2
2




The monitor period timer is reloaded with the value in the SMPR
register, and the countdown is restarted. The internal count
register is also cleared to a value of 0. Figure 70 illustrates the
threshold crossing logic. The value in the SMR register is the
number of samples that have a magnitude greater than the
threshold register.
FROM
MEMORY
MAP
SIGNAL MONITOR
PERIOD REGISTER
DOWN
COUNTER
IS COUNT = 1?
LOAD
FROM
INPUT
PORTS
FROM
MEMORY
MAP
CLEAR
A COMPARE
A>B
COMPARE
A>B
TO
LOAD
MEMORY
SIGNAL MONITOR MAP/SPORT
HOLDING
REGISTER (SMR)
B
UPPER
THRESHOLD
REGISTER
06571-070
FROM
MEMORY
MAP
SIGNAL MONITOR
PERIOD REGISTER
When the monitor period timer reaches a count of 1, the value
in the internal count register is transferred to the signal monitor
holding register, which can be read through the SPI port or output
through the SPORT serial port.
Figure 70. ADC Input Threshold Crossing Block Diagram
ADDITIONAL CONTROL BITS
For additional flexibility in the signal monitoring process, two
control bits are provided in the signal monitor control register.
They are the signal monitor enable bit and the complex power
calculation mode enable bit.
Signal Monitor Enable Bit
THRESHOLD CROSSING MODE
In the threshold crossing mode of operation, the magnitude of
the input port signal is monitored over a programmable time
period (given by SMPR) to count the number of times it crosses
a certain programmable threshold value. This mode is set by
programming Logic 1x (where x is a don’t care bit) in the signal
monitor mode bits of the signal monitor control register or by
setting the threshold crossing output enable bit in the signal
monitor SPORT control register. Before activating this mode,
the user needs to program the 24-bit SMPR and the 13-bit
upper threshold register for each individual input port. The
same upper threshold register is used for both signal monitoring
and gain control (see the ADC Overrange and Gain Control
section).
After entering this mode, the value in the SMPR is loaded into
a monitor period timer, and the countdown is started. The magnitude of the input signal is compared with the upper threshold
register (programmed previously) on each input clock cycle.
If the input signal has a magnitude greater than the upper
threshold register, the internal count register is incremented by 1.
The initial value of the internal count register is set to 0. This
comparison and incrementing of the internal count register
continues until the monitor period timer reaches a count of 1.
The signal monitor enable bit, located in Bit 0 of Register 0x112,
enables operation of the signal monitor block. If the signal monitor
function is not needed in a particular application, this bit should
be cleared (default) to conserve power.
Complex Power Calculation Mode Enable Bit
When this bit is set, the part assumes that Channel A is digitizing
the I data and Channel B is digitizing the Q data for a complex
input signal (or vice versa). In this mode, the power reported is
equal to
I 2  Q2
This result is presented in the Signal Monitor DC Value Channel A
register if the signal monitor mode bits are set to 00. The Signal
Monitor DC Value Channel B register continues to compute the
Channel B value.
DC CORRECTION
Because the dc offset of the ADC may be significantly larger
than the signal being measured, a dc correction circuit is included
to null the dc offset before measuring the power. The dc correction
circuit can also be switched into the main signal path, but this
may not be appropriate if the ADC is digitizing a time-varying
signal with significant dc content, such as GSM.
Rev. B | Page 37 of 76
AD9627
DC Correction Bandwidth
SIGNAL MONITOR SPORT OUTPUT
The dc correction circuit is a high-pass filter with a programmable
bandwidth (ranging between 0.15 Hz and 1.2 kHz at 125 MSPS).
The bandwidth is controlled by writing the 4-bit dc correction
register located at Register 0x10C, Bits[5:2].
The following equation can be used to compute the bandwidth
value for the dc correction circuit:
f
DC _ Corr _ BW  2 k  14  CLK
2 
The SPORT is a serial interface with three output pins:
SMI SCLK (SPORT clock), SMI SDFS (SPORT frame sync), and
SMI SDO (SPORT data output). The SPORT is the master and
drives all three SPORT output pins on the chip.
SMI SCLK
where:
k is the 4 bit value programmed in Register 0x10C, Bits[5:2]
(values between 0 and 13 are valid for k; programming 14 or
15 provides the same result as programming 13).
fCLK is the AD9627 ADC sample rate in hertz (Hz).
DC Correction Readback
The current dc correction value can be read back in Register 0x10D
and Register 0x10E for Channel A and Register 0x10F and
Register 0x110 for Channel B. The dc correction value is a 12-bit
value that can span the entire input range of the ADC.
DC Correction Freeze
Setting Bit 6 of Register 0x10C freezes the dc correction at its
current state and continues to use the last updated value as the
dc correction value. Clearing this bit restarts dc correction and
adds the currently calculated value to the data.
The data and frame sync are driven on the positive edge of the
SMI SCLK. The SMI SCLK has three possible baud rates: 1/2, 1/4,
or 1/8 the ADC clock rate, based on the SPORT controls. The SMI
SCLK can also be gated off when not sending any data, based on
the SPORT SMI SCLK sleep bit. Using this bit to disable the SMI
SCLK when it is not needed can reduce any coupling errors back
into the signal path, if these prove to be a problem in the system.
Doing so, however, has the disadvantage of spreading the frequency
content of the clock. If desired, the SMI SCLK can be left running
to ease frequency planning.
SMI SDFS
The SMI SDFS is the serial data frame sync, and it defines the
start of a frame. One SPORT frame includes data from both
datapaths. The data from Datapath A is sent just after the frame
sync, followed by data from Datapath B.
SMI SDO
The SMI SDO is the serial data output of the block. The data
is sent MSB first on the next positive edge after the SMI SDFS.
Each data output block includes one or more rms magnitude, peak
level, and threshold crossing values from each datapath in the
stated order. If enabled, the data is sent, rms first, followed by peak
and threshold, as shown in Figure 71.
DC Correction Enable Bits
Setting Bit 0 of Register 0x10C enables dc correction for use in
the signal monitor calculations. The calculated dc correction
value can be added to the output data signal path by setting Bit 1
of Register 0x10C.
GATED, BASED ON CONTROL
SMI SCLK
SMI SDFS
MSB
PK CH A
RMS/MS CH A LSB
20 CYCLES
16 CYCLES
THR CH A
MSB
16 CYCLES
RMS/MS CH B LSB
20 CYCLES
PK CH B
16 CYCLES
THR CH B
RMS/MS CH A
06571-071
SMI SDO
16 CYCLES
Figure 71. Signal Monitor SPORT Output Timing (RMS, Peak, and Threshold Enabled)
GATED, BASED ON CONTROL
SMI SCLK
SMI SDFS
MSB
RMS/MS CH A LSB
20 CYCLES
THR CH A
16 CYCLES
MSB
RMS/MS CH B LSB
20 CYCLES
THR CH B
16 CYCLES
Figure 72. Signal Monitor SPORT Output Timing (RMS and Threshold Enabled)
Rev. B | Page 38 of 76
RMS/MS CH A
06571-072
SMI SDO
AD9627
BUILT-IN SELF-TEST (BIST) AND OUTPUT TEST
The AD9627 includes built-in test features designed to enable
verification of the integrity of each channel as well as facilitate
board level debugging. A BIST (built-in self-test) feature is included
that verifies the integrity of the digital datapath of the AD9627.
Various output test options are also provided to place predictable
values on the outputs of the AD9627.
BUILT-IN SELF-TEST (BIST)
The BIST is a thorough test of the digital portion of the selected
AD9627 signal path. When enabled, the test runs from an internal
pseudorandom noise (PN) source through the digital datapath
starting at the ADC block output. The BIST sequence runs for
512 cycles and stops. The BIST signature value for Channel A or
Channel B is placed in Register 0x24 and Register 0x25. If one
channel is chosen, its BIST signature is written to the two registers.
If both channels are chosen, the results from Channel A are placed
in the BIST signature registers.
The outputs are not disconnected during this test, so the PN
sequence can be observed as it runs. The PN sequence can be
continued from its last value or reset from the beginning, based
on the value programmed in Register 0x0E, Bit 2. The BIST
signature result varies based on the channel configuration.
OUTPUT TEST MODES
The output test options are shown in Table 25. When an output
test mode is enabled, the analog section of the ADC is disconnected from the digital back end blocks and the test pattern is run
through the output formatting block. Some of the test patterns are
subject to output formatting, and some are not. The seed value for
the PN sequence tests can be forced if the PN reset bits are used
to hold the generator in reset mode by setting Bit 4 or Bit 5 of
Register 0x0D. These tests can be performed with or without
an analog signal (if present, the analog signal is ignored), but
they do require an encode clock. For more information, see
Application Note AN-877, Interfacing to High Speed ADCs via SPI.
Rev. B | Page 39 of 76
AD9627
CHANNEL/CHIP SYNCHRONIZATION
The AD9627 has a SYNC input that offers the user flexible
synchronization options for synchronizing the internal blocks.
The clock divider sync feature is useful for guaranteeing synchronized sample clocks across multiple ADCs. The signal monitor
block can also be synchronized using the SYNC input, allowing
properties of the input signal to be measured during a specific
time period. The input clock divider can be enabled to synchronize
on a single occurrence of the SYNC signal or on every occurrence.
The signal monitor block is synchronized on every SYNC input
signal.
The SYNC input is internally synchronized to the sample clock;
however, to ensure there is no timing uncertainty between multiple
parts, the SYNC input signal should be externally synchronized to
the input clock signal, meeting the setup and hold times shown
in Table 8. The SYNC input should be driven using a singleended CMOS-type signal.
Rev. B | Page 40 of 76
AD9627
SERIAL PORT INTERFACE (SPI)
The AD9627 serial port interface (SPI) allows the user to configure
the converter for specific functions or operations through a
structured register space provided inside the ADC. The SPI
gives the user added flexibility and customization, depending on
the application. Addresses are accessed via the serial port and
can be written to or read from via the port. Memory is organized
into bytes that can be further divided into fields, which are documented in the Memory Map section. For detailed operational
information, see Application Note AN-877, Interfacing to High
Speed ADCs via SPI.
CONFIGURATION USING THE SPI
Three pins define the SPI of this ADC: the SCLK/DFS pin, the
SDIO/DCS pin, and the CSB pin (see Table 22). The SCLK/DFS
(a serial clock) is used to synchronize the read and write data
presented from and to the ADC. The SDIO/DCS (serial data
input/output) is a dual-purpose pin that allows data to be sent
and read from the internal ADC memory map registers. The
CSB (chip select bar) is an active-low control that enables or
disables the read and write cycles.
Table 22. Serial Port Interface Pins
Pin
SCLK
SDIO
CSB
Function
Serial Clock. The serial shift clock input, which is used to
synchronize serial interface reads and writes.
Serial Data Input/Output. A dual-purpose pin that
typically serves as an input or an output, depending on
the instruction being sent and the relative position in the
timing frame.
Chip Select Bar. An active-low control that gates the read
and write cycles.
The falling edge of the CSB, in conjunction with the rising edge
of the SCLK, determines the start of the framing. An example of
the serial timing and its definitions can be found in Figure 73
and Table 8.
Other modes involving the CSB are available. The CSB can be
held low indefinitely, which permanently enables the device;
this is called streaming. The CSB can stall high between bytes to
allow for additional external timing. When CSB is tied high, SPI
functions are placed in high impedance mode. This mode turns
on any SPI pin secondary functions.
During an instruction phase, a 16-bit instruction is transmitted.
Data follows the instruction phase, and its length is determined
by the W0 and W1 bits.
All data is composed of 8-bit words. The first bit of each individual
byte of serial data indicates whether a read command or a write
command is issued. This allows the serial data input/output
(SDIO) pin to change direction from an input to an output.
In addition to word length, the instruction phase determines
whetherthe serial frame is a read or write operation, allowing
the serial port to be used both to program the chip and to read
the contents of the on-chip memory. If the instruction is a readback
operation, performing a readback causes the serial data input/
output (SDIO) pin to change direction from an input to an output
at the appropriate point in the serial frame.
Data can be sent in MSB-first mode or in LSB-first mode. MSB
first is the default on power-up and can be changed via the SPI
port configuration register. For more information about this
and other features, see Application Note AN-877, Interfacing to
High Speed ADCs via SPI.
HARDWARE INTERFACE
The pins described in Table 22 comprise the physical interface
between the user programming device and the serial port of the
AD9627. The SCLK pin and the CSB pin function as inputs
when using the SPI interface. The SDIO pin is bidirectional,
functioning as an input during write phases and as an output
during readback.
The SPI interface is flexible enough to be controlled by either
FPGAs or microcontrollers. One method for SPI configuration
is described in detail in Application Note AN-812, MicrocontrollerBased Serial Port Interface (SPI) Boot Circuit.
The SPI port should not be active during periods when the full
dynamic performance of the converter is required. Because the
SCLK signal, the CSB signal, and the SDIO signal are typically
asynchronous to the ADC clock, noise from these signals can
degrade converter performance. If the on-board SPI bus is used for
other devices, it may be necessary to provide buffers between
this bus and the AD9627 to prevent these signals from transitioning at the converter inputs during critical sampling periods.
Some pins serve a dual function when the SPI interface is not
being used. When the pins are strapped to AVDD or ground
during device power-on, they are associated with a specific
function. The Digital Outputs section describes the strappable
functions supported on the AD9627.
Rev. B | Page 41 of 76
AD9627
CONFIGURATION WITHOUT THE SPI
SPI ACCESSIBLE FEATURES
In applications that do not interface to the SPI control registers,
the SDIO/DCS pin, the SCLK/DFS pin, the SMI SDO/OEB pin,
and the SMI SCLK/PDWN pin serve as standalone CMOScompatible control pins. When the device is powered up, it is
assumed that the user intends to use the pins as static control
lines for the duty cycle stabilizer, output data format, output
enable, and power-down feature control. In this mode, the CSB
chip select should be connected to AVDD, which disables the
serial port interface.
Table 24 provides a brief description of the general features that
are accessible via the SPI. These features are described in detail
in Application Note AN-877, Interfacing to High Speed ADCs via
SPI. The AD9627 part-specific features are described in detail
following Table 25, the external memory map register table.
Table 23. Mode Selection
Clock
Offset
External
Voltage
AVDD (default)
AGND
AVDD
AGND (default)
AVDD
AGND (default)
AVDD
Pin
SDIO/DCS
SCLK/DFS
SMI SDO/OEB
SMI SCLK/PDWN
AGND (default)
Feature Name
Mode
Configuration
Duty cycle stabilizer enabled
Duty cycle stabilizer disabled
Twos complement enabled
Offset binary enabled
Outputs in high impedance
Outputs enabled
Chip in power-down or
standby
Normal operation
tHIGH
tDS
tS
Table 24. Features Accessible Using the SPI
tDH
Test I/O
Output Mode
Output Phase
Output Delay
VREF
Description
Allows the user to set either power-down mode
or standby mode
Allows the user to access the DCS via the SPI
Allows the user to digitally adjust the
converter offset
Allows the user to set test modes to have
known data on output bits
Allows the user to set up outputs
Allows the user to set the output clock polarity
Allows the user to vary the DCO delay
Allows the user to set the reference voltage
tCLK
tH
tLOW
CSB
SCLK DON’T CARE
R/W
W1
W0
A12
A11
A10
A9
A8
A7
D5
D4
D3
D2
D1
D0
DON’T CARE
06571-073
SDIO DON’T CARE
DON’T CARE
Figure 73. Serial Port Interface Timing Diagram
Rev. B | Page 42 of 76
AD9627
MEMORY MAP
READING THE MEMORY MAP REGISTER TABLE
Logic Levels
Each row in the memory map register table has eight bit locations.
The memory map is roughly divided into four sections: the chip
configuration registers (Address 0x00 to Address 0x02); the
channel index and transfer registers (Address 0x05 and
Address 0xFF); the ADC functions registers, including setup,
control, and test (Address 0x08 to Address 0x25); and the digital
feature control registers (Address 0x100 to Address 0x11B).
An explanation of logic level terminology follows:
The memory map register table (see Table 25) documents the
default hexadecimal value for each hexadecimal address shown.
The column with the heading Bit 7 (MSB) is the start of the
default hexadecimal value given. For example, Address 0x18,
the VREF select register, has a hexadecimal default value of 0xC0.
This means that Bit 7 = 1, Bit 6 = 1, and the remaining bits are 0s.
This setting is the default reference selection setting. The default
value uses a 2.0 V p-p reference. For more information on this
function and others, see Application Note AN-877, Interfacing to
High Speed ADCs via SPI. This document details the functions
controlled by Register 0x00 to Register 0xFF. The remaining
registers, from Register 0x100 to Register 0x11B, are documented
in the Memory Map Register Description section.
Open Locations
All address and bit locations that are not included in Table 25
are not currently supported for this device. Unused bits of a
valid address location should be written with 0s. Writing to these
locations is required only when part of an address location is
open (for example, Address 0x18). If the entire address location
is open (for example, Address 0x13), this address location should
not be written.


“Bit is set” is synonymous with “bit is set to Logic 1” or
“writing Logic 1 for the bit.”
“Clear a bit” is synonymous with “bit is set to Logic 0” or
“writing Logic 0 for the bit.”
Transfer Register Map
Address 0x08 to Address 0x18 are shadowed. Writes to these
addresses do not affect part operation until a transfer command
is issued by writing 0x01 to Address 0xFF, setting the transfer bit.
This allows these registers to be updated internally and simultaneously when the transfer bit is set. The internal update takes
place when the transfer bit is set, and the bit autoclears.
Channel-Specific Registers
Some channel setup functions, such as the signal monitor
thresholds, can be programmed differently for each channel.
In these cases, channel address locations are internally duplicated
for each channel. These registers and bits are designated in Table 25
as local. These local registers and bits can be accessed by setting
the appropriate Channel A or Channel B bits in Register 0x05.
If both bits are set, the subsequent write affects the registers of
both channels. In a read cycle, only Channel A or Channel B
should be set to read one of the two registers. If both bits are set
during an SPI read cycle, the part returns the value for Channel A.
Registers and bits designated as global in Table 25 affect the
entire part or the channel features where independent settings are
not allowed between channels. The settings in Register 0x05 do
not affect the global registers and bits.
Default Values
After the AD9627 is reset, critical registers are loaded with
default values. The default values for the registers are given in
the memory map register table, Table 25.
Rev. B | Page 43 of 76
AD9627
MEMORY MAP REGISTER TABLE
All address and bit locations that are not included in Table 25 are not currently supported for this device.
Table 25. Memory Map Registers
Addr
Register
Bit 7
(Hex)
Name
(MSB)
Chip Configuration Registers
0x00
0
SPI Port
Configuration
(Global)
0x01
Chip ID
(Global)
0x02
Chip Grade
(Global)
Open
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(LSB)
LSB first
Soft reset
1
1
Soft reset
LSB first
0
8-bit Chip ID[7:0]
(AD9627 = 0x12)
(default)
Speed grade ID
Open
00 = 150 MSPS
01 = 125 MSPS
10 = 105 MSPS
11 = 80 MSPS
Open
Default
Value
(Hex)
Default
Notes/
Comments
0x18
The nibbles
are mirrored
so LSB-first
mode or MSBfirst mode
registers
correctly,
regardless of
shift mode
Read only
0x12
Open
Open
Open
Speed grade
ID used to
differentiate
devices; read
only
Channel Index and Transfer Registers
0x05
Channel Index
Open
Open
Open
Open
Open
Open
Data
Channel B
(default)
Data
Channel A
(default)
0x03
0xFF
Transfer
Open
Open
Open
Open
Open
Open
Open
Transfer
0x00
ADC Functions
0x08
Power Modes
Open
Open
Open
Open
Open
Internal power-down
mode (local)
00 = normal operation
01 = full power-down
10 = standby
11 = normal operation
0x00
0x09
Global Clock
(Global)
Open
Open
External
powerdown pin
function
(global)
0 = pdwn
1 = stndby
Open
Open
Open
Open
Open
0x01
0x0B
Clock Divide
(Global)
Open
Open
Open
Open
Open
0x0D
Test Mode
(Local)
Open
Open
Reset PN23
gen
Reset
PN9 gen
Open
Rev. B | Page 44 of 76
Duty cycle
stabilizer
(default)
Clock divide ratio
000 = divide by 1
001 = divide by 2
010 = divide by 3
011 = divide by 4
100 = divide by 5
101 = divide by 6
110 = divide by 7
111 = divide by 8
Output test mode
000 = off (default)
001 = midscale short
010 = positive FS
011 = negative FS
100 = alternating checkerboard
101 = PN 23 sequence
110 = PN 9 sequence
111 = one/zero word toggle
Bits are set
to determine
which device
on the chip
receives the
next write
command;
applies to local
registers only
Synchronously
transfers data
from the
master shift
register to the
slave
Determines
various generic
modes of chip
operation
0x00
Clock divide
values other
than 000
automatically
cause the duty
cycle stabilizer
to become
active
0x00
When this
register is set,
the test data
is placed on
the output
pins in place of
normal data
AD9627
Addr
(Hex)
0x0E
0x10
0x14
Register
Name
BIST Enable
(Local)
Offset Adjust
(Local)
Output Mode
Bit 7
(MSB)
Open
Bit 6
Open
Open
Open
Drive
strength
0 V to 3.3 V
CMOS or
ANSI
LVDS;
1 V to 1.8 V
CMOS or
reduced
LVDS
(global)
Invert DCO
clock
Output type
0 = CMOS
1 = LVDS
(global)
Open
Output
enable bar
(local)
Open
Open
Open
Open
Open
0x16
Clock Phase
Control
(Global)
0x17
DCO Output
Delay (Global)
Open
0x18
VREF Select
(Global)
Reference voltage selection
00 = 1.25 V p-p
01 = 1.5 V p-p
10 = 1.75 V p-p
11 = 2.0 V p-p (default)
Bit 5
Open
0x104
0x105
0x106
0x107
0x108
Fast Detect
Control (Local)
Coarse Upper
Threshold
(Local)
Fine Upper
Threshold
Register 0
(Local)
Fine Upper
Threshold
Register 1
(Local)
Fine Lower
Threshold
Register 0
(Local)
Bit 3
Open
Bit 2
Reset BIST
sequence
Bit 1
Open
Open
Open
Open
Output
invert
(local)
00 = offset binary
01 = twos complement
01 = gray code
11 = offset binary
(local)
Open
Input clock divider phase adjust
000 = no delay
001 = 1 input clock cycle
010 = 2 input clock cycles
011 = 3 input clock cycles
100 = 4 input clock cycles
101 = 5 input clock cycles
110 = 6 input clock cycles
111 = 7 input clock cycles
DCO clock delay
(delay = 2500 ps × register value/31)
00000 = 0 ps
00001 = 81 ps
00010 = 161 ps
…
11110 = 2419 ps
11111 = 2500 ps
Open
Open
Open
Open
Configures the
outputs and
the format of
the data
0x00
Allows
selection of
clock delays
into the input
clock divider
0x00
0xC0
Read only
BIST Signature[15:8]
0x00
Read only
Open
Open
Open
Open
Open
Open
Open
Open
Open
Open
Clock
Clock
divider
divider
next sync
sync
only
enable
Fast Detect Mode Select[2:0]
Open
Fine Upper Threshold[12:8]
Fine Lower Threshold[7:0]
Rev. B | Page 45 of 76
Master
sync
enable
Fast detect
enable
Coarse Upper Threshold[2:0]
Fine Upper Threshold[7:0]
Open
0x00
0x00
Open
Open
Default
Notes/
Comments
BIST Signature[7:0]
Signal
monitor
sync
enable
Open
Open
Default
Value
(Hex)
0x00
0x00
Offset adjust in LSBs from +31 to −32
(twos complement format)
0x24
BIST Signature
LSB (Local)
0x25
BIST Signature
MSB (Local)
Digital Feature Control
0x100
Sync Control
(Global)
Bit 4
Open
Bit 0
(LSB)
BIST enable
0x00
0x00
0x00
0x00
0x00
0x00
AD9627
Addr
(Hex)
0x109
0x10A
0x10B
0x10C
0x10D
0x10E
0x10F
0x110
0x111
Register
Name
Fine Lower
Threshold
Register 1
(Local)
Increase Gain
Dwell Time
Register 0
(Local)
Increase Gain
Dwell Time
Register 1
(Local)
Signal Monitor
DC Correction
Control
(Global)
Signal Monitor
DC Value
Channel A
Register 0
(Global)
Signal Monitor
DC Value
Channel A
Register 1
(Global)
Signal Monitor
DC Value
Channel B
Register 0
(Global)
Signal Monitor
DC Value
Channel B
Register 1
(Global)
Signal Monitor
SPORT Control
(Global)
0x112
Signal Monitor
Control
(Global)
0x113
Signal Monitor
Period
Register 0
(Global)
Signal Monitor
Period
Register 1
(Global)
Signal Monitor
Period
Register 2
(Global)
Signal Monitor
Result
Channel A
Register 0
(Global)
0x114
0x115
0x116
Bit 7
(MSB)
Open
Open
Bit 6
Open
Bit 5
Open
Default
Value
(Hex)
0x00
Default
Notes/
Comments
Increase Gain Dwell Time[7:0]
0x00
In ADC clock
cycles
Increase Gain Dwell Time[15:8]
0x00
In ADC clock
cycles
Bit 4
Bit 3
Bit 2
Bit 1
Fine Lower Threshold[12:8]
DC Correction Bandwidth[3:0]
DC
correction
freeze
DC
correction
for signal
path
enable
Bit 0
(LSB)
DC
correction
for signal
monitor
enable
0x00
DC Value Channel A[7:0]
Open
Open
Read only
DC Value Channel A[13:8]
Read only
DC Value Channel B[7:0]
Open
Open
Open
RMS/MS
magnitude
output
enable
Peak
detector
output
enable
Complex
power
calculation
mode
enable
Open
Open
Read only
DC Value Channel B[13:8]
Threshold
crossing
output
enable
SPORT SMI
SPORT
SCLK divide
SMI SCLK
sleep
00 = undefined
01 = divide by 2
10 = divide by 4
11 = divide by 8
Open
Signal monitor mode
Signal
monitor 00 = rms/ms magnitude
rms/ms
01 = peak detector
select
10 = threshold crossing
0 = rms
11 = threshold crossing
1 = ms
Signal Monitor Period[7:0]
Read only
Signal
monitor
SPORT
output
enable
0x04
Signal
monitor
enable
0x00
0x80
In ADC clock
cycles
Signal Monitor Period[15:8]
0x00
In ADC clock
cycles
Signal Monitor Period[23:16]
0x00
In ADC clock
cycles
Signal Monitor Result Channel A[7:0]
Rev. B | Page 46 of 76
Read only
AD9627
Addr
(Hex)
0x117
0x118
0x119
0x11A
0x11B
Register
Name
Signal Monitor
Result
Channel A
Register 1
(Global)
Signal Monitor
Result
Channel A
Register 2
(Global)
Signal Monitor
Result
Channel B
Register 0
(Global)
Signal Monitor
Result
Channel B
Register 1
(Global)
Signal Monitor
Result
Channel B
Register 2
(Global)
Bit 7
(MSB)
Bit 6
Bit 5
Open
Open
Open
Open
Open
Bit 4
Bit 3
Bit 2
Signal Monitor Result Channel A[15:8]
Open
Bit 1
Bit 0
(LSB)
Default
Value
(Hex)
Signal Monitor Value Channel A[19:16]
Default
Notes/
Comments
Read only
Read only
Signal Monitor Result Channel B[7:0]
Read only
Signal Monitor Result Channel B[15:8]
Read only
Open
Open
Signal Monitor Result Channel B[19:16]
Read only
MEMORY MAP REGISTER DESCRIPTIONS
Bit 0—Fast Detect Enable
For additional information about functions controlled in
Register 0x00 to Register 0xFF, see Application Note AN-877,
Interfacing to High Speed ADCs via SPI.
Bit 0 is used to enable the fast detect output pins. When the fast
detect output pins are disabled, the outputs go into a high
impedance state. In LVDS mode, when the outputs are
interleaved, the outputs go high-Z only if both channels are
turned off (power-down/standby/output disabled). If only one
channel is turned off (power-down/standby/output disabled), the
fast detect output pins repeat the data of the active channel.
Sync Control (Register 0x100)
Bit 7—Signal Monitor Sync Enable
Bit 7 enables the sync pulse from the external SYNC input to
the signal monitor block. The sync signal is passed when Bit 7
and Bit 0 are high. This is continuous sync mode.
Bits[6:3]—Reserved
Coarse Upper Threshold (Register 0x105)
Bits[7:3]—Reserved
Bits[2:0]—Coarse Upper Threshold
Bit 2—Clock Divider Next Sync Only
If the master sync enable bit (Address 0x100, Bit0) and the clock
divider sync enable bit (Address 0x100, Bit 1) are high, Bit 2 allows
the clock divider to sync to the first sync pulse it receives and to
ignore the rest. The clock divider sync enable bit (Address 0x100,
Bit 1) resets after it syncs.
These bits set the level required to assert the coarse upper
threshold indication (see Table 21).
Fine Upper Threshold (Register 0x106 and Register 0x107)
Register 0x106, Bits[7:0]—Fine Upper Threshold[7:0]
Register 0x107, Bits[7:5]—Reserved
Bit 1—Clock Divider Sync Enable
Register 0x107, Bits[4:0]—Fine Upper Threshold[12:8]
Bit 1 gates the sync pulse to the clock divider. The sync signal is
passed when Bit 1 is high and Bit 0 is high. This is continuous
sync mode.
These registers provide the fine upper limit threshold. This 13-bit
value is compared with the 13-bit magnitude from the ADC block.
If the ADC magnitude exceeds this threshold value, the F_UT
flag is set.
Bit 0—Master Sync Enable
Fine Lower Threshold (Register 0x108 and Register 0x109)
Register 0x108, Bits[7:0]—Fine Lower Threshold[7:0]
Bit 0 must be high to enable any of the sync functions.
Fast Detect Control (Register 0x104)
Bits[7:4]—Reserved
Register 0x109, Bits[7:5]—Reserved
Register 0x109, Bits[4:0]—Fine Lower Threshold[12:8]
Bits[3:1]—Fast Detect Mode Select
These bits set the mode of the fast detect output pins (see Table 17).
These registers provide the fine lower limit threshold. This 13-bit
value is compared with the 13-bit magnitude from the ADC
block. If the ADC magnitude is less than this threshold value,
the F_LT flag is set.
Rev. B | Page 47 of 76
AD9627
Increase Gain Dwell Time (Register 0x10A and
Register 0x10B)
Register 0x10A, Bits[7:0]—Increase Gain Dwell Time[7:0]
Register 0x10B, Bits[7:0]—Increase Gain Dwell Time[15:8]
These registers are programmed with the dwell time in ADC
clock cycles for which the signal must be below the fine lower
threshold value before the increase gain output is asserted.
Signal Monitor SPORT Control (Register 0x111)
Bit 7—Reserved
Bit 6—RMS/MS Magnitude Output Enable
These bits enable the 20-bit rms or ms magnitude measurement
as output on the SPORT.
Bit 5—Peak Detector Output Enable
Signal Monitor DC Correction Control (Register 0x10C)
Bit 7—Reserved
Bit 6—DC Correction Freeze
Bit 5 enables the 13-bit peak measurement as output on the
SPORT.
When Bit 6 is set high, the dc correction is no longer updated
to the signal monitor block. It holds the last dc value it calculated.
Bit 4 enables the 13-bit threshold measurement as output on
the SPORT.
Bits[5:2]—DC Correction Bandwidth
Bits[3:2]—SPORT SMI SCLK Divide
These bits set the averaging time of the power monitor dc
correction function. This 4-bit word sets the bandwidth of the
correction block according to the following equation:
The values of these bits set the SPORT SMI SCLK divide ratio
from the input clock. A value of 0x01 sets divide by 2 (default),
a value of 0x10 sets divide by 4, and a value of 0x11 sets divide by 8.
DC _ Corr _ BW  2 k  14 
Bit 4—Threshold Crossing Output Enable
Bit 1— SPORT SMI SCLK Sleep
fCLK
2 
Setting Bit 1 high causes the SMI SCLK to remain low when the
signal monitor block has no data to transfer.
where:
k is the 4 bit value programmed in Register 0x10C, Bits[5:2]
(values between 0 and 13 are valid for k; programming 14 or
15 provides the same result as programming 13).
fCLK is the AD9627 ADC sample rate in hertz (Hz).
Bit 0—Signal Monitor SPORT Output Enable
When set, Bit 0 enables the SPORT output of the signal monitor
to begin shifting out the result data from the signal monitor block.
Bit 1—DC Correction for Signal Path Enable
Signal Monitor Control (Register 0x112)
Bit 7—Complex Power Calculation Mode Enable
Setting Bit 1 high causes the output of the dc measurement
block to be summed with the data in the signal path to remove
the dc offset from the signal path.
This mode assumes I data is present on one channel and Q data
is present on the alternate channel. The result reported is the
complex power, measured as
Bit 0—DC Correction for Signal Monitor Enable
Bit 0 enables the dc correction function in the signal monitor block.
The dc correction is an averaging function that can be used by
the signal monitor to remove dc offset in the signal. Removing
this dc offset from the measurement allows a more accurate
reading.
Signal Monitor DC Value Channel A (Register 0x10D and
Register 0x10E)
Register 0x10D, Bits[7:0]—DC Value Channel A[7:0]
Register 0x10E, Bits[7:6]—Reserved
Register 0x10E, Bits[5:0]—DC Value Channel A[13:8]
These read-only registers hold the latest dc offset value computed
by the signal monitor for Channel A.
Signal Monitor DC Value Channel B (Register 0x10F and
Register 0x110)
Register 0x10F, Bits[7:0]—DC Value Channel B[7:0]
I 2  Q2
Bits[6:4]—Reserved
Bit 3—Signal Monitor RMS/MS Select
Setting Bit 3 low selects rms power measurement mode. Setting
Bit 3 high selects ms power measurement mode.
Bits[2:1]—Signal Monitor Mode
Bit 2 and Bit 1 set the mode of the signal monitor for data output
to Register 0x116 through Register 0x11B. Setting Bit 2 and Bit 1
to 0x00 selects rms/ms magnitude output; setting these bits to
0x01 selects peak detector output; and setting these bits to 0x10
or 0x11 selects threshold crossing output.
Bit 0—Signal Monitor Enable
Setting Bit 0 high enables the signal monitor block.
Register 0x110, Bits[7:6]—Reserved
Register 0x110, Bits[5:0]—DC Value Channel B[13:8]
These read-only registers hold the latest dc offset value computed
by the signal monitor for Channel B.
Rev. B | Page 48 of 76
AD9627
Signal Monitor Period (Register 0x113 to Register 0x115)
Register 0x113, Bits[7:0]—Signal Monitor Period[7:0]
Register 0x114, Bits[7:0]—Signal Monitor Period[15:8]
Register 0x115, Bits[7:0]—Signal Monitor Period[23:16]
This 24-bit value sets the number of clock cycles over which the
signal monitor performs its operation. The minimum value for
this register is 128 cycles; programmed values less than 128 revert
to 128.
Signal Monitor Result Channel A (Register 0x116 to
Register 0x118)
Register 0x116, Bits[7:0]—Signal Monitor Result
Channel A[7:0]
Signal Monitor Result Channel B (Register 0x119 to
Register 0x11B)
Register 0x119, Bits[7:0]— Signal Monitor Result
Channel B[7:0]
Register 0x11A, Bits[7:0]—Signal Monitor Result
Channel B[15:8]
Register 0x11B, Bits[7:4]—Reserved
Register 0x11B, Bits[3:0]—Signal Monitor Result
Channel B[19:16]
This 20-bit value contains the result calculated by the signal
monitoring block for Channel B. The result is dependent on the
settings in Register 0x112[2:1].
Register 0x117, Bits[7:0]—Signal Monitor Result
Channel A[15:8]
Register 0x118, Bits[7:4]—Reserved
Register 0x118, Bits[3:0]—Signal Monitor Result
Channel A[19:16]
This 20-bit value contains the result calculated by the signal
monitoring block for Channel A. The result is dependent on the
settings in Register 0x112[2:1].
Rev. B | Page 49 of 76
AD9627
APPLICATIONS INFORMATION
DESIGN GUIDELINES
Before starting design and layout of the AD9627 as a system,
it is recommended that the designer become familiar with these
guidelines, which discuss the special circuit connections and
layout requirements needed for certain pins.
Power and Ground Recommendations
When connecting power to the AD9627, it is recommended
that two separate 1.8 V supplies be used: one supply should be
used for analog (AVDD) and digital (DVDD), and a separate
supply should be used for the digital outputs (DRVDD). The
AVDD and DVDD supplies, while derived from the same source,
should be isolated with a ferrite bead or filter choke and separate
decoupling capacitors. The designer can employ several different
decoupling capacitors to cover both high and low frequencies.
These capacitors should be located close to the point of entry
at the PC board level and close to the pins of the part with
minimal trace length.
The copper plane should have several vias to achieve the lowest
possible resistive thermal path for heat dissipation to flow through
the bottom of the PCB. These vias should be filled or plugged with
nonconductive epoxy.
To maximize the coverage and adhesion between the ADC and
the PCB, a silkscreen should be overlaid to partition the continuous
plane on the PCB into several uniform sections. This provides
several tie points between the ADC and the PCB during the reflow
process. Using one continuous plane with no partitions guarantees
only one tie point between the ADC and the PCB. See the evaluation board for a PCB layout example. For detailed information
about packaging and PCB layout of chip scale packages, see
Application Note AN-772, A Design and Manufacturing Guide
for the Lead Frame Chip Scale Package (LFCSP).
CML
The CML pin should be decoupled to ground with a 0.1 μF
capacitor, as shown in Figure 47.
A single PCB ground plane should be sufficient when using the
AD9627. With proper decoupling and smart partitioning of the
PCB analog, digital, and clock sections, optimum performance
is easily achieved.
RBIAS
LVDS Operation
Reference Decoupling
The AD9627 defaults to CMOS output mode on power-up.
If LVDS operation is desired, this mode must be programmed
using the SPI configuration registers after power-up. When the
AD9627 powers up in CMOS mode with LVDS termination
resistors (100 Ω) on the outputs, the DRVDD current can be
higher than the typical value until the part is placed in LVDS
mode. This additional DRVDD current does not cause damage
to the AD9627, but it should be taken into account when considering the maximum DRVDD current for the part.
The VREF pin should be externally decoupled to ground with
a low ESR, 1.0 μF capacitor in parallel with a low ESR, 0.1 μF
ceramic capacitor.
To avoid this additional DRVDD current, the AD9627 outputs
can be disabled at power-up by taking the OEB pin high. After
the part is placed into LVDS mode via the SPI port, the OEB
pin can be taken low to enable the outputs.
The AD9627 requires that a 10 kΩ resistor be placed between
the RBIAS pin and ground. This resistor sets the master current
reference of the ADC core and should have at least a 1% tolerance.
SPI Port
The SPI port should not be active during periods when the full
dynamic performance of the converter is required. Because the
SCLK, CSB, and SDIO signals are typically asynchronous to the
ADC clock, noise from these signals can degrade converter
performance. If the on-board SPI bus is used for other devices,
it may be necessary to provide buffers between this bus and the
AD9627 to keep these signals from transitioning at the converter
inputs during critical sampling periods.
Exposed Paddle Thermal Heat Slug Recommendations
It is mandatory that the exposed paddle on the underside of the
ADC be connected to analog ground (AGND) to achieve the
best electrical and thermal performance. A continuous, exposed
(no solder mask), copper plane on the PCB should mate to the
AD9627 exposed paddle, Pin 0.
Rev. B | Page 50 of 76
AD9627
EVALUATION BOARD
The AD9627 evaluation board provides all of the support circuitry
required to operate the ADC in its various modes and configurations. The converter can be driven differentially through a double
balun configuration (default) or optionally through the AD8352
differential driver. The ADC can also be driven in a single-ended
fashion. Separate power pins are provided to isolate the DUT
from the AD8352 drive circuitry. Each input configuration can
be selected by proper connection of various components (see
Figure 75 to Figure 92). Figure 74 shows the typical bench
characterization setup used to evaluate the ac performance of
the AD9627.
External supplies can be used to operate the evaluation board
by removing L1, L3, L4, and L13 to disconnect the voltage
regulators supplied from the switching power supply. This enables
the user to individually bias each section of the board. Use P3
and P4 to connect a different supply for each section. At least
one 1.8 V supply is needed with a 1 A current capability for
AVDD and DVDD; a separate 1.8 V to 3.3 V supply is recommended for DRVDD. To operate the evaluation board using the
AD8352 option, a separate 5.0 V supply (AMP VDD) with
a 1 A current capability is needed. To operate the evaluation board
using the alternate SPI options, a separate 3.3 V analog supply
(VS) is needed, in addition to the other supplies. The 3.3 V
supply (VS) should have a 1 A current capability, as well. Solder
Jumper SJ35 allows the user to separate AVDD and DVDD,
if desired.
It is critical that the signal sources used for the analog input and
clock have very low phase noise (<<1 ps rms jitter) to realize the
optimum performance of the converter. Proper filtering of the
analog input signal to remove harmonics and lower the integrated
or broadband noise at the input is also necessary to achieve the
specified noise performance.
INPUT SIGNALS
When connecting the clock and analog source, use clean signal
generators with low phase noise, such as the Rohde & Schwarz
SMA100A signal generators or the equivalent. Use 1 m long,
shielded, RG-58, 50 Ω coaxial cable for making connections to the
evaluation board. Enter the desired frequency and amplitude for
the ADC. The AD9627 evaluation board from Analog Devices,
Inc., can accept a ~2.8 V p-p or 13 dBm sine wave input for the
clock. When connecting the analog input source, it is recommended that a multipole, narrow-band, band-pass filter with 50 Ω
terminations be used. Band-pass filters of this type are available
from TTE, Allen Avionics, and K&L Microwave, Inc. Connect the
filter directly to the evaluation board, if possible.
See Figure 75 to Figure 79 for the complete schematics and
layout diagrams that demonstrate the routing and grounding
techniques that should be applied at the system level.
POWER SUPPLIES
This evaluation board comes with a wall-mountable switching
power supply that provides a 6 V, 2 A maximum output. Connect
the supply to the rated 100 V ac to 240 V ac wall outlet at 47 Hz
to 63 Hz. The output of the supply is a 2.1 mm inner diameter
circular jack that connects to the PCB at J16. Once on the PC
board, the 6 V supply is fused and conditioned before connection
to six low dropout linear regulators that supply the proper bias
to each of the various sections on the board.
OUTPUT SIGNALS
The parallel CMOS outputs interface directly with the Analog
Devices standard ADC data capture board (HSC-ADC-EVALCZ).
For more information on the ADC data capture boards and their
optional settings, visit www.analog.com/FIFO.
WALL OUTLET
100V TO 240V AC
47Hz TO 63Hz
–
+
GND
VCP
AD9627
EVALUATION BOARD
12-BIT
PARALLEL
CMOS
12-BIT
PARALLEL
CMOS
CLK
SPI
Figure 74. Evaluation Board Connection
Rev. B | Page 51 of 76
HSC-ADC-EVALCZ
FPGA BASED
DATA
CAPTURE BOARD
USB
CONNECTION
SPI
PC RUNNING
VISUAL ANALOG
AND SPI
CONTROLLER
SOFTWARE
06571-074
ROHDE & SCHWARZ,
SMA100A,
2V p-p SIGNAL
SYNTHESIZER
+
VS
AINB
3.3V
–
GND
BAND-PASS
FILTER
3.3V
+
DRVDD IN
ROHDE & SCHWARZ,
SMA100A,
2V p-p SIGNAL
SYNTHESIZER
3.3V
–
GND
AINA
–
GND
BAND-PASS
FILTER
+
AMP VDD
ROHDE & SCHWARZ,
SMA100A,
2V p-p SIGNAL
SYNTHESIZER
1.8V
+
–
GND
5.0V
SWITCHING
POWER
SUPPLY
AVDD IN
6V DC
2A MAX
AD9627
DEFAULT OPERATION AND JUMPER SELECTION
SETTINGS
The following is a list of the default and optional settings or
modes allowed on the AD9627 evaluation board.
POWER
Connect the switching power supply that is provided in the
evaluation kit between a rated 100 V ac to 240 V ac wall outlet
at 47 Hz to 63 Hz and P500.
VIN
The evaluation board is set up for a double balun configuration
analog input with optimum 50 Ω impedance matching from
70 MHz to 200 MHz. For more bandwidth response, the differential capacitor across the analog inputs can be changed or
removed (see Table 13). The common mode of the analog inputs
is developed from the center tap of the transformer via the CML
pin of the ADC (see the Analog Input Considerations section).
VREF
VREF is set to 1.0 V by tying the SENSE pin to ground by adding
a jumper on Header J5 (Pin 1 to Pin 2). This causes the ADC to
operate in 2.0 V p-p full-scale range. To place the ADC in 1.0 V p-p
mode (VREF = 0.5 V), a jumper should be placed on Header J4.
A separate external reference option is also included on the evaluation board. To use an external reference, connect J6 (Pin 1 to Pin 2)
and provide an external reference at TP5. Proper use of the VREF
options is detailed in the Voltage Reference section.
RBIAS
RBIAS requires a 10 kΩ resistor (R503) to ground and is used to
set the ADC core bias current.
CLOCK
The default clock input circuitry is derived from a simple baluncoupled circuit using a high bandwidth 1:1 impedance ratio balun
(T5) that adds a very low amount of jitter to the clock path. The
clock input is 50 Ω terminated and ac-coupled to handle singleended sine wave inputs. The transformer converts the single-ended
input to a differential signal that is clipped before entering the
ADC clock inputs. When the AD9627 input clock divider is
utilized, clock frequencies up to 625 MHz can be input into the
evaluation board through Connector S5.
PDWN
To enable the power-down feature, connect J7, shorting the
PDWN pin to AVDD.
CSB
The CSB pin is internally pulled up, setting the chip into
external pin mode, to ignore the SDIO and SCLK information.
To connect the control of the CSB pin to the SPI circuitry on the
evaluation board, connect J21, Pin 1 to J21, Pin 2.
SCLK/DFS
If the SPI port is in external pin mode, the SCLK/DFS pin sets the
data format of the outputs. If the pin is left floating, the pin is internally pulled down, setting the default data format condition to
offset binary. Connecting J2, Pin 1 to J2, Pin 2 sets the format to
twos complement. If the SPI port is in serial pin mode, connecting
J2, Pin 2 to J2, Pin 3 connects the SCLK pin to the on-board SPI
circuitry (see the Serial Port Interface (SPI) section).
SDIO/DCS
If the SPI port is in external pin mode, the SDIO/DCS pin sets
the duty cycle stabilizer. If the pin is left floating, the pin is
internally pulled up, setting the default condition to DCS enabled.
To disable the DCS, connect J1, Pin 1 to J1, Pin 2. If the SPI port
is in serial pin mode, connecting J1, Pin 2 to J1, Pin 3 connects
the SDIO pin to the on-board SPI circuitry (see the Serial Port
Interface (SPI) section).
ALTERNATIVE CLOCK CONFIGURATIONS
Two alternate clocking options are provided on the AD9627
evaluation board. The first option is to use an on-board crystal
oscillator (Y1) to provide the clock input to the part. To enable
this crystal, Resistor R8 (0 Ω) and Resistor R85 (10 kΩ) should
be installed, and Resistor R82 and Resistor R30 should be removed.
A second clock option is to use a differential LVPECL clock to
drive the ADC input using the AD9516 (U2). When using this
drive option, the AD9516 charge pump filter components need
to be populated (see Figure 79). Consult the AD9516 data sheet
for more information.
To configure the clock input from S5 to drive the AD9516
reference input instead of directly driving the ADC, the
following components need to be added, removed, and/or
changed.
1.
Remove R32, R33, R99, and R101 in the default
clock path.
2.
Populate C78 and C79 with 0.001 μF capacitors and
R78 and R79 with 0 Ω resistors in the clock path.
In addition, unused AD9516 outputs (one LVDS and one LVPECL)
are routed to optional Connector S8 through Connector S11 on
the evaluation board.
Rev. B | Page 52 of 76
AD9627
ALTERNATIVE ANALOG INPUT DRIVE
CONFIGURATION
1.
Remove C1, C17, C18, and C117 in the default analog
input path.
This section provides a brief description of the alternative
analog input drive configuration using the AD8352. When
using this particular drive option, some additional components
need to be populated. For more details on the AD8352 differential
driver, including how it works and its optional pin settings,
consult the AD8352 data sheet.
2.
Populate C8 and C9 with 0.1 μF capacitors in the analog
input path. To drive the AD8352 in the differential input
mode, populate the T10 transformer; the R1, R37, R39,
R126, and R127 resistors; and the C10, C11, and C125
capacitors.
3.
Populate the optional amplifier output path with the
desired components including an optional low-pass filter.
Install 0 Ω resistors, R44 and R48. R43 and R47 should be
increased (typically to 100 Ω) to increase to 200 Ω the
output impedance seen by the AD8352.
To configure the analog input to drive the AD8352 instead of
the default transformer option, the following components need
to be added, removed, and/or changed for Channel A. For
Channel B the corresponding components should be changed.
Rev. B | Page 53 of 76
AIN+
AIN-
S1
2
S2
1
R28
1
0 OHM
R121
RES0402
0 OHM
R120
57.6 OHM
R1
57.6 OHM
INA+
0.1U
C117
0.1U
C1
R2
INA+
0 OHM
0.1U
C47
INA-
0.1U
C9
T10
0 OHM
R54
P
3
S 2
1
DNP
R36
5
4
5
4
S
ETC1-1-13
P
T1
1
2
3
1ADT1_1W
6T
2
3
T7
0 OHM
R110
CML
1
2
3
P
ETC1-1-13
S
T2
5
4
0.1U
C18
0.1U
C17
DEFAULT AMPLIFIER INPUT PAT H
4
5
ETC1-1-13
F
0.1U
R31
R29
R35
0 OHM
24.9 OHM
24.9 OHM
C8
4.12K
0.1U
C11
0.1U
C10
R126
INA-
F
0 OHM
R48
0 OHM
R44
C125
.3PF
DNP
R38
0 OHM
R37
100 OHM
CML
R42
4
3
2
1
VIN
RDN
RGN
RGP
R40
5
16
VIP
RDP
0 OHM
AMP+A
AMP-A
0 OHM
R39
R127
6
ENB
15
B
W1
A
7
GND
Z1
C3
0.1U
9
10
11
12
C22
0.1U
GND
VON
VCC
8
GND
VOP
VCC
13
AD8352
VCM
14
AMPVDD
R41
R5
10KOHM
R43
R47
10K OHM
57.6 OHM
OPTIONAL AMPL IFIER INPUT PATH
R4
Figure 75. Evaluation Board Schematic, Channel A Analog Inputs
2
F
0 OHM
33 OHM
33 OHM
Rev. B | Page 54 of 76
33 OHM
R27
33 OHM
R26
C23
0.1U
C27
10U
0.001U
C16
0.001U
C12
AMPVDD
C2
0.1U
C5
4.7PF
120NH
DNP
120NH
DNP
2
2
L16
0 OHM
R49
180NH
DNP
180NH
DNP
0 OHM
R50
VIN+A
TP15
1
VIN-A
TP1
1 4
L17 1
IND0603
C4
18PF
DNP
1
IND0603
2
2
AVDD
AVDD
AMP+A
C139
12PF
DNP
AMP-A
Transformer/amp channel A
L15 1
IND0603
L14 1
IND0603
06571-075
AMPVDD
AD9627
SCHEMATICS
Figure 76. Evaluation Board Schematic, Channel B Analog Inputs
AIN+
AIN-
S4
S3
1
1
57.6 OHM
R52
57.6 OHM
R51
0 OHM
RES0402
R123
0 OHM
RES0402
R122
INB0.1U
C31
INB+
0.1U
C6
0.1U
C28
0 OHM
R67
INB-
4
5
S
3
2
1
DNP
0.1U
0.1U
C39
.3PF
C128
0.1U
4
5
T8
4
5
6
P
T3
S
ETC1-1-13
3
2
1
3
2
1
ADT1_1WT
0 OHM
R111
CML
4
5
P
T4
S
ETC1-1-13
3
2
1
0 OHM
R132
DNP
R133
0 OHM
R6
DEFAULT AMPLIFIER INPUT PAT H
0 OHM
R55
T11
C51
P
ETC1-1-13
0 OHM
F
0.1U
R134
R135
INB+
24.9 OHM
24.9 OHM
C38
R128
R66
R68
F
R129
C30
4.12K
R69
2
2
0.1U
C82
0.1U
C7
100 OHM
4
3
2
1
VIN
RDN
RGN
RGP
RDP
5
16
VIP
R131
Z2
7
AMP+B
0 OHM
R96
AMP-B
GND
VON
VCC
8
GND
R53
VOP
VCC
13
AMPVDD
AD8352
VCM
14
GND
0 OHM
R95
CML
0 OHM
6
ENB
15
B
R94
A
C60
0.1U
9
10
11
12
R70
R71
10KOHM
W2
C61
0.1U
C24
0.1U
C62
10U
C83
0.1U
AMPVDD
0.001U
C140
0.001U
C46
57.6 OHM
OPTIONAL AMPL IFIER INPUT PATH
F
0 OHM
R72
10K OHM
33 OHM
33 OHM
Rev. B | Page 55 of 76
R73
33 OHM
R74
33 OHM
L19 1
IND0603
L18 1
IND0603
120NH
DNP
120NH
DNP
2
2
C84
4.7PF
L21 1
IND0603
C19
18PF
DNP
L20 1
IND0603
180NH
DNP
180NH
DNP
2
2
R80
R81
VIN+B
VIN-B
0 OHM
0 OHM
TP17
1
TP16
1
AMP-B
C29
12PF
DNP
AMP+B
AVDD
AVDD
06571-076
AMPVDD
AD9627
S6
SMA200U
P
ENC\
ENC
S5
1
1
R30
R7
R8
57.6 OHM
57.6 OHM
SMA200U
P
2
2
0 OHM
10K OHM
10K OHM
R85
R82
0 OHM
R3
0 OHM
R90
Figure 77. Evaluation Board Schematic, DUT Clock Input
0.001U
C77
0.001U
C94
0.001U
C63
0.001U
4
5
0.1U
OPT_CLK-
3
S 2
T5
ETC1-1-13
P
1
6 T9
5
4
ADT1_1WT
1
2
3
C56
0.001U
C79
0 OHM
R33
0 OHM
R32
0.001U
C78
OPT_CLK-
ALTCLK-
OPT_CLK+
ALTCLK+
0 OHM
R79
0 OHM
R101
0 OHM
R99
0 OHM
R78
R83
0.1U
C21
24.9 OHM
R84
0.1U
C20
24.9 OHM
OPT_CLK+
0.1U
1
C64
F
Rev. B | Page 56 of 76
2
C145
TP2
CLK-
CLK+
06571-077
VS
AD9627
DNP
R34
1
S7
RES040 2
0 OHM
R12 5
RES040 2
VS_OUT_DR
C10 1
0.1U
C10 0
0.1U
0 OHM
R12 4
R1 0
0 OHM
VCXO_CLK +
0.1U
C10 4
VCXO_CLK -
1
CLK IN
AD9516
LD
49.9 OHM
TES T
2
0.1U
C9 8
0.1U
C14 3
0.1U
C14 2
18PF
C8 0
0.1U
C99
VS
SCL K
VCP
BYPASS_LD O
9
LF
CLKB
NC1
SCL K
14
15
16
0.1U
0.1U
C97
CLK
13
C96
VS_CLK_DIS T
VS_VC O
11
12
BYPASS_LD O
10
LF
SYNC B
REF_SE L
8
STATU S
6
SYNC B
STATU S
CP
VCP
5
4
LD
3
REFMO N
2
7
CP
VCP
REFMO N
VS_PLL_ 1
1
REF_SE L
TEST
1
TP18
TEST
1
TP19
VS
AGN D
R12
GND_REF 59
OPT_CLKOPT_CLK+
VS
4.12K
VS
VS_OUT_D R
U2
AD9516_64LFCS P
OUT0 56
OUT4
25
TP20
R89
OUT0B 55
OUT4B
26
VS_OUT01_DRV 54
VS_OUT45_DRV
27
R11
REFINB 63
NC2
OUT1 53
OUT5
28
VS
38
37
36
35
34
33
VS_OUT23_DI V
GND_OUT89_DI V
OUT9 B
OUT 9
OUT8 B
OUT 8
VS
39
OUT3 B
VS
AGN D
R92
200
R91
200
40
OUT 3
R88
200
41
VS_OUT23_DR V
R86
200
ALTCLK +
42
OUT2 B
VS_OUT_D R
ALTCLK -
43
LVPECL
TO ADC
44
AGN D
1TP8
SYN C
OUT 2
45
46
47
48
R9
GND_ES D
OUT7 B
OUT 7
OUT6 B
OUT 6
0.001 U
C14 1
OUT6 N
100 OHM
5.1K
18
REFIN 64
CSB
17
CSB_2
CP_RSET 62
NC3
19
VS_PLL_ 261
NC4
20
VS_PRESCALER 60
SDO
21
SDO
SDIO
22
SDI
OUT1B 52
OUT5B
29
RSET_CLOCK 58
RESETB
23
RESETB
VS_OUT67_ 250
VS_OUT45_DI V
30
VS_OUT01_DI V51
VS_OUT89_ 1
VS_REF 57
PDB
24
PDB
Figure 78. Evaluation Board Schematic, Optional AD9516 Clock Circuit
VS_OUT_DR
VS_OUT67_ 149
VS_OUT89_ 2
Rev. B | Page 57 of 76
31
0.1U
C86
0.1U
C85
0.1U
C87
0.1U
C88
1
1
1
1
S8
S9
S10
S11
2
32
2
PAD
2
LVDS
LVPECL
OUTPUT
OUTPUT
06571-078
OUT6 P
AD9627
2
100 OHM
R75
CP
Figure 79. Evaluation Board Schematic, Optional AD9516 Loop Filter/VCO and SYNC Input
BYPASS_LDO
VAL
R136
SYNC
S12
SMA200U P
2
1
R45
R98
VAL
C90
SEL
RES060 3
57.6 OH M
C89
SEL
R93
VAL
VAL
R137
SEL
C91
C144
SEL
LD
Charge Pump Filter
0.1U
C25
VAL
R97
3
2
A2
GND
A1
NL27WZ0
C92
SEL
4
Y1
Y2
VCC
0 OH M
R116
RES040 2
0 OH M
R117
RES040 2
4
5
6
RES040 2
LF
TP1
1
R87
OSCVECTRON_VS500
RES040 2
0 OH M
R104
U25
4
OUT2
3
GND
6
VCC
5
OUT1
24.9 OH M
2
OUT_DISABLE
VS-500
1
FREQ_CTRL_V
33 OH M
R46
SYNC
R106
R108
U3
10K OH M
10K OH M
1
VS
10K OH M
R114
VCP
RES040 2
RES040 2
0 OH M
RES040 2
R139
0 OH M
VCP
RES040 2
VS
R107
R109
R100
10K OH M
C26
0.1U
RES040 2
RES040 2
Rev. B | Page 58 of 76
10K OH M
AC
RES040 2
R76
200
REF_SEL
10K OH M
R102
VCXO_CLK-
VCXO_CLK+
VS
PDB
VS
SYNCB
VS
RESETB
06571-079
VS
AD9627
RES040 2
10K OH M
R105
RES040 2
10K OH M
R103
RES040 2
Rev. B | Page 59 of 76
Figure 80. Evaluation Board Schematic, DUT
NC
D7A
NC
DVDD2
FD3B
FD2B
D11A_MSB_
FD1B
FD0B
FD0A
FD1A
SYNC
FD2A
SPI_CSB
CLK-
FD3A
CLK+
57
52
51
50
49
C137
0.001U
D0B_LSB
U1
SPI_SCLK/DFS
D6A
C121
0.1U
C120
0.1U
RES040 2
SPI_SDIO/DCS
AVDD3
D1B
C109
0.1U
C40
0.1U
48
47
46
AVDD2
VIN+B
DRVDD1
C122
0.001U
C126
0.001U
SPI_SCL K
SPI_SDI O
AVDD
45
44
DRGND1
C127
0.001U
R64
0 OH M
AVDD
VIN+ B
43
VIN-B
RBIAS
AD9627
0.001U
D2B
D1A
D2A
63
62
61
60
59
58
56
55
54
53
R57
22 oh m
9
10
11
12
13
14
15
16
RPAK 8
DRVDD
D4B
D5B
D6B
D7B
D8B
D9B
D10B
D11B_MSB
DCOB
DCOA
NC
NC
D0A_LSB
64
AVD D
1
10K OH M
VIN- B
42
41
CML
C36
0.1U
C35
DRVD D
D3B
DVD D
TP6
RES040 2
0.1U
40
SENSE
VREF
VIN-A
VIN+A
D10A
CML
39
38
37
D9A
R63
RES040 2
C32
VIN- A
VIN+ A
D8A
AVDD
C14
0.1U
TP3
DVDD1
1
TP5
C15
1U
R112
AVDD1
32
36
31
35
30
AVD D
29
SMI_SDFS
28
PWR_SDFS
SMI_SCLK/PDWN
27
34
33
1
25
J6 - INSTALLFOR EXTERNALREFERENCEMODE
RES040 2
0 OH M
26
J5 - INSTALL FOR IV VREF/2V INPUT SPAN
R62
24
SMI_SDO/OEB
0 OH M
R115
23
J4 - INSTALL FOR 0.5V VREF/IV INPUT SPAN
J8 - INSTALLFOR OUTPUTDISABLE
PWR_SCL K
PWR_SD O
FD3A
FD2A
FD1A
FD0A
8
7
6
5
4
3
2
1
9
10
11
12
13
14
15
16
J7 - INSTALLFOR PDWN
RES040 2
RPAK 8
0 OH M
22 oh m
R113
22
D5A
CLK+
21
DRGND
CLK-
DVDD
20
D4A
SPI_CSB
19
D3A
SYN C
18
DVDD
17
8
7
6
5
4
3
2
1
1
2
3
4
5
6
7
8
9
DRVD D
10
11
12
13
14
15
16
5
6
7
8
RPAK 4
22 oh m
SPARE 2
SPARE 1
FD3 B
FD2 B
FD1 B
FD0 B
R58
C34
R59
RPAK 8
22 oh m
R60
RPAK 8
4
3
2
1
0.001U
9
10
11
12
13
14
15
16
9
10
11
12
13
14
15
16
22 oh m
8
7
6
5
4
3
2
1
0.1U
R61
RPAK 8
22 oh m
C33
9
10
11
12
13
14
15
16
8
7
6
5
4
3
2
1
8
7
6
5
4
3
2
1
D3B
D2B
D1B
D0B
1
1
1
1
D11 A
D10 A
D9A
D8A
D7A
D6A
D5A
D4A
D11 B
D10 B
D9B
D8B
D7B
D6B
D5B
D4B
D3A
D2A
D1A
D0A
SPARE 4
SPARE 3
DCO A
DCO B
06571-080
DRVDD
AD9627
D5A
D4A
Figure 81. Evaluation Board Schematic, Digital Output Interface
FD1B
FD0B
V_DIG
SPARE2
SPARE1
FD3B
FD2B
D3B
D2B
V_DIG
D1B
D0B
D5B
D4B
D7B
D6B
D11B
D10B
V_DIG
D9B
D8B
SPARE4
SPARE3
DCOA
DCOB
D3A
D2A
V_DIG
D1A
D0A
D7A
D6A
D11A
D10A
V_DIG
D9A
D8A
FD3A
FD2A
FD1A
FD0A
V_DIG
PWR_SDO
PWR_SDFS
PWR_SCLK
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
U17
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
74VCX162244MTD
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
74VCX162244MTD
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
U16
74VCX162244MTD
V_DIG
V_DIG
V_DIG
V_DIG
SDO_OUT
SDFS_OUT
SCLK_OUT
OUT6P
OUT6N
J11
BG1
BG2
BG3
BG4
BG5
BG6
BG7
BG8
BG9
BG10
DG1
DG2
DG3
DG4
DG5
DG6
DG7
DG8
DG9
DG10
CSB
TYCO_HM-ZD
CHANNELB
B1
C10
D10
C9
D9
A9
B9
C8
D8
A8
B8
C7
D7
A7
B7
C6
D6
A6
B6
A10
B10
C5
D5
A5
B5
C4
D4
A4
B4
C3
D3
A3
B3
C2
D2
A2
B2
C1
D1
A1
CSB_2
SCLK
TYCO_HM-ZD
J10
BG1
BG2
BG3
BG4
BG5
BG6
BG7
BG8
BG9
BG10
DG1
DG2
DG3
DG4
DG5
DG6
DG7
DG8
DG9
DG10
R140
RES040 2
0 OHM
R145
RES040 2
0 OHM
R144
VS
0 OHM
SCLK_OUT
OUT6N
R143
0 OHM
TP22
TEST
1
SDO_OUT
SDFS_OUT
RES040 2
0 OHM
R142
RES040 2
TP23 TEST
1
TP24 TEST
1
OUT6P
SYNC
SDI
RES040 2
0 OHM
R119
R141
RES040 2
SDO
RESET B
TP21
TEST
1
VS
R118
CHANNELA
B1
C10
D10
C9
D9
A9
B9
C8
D8
A8
B8
C7
D7
A7
B7
C6
D6
A6
B6
A10
B10
C5
D5
A5
B5
C4
D4
A4
B4
C3
D3
A3
B3
C2
D2
A2
B2
C1
D1
A1
A1
D1
C1
B2
A2
D2
C2
B3
A3
D3
C3
B4
A4
D4
C4
B5
A5
D5
C5
B10
A10
B6
A6
D6
C6
B7
A7
D7
C7
B8
A8
D8
C8
B9
A9
D9
C9
D10
C10
B1
J12
DG10
DG9
DG8
DG7
DG6
DG5
DG4
DG3
DG2
DG1
BG10
BG9
BG8
BG7
BG6
BG5
BG4
BG3
BG2
BG1
TYCO_HM-ZD
V_DIG
V_DIG
C65
0.1U
C66
0.1U
C72
0.1U
C67
0.1U
C73
0.1U
C68
0.1U
C74
0.1U
C69
0.1U
C75
0.1U
C70
0.1U
C76
0.1U
C71
0.1U
06571-081
DIGITAL/HSC-ADC-EVALCZ INTERFACE
10K OHM
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
RES040 2
U15
R130
VAL
R77
Rev. B | Page 60 of 76
100 OHM
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
AD9627
RES040 2
10K OHM
Figure 82. Evaluation Board Schematic, SPI Circuitry
Rev. B | Page 61 of 76
SDO
SDI
CSB
SCLK
CSB_2
R65
CSB
SCLK
V_DIG
RES0402
10K OHM
C13
0.1U
3
2
1
A2
A2
Y2
VCC
Y1
4
5
6
Y1
4
5
6
V_DIG
V_DIG
C81
0.1U
Y2
VCC
NC7WZ07P6X
GND
RES0603
U7 1K OHM
A1
U8
3
2
1
NC7WZ16P6X
GND
A1
10K OHM
R24
RES0402
10K OHM
R18
RES0402
R19
R17
RES0603
1K OHM
R21
RES0603
100K OHM
V_DIG
SDO
V_DIG
RES0603
1K OHM
R20
SPI_CSB
VS
J2 - JUMPER PINS 2 TO 3 FOR SPI OPERATION
JUMPER PINS 1 TO 2 FOR TWOS COMPLEMENT OUTPUT
J1 - JUMPER PINS 2 TO 3 FOR SPI OPERATION
JUMPER PINS 1 TO 2 FOR DCS ENABLE
3
RES0603
100K OHM
R23
RES0603
100K OHM
R22
J2
3
1
J1
SPI_SCLK
SPI_SDIO
1
V_DIG
J21 - INSTALL JUMPER FOR SPI OPERATION
V_DIG
06571-082
SDI
AD9627
1
3
SMDC110F
C41
10U
Figure 83. Evaluation Board Schematic, Power Supply
Rev. B | Page 62 of 76
P4
P3
P2
P1
VCP
VS
DRVDDIN
SJ35
P4
6
P6
5
P5
4
P4
P33
2
P2
P3
P11
1
1
AVDDIN
CR7
OPTIONAL POWER SUPPLY INPUT S
POWER_JACK
F2
2
1
2
L6
IND1210
10UH
10uh
L10
IND1210
L9
IND1210
10UH
1
2
2
2
BNX- 016
3 PSG
1 BIAS
C53
10U
C102
10U
C52
10U
C58
0.1U
C103
0.1U
C57
0.1U
CG6
CG5
CG 4
CB 2
1
1
2
PWR_IN
L11
IND1210
10uh
2
DRVDD
DVDD
AVDD
RES0603
CR8
R16
1
C54
10U
CR10
S2A_REC
T
TP25
1
SHOT_RECT
261 OHM
2
C59
0.1U
CR11
2
1
V_DIG
1TP4
1
1
TP13
1
TP12
1
TP10
1
1TP9
C42
1U
SD
6
8 IN
7 IN2
ADP3334
2
C44
1U
CR12
S2A_REC
T
GND TEST POINT S
1
S2A_REC
T
3
VR3
PAD
5
GND
OUT
VR1
OUT 1
OUT2 2
FB 3
IN
4
GND
1
F1
C43
1U
1
1.8
2.5
3.3
DR VDD
R1 3
76.8 K
107 K
140 K
2
147 K
94.0 K
78.7 K
R1 4
C93
0.001U
L3
IND1210
10uh
DRVDD SETTIN G
ADP3339
R13
R14
J16
140 KOHM
S2A_REC
T
78.7 KOHM
AC
C45
1U
AVDDIN
1
L4
IND1210
10uh
2
DRVDDIN
06571-083
POWER INPU T
6V, 2A MA X
AD9627
PWR_IN
PWR_IN
Figure 84. Evaluation Board Schematic, Power Supply (Continued)
Rev. B | Page 63 of 76
VC P
SD
6
PA D
ADP333 9
VC P
5
C12 4
10 U
10 U
VS_OUT_DR
C11 9
GN D
OUT 1
OUT2 2
FB 3
VR2
OU T
OU T
Power Supply ByPass Capacitors
1U
C13 2
8 IN
7 IN2
ADP3334
1U
IN
VR 6
C13 5
3
1U
C13 3
PA D
ADP333 9
4
GN D
1
4
GN D
1
IN
VS
1U
C13 6
1U
C13 4
10 U
C11 8
R2 5
R1 5
VR 5
140 KOH M
0.001 U
C9 5
SJ36
78.7 KOH M
1
1
1
2
2
1U
C13 1
L1 3
IND121 0
10uh
L1 2
IND121 0
10uh
L8
IND121 0
10UH
2
VS
VC P
VS
VS_OUT_D R
C11 2
0.1 U
C11 0
0.1 U
PWR_IN
0.1 U
C10 8
1U
C12 9
3
IN
PA D
ADP333 9
0.1 U
C11 1
VR 4
4
GN D
1
3
0.1 U
C11 5
OU T
0.1 U
C11 4
0.1 U
C11 3
1U
C13 0
1
2
0.1 U
C10 7
L1
IND121 0
10UH
0.1 U
C11 6
0.1 U
C10 5
AMPVD D
06571-084
PWR_IN
AD9627
SJ37
AD9627
06571-085
EVALUATION BOARD LAYOUTS
Figure 85. Evaluation Board Layout, Primary Side
Rev. B | Page 64 of 76
06571-086
AD9627
Figure 86. Evaluation Board Layout, Ground Plane
Rev. B | Page 65 of 76
06571-087
AD9627
Figure 87. Evaluation Board Layout, Power Plane
Rev. B | Page 66 of 76
06571-088
AD9627
Figure 88. Evaluation Board Layout, Power Plane
Rev. B | Page 67 of 76
06571-089
AD9627
Figure 89. Evaluation Board Layout, Ground Plane
Rev. B | Page 68 of 76
06571-090
AD9627
Figure 90. Evaluation Board Layout, Secondary Side (Mirrored Image)
Rev. B | Page 69 of 76
06571-091
AD9627
Figure 91. Evaluation Board Layout, Silkscreen, Primary Side
Rev. B | Page 70 of 76
06571-092
AD9627
Figure 92. Evaluation Board Layout, Silkscreen, Secondary Side
Rev. B | Page 71 of 76
AD9627
BILL OF MATERIALS
Table 26. Evaluation Board Bill of Materials (BOM)1, 2
Item
1
2
Qty
1
55
3
1
Reference
Designator
AD9627CE_REVB
C1 to C3, C6, C7,
C13, C14, C17, C18,
C20 to C26, C32,
C57 to C61, C65
to C76, C81 to
C83, C96 to C101,
C103, C105, C107,
C108, C110 to
C116, C145
C80
4
2
C5, C84
5
10
6
13
7
10
8
1
C33, C35, C63,
C93 to C95, C122,
C126, C127, C137
C15, C42 to C45,
C129 to C136
C27, C41, C52 to
C54, C62, C102,
C118, C119, C124
CR5
9
2
CR6, CR9
Description
PCB
0.1 μF, 16 V ceramic
capacitor, SMT 0402
Package
PCB
C0402SM
Manufacturer
Analog Devices
Murata
Mfg. Part Number
GRM155R71C104KA88D
18 pF, COG, 50 V, 5% ceramic
capacitor, SMT 0402
4.7 pF, COG, 50 V, 5% ceramic
capacitor, SMT 0402
0.001 μF, X7R, 25 V, 10%
ceramic capacitor, SMT 0402
C0402SM
Murata
GJM1555C1H180JB01J
C0402SM
Murata
GJM1555C1H4R7CB01J
C0402SM
Murata
GRM155R71H102KA01D
1 μF, X5R, 25 V, 10% ceramic
capacitor, SMT 0805
10 μF, X5R, 10 V, 10% ceramic
capacitor, SMT 1206
C0805
Murata
GR4M219R61A105KC01D
C1206
Murata
GRM31CR61C106KC31L
Schottky diode HSMS2822, SOT23
SOT23
Avago Technologies
HSMS-2822-BLKG
LED RED, SMT, 0603, SS-type
LED0603
Panasonic
LNJ208R8ARA
10
4
CR7, CR10 to CR12
50 V, 2 A diode
DO_214AA
Micro Commercial Components
S2A-TP
11
1
CR8
30 V, 3 A diode
DO_214AB
Micro Commercial Components
SK33-TP
12
1
F1
EMI filter
FLTHMURATABNX01
Murata
BNX016-01
13
1
F2
L1206
Tyco Raychem
NANOSMDC150F-2
14
2
J1 to J2
HDR3
Samtec
TWS-1003-08-G-S
15
9
HDR2
Samtec
TWS-102-08-G-S
16
3
J4 to J9, J18, J19,
J21
J10 to J12
6.0 V, 3.0 A, trip current
resettable fuse
3-pin, male, single row,
straight header
2-pin, male, straight header
Interface connector
TYCO_HM_ZD
Tyco
6469169-1
17
1
J14
8-pin, male, double row,
straight header
DC power jack connector
CNBERG2X4H350LD
Samtec
TSW-104-08-T-D
PWR_JACK1
Cui Stack
PJ-002A
10 μH, 2 A bead core, 1210
1210
Panasonic
EXC-CL3225U1
6-terminal connector
PTMICRO6
Weiland Electric, Inc.
Z5.531.3625.0
18
1
J16
19
10
20
1
L1, L3, L4, L6, L8
to L13
P3
21
1
P4
4-terminal connector
PTMICRO4
Weiland Electric, Inc.
Z5.531.3425.0
22
3
R7, R30, R45
R0603
NIC Components
NRC06F57R6TRF
23
27
R0402SM
NIC Components
NRC04ZOTRF
24
2
R2, R3, R4, R32,
R33, R42, R64, R67,
R69, R90, R96, R99,
R101, R104, R110
to R113, R115,
R119, R121, R123,
R141 to R145
R13, R25
57.6 Ω, 0603, 1/10 W,
1% resistor
0 Ω, 1/16 W, 5% resistor
R0603
NIC Components
NRC06F1403TRF
25
2
R14, R15
R0603
NIC Components
NRC06F7872TRF
140 kΩ, 0603, 1/10 W,
1% resistor
78.7 kΩ, 0603, 1/10 W,
1% resistor
Rev. B | Page 72 of 76
AD9627
Item
26
Qty
1
Reference
Designator
R16
27
3
R17, R22, R23
28
7
29
3
R18, R24, R63, R65,
R82, R118, R140
R19, R20, R21
30
9
31
5
R26, R27, R43,
R46, R47, R70,
R71, R73, R74
R57, R59 to R62
32
1
R58
33
1
R76
34
4
S2, S3, S5 ,S12
Description
261 Ω, 0603, 1/10 W,
1% resistor
100 kΩ, 0603, 1/10 W,
1% resistor
10 kΩ, 0402, 1/16 W, 1%
resistor
1 kΩ, 0603, 1/10 W, 1%
resistor
33 Ω, 0402, 1/16 W, 5%
resistor
Package
R0603
Manufacturer
NIC Components
Mfg. Part Number
NRC06F2610TRF
R0603
NIC Components
NRC06F1003TRF
R0402SM
NIC Components
NRC04F1002TRF
R0603
NIC Components
NRC06F1001TRF
R0402SM
NIC Components
NRC04J330TRF
22 Ω, 16-pin, 8-resistor,
resistor array
R_742
CTS Corporation
742C163220JPTR
RES_ARRY
CTS Corporation
742C083220JPTR
R0402SM
NIC Components
NCR04F2000TRF
SMA_EDGE
142-0701-201
35
1
SJ35
22 Ω, 8-pin, 4-resistor,
resistor array
200 Ω, 0402, 1/16 W,
1% resistor
SMA, inline, male,
coaxial connector
0 Ω, 1/8 W, 1% resistor
SLDR_PAD2MUYLAR
Emerson Network
Power
NIC Components
36
5
T1 to T5
Balun
TRAN6B
M/A-COM
MABA-007159-000000
37
1
U1
IC, AD9627
LFCSP64-9X9-9E
Analog Devices
AD9627BCPZ
38
1
U2
Clock distribution, PLL IC
LFCSP64-9X9
Analog Devices
AD9516-4BCPZ
39
1
U3
Dual inverter IC
SC70_6
Fairchild Semiconductor
NC7WZ04P6X_NL
40
1
U7
SC70_6
Fairchild Semiconductor
NC7WZ07P6X_NL
41
1
U8
Dual buffer IC,
open-drain circuits
UHS dual buffer IC
SC70_6
Fairchild Semiconductor
NC7WZ16P6X_NL
74VCX16244MTDX_NL
NRC10ZOTRF
42
3
U15 to U17
16-bit CMOS buffer IC
TSOP48_8_1MM
Fairchild Semiconductor
43
2
VR1, VR2
Adjustable regulator
LFCSP8-3X3
Analog Devices
ADP3334ACPZ
44
1
VR3
1.8 V high accuracy regulator
SOT223-HS
Analog Devices
ADP3339AKCZ-1.8
45
1
VR4
5.0 V high accuracy regulator
SOT223-HS
Analog Devices
ADP3339AKCZ-5.0
46
2
VR5, VR6
3.3 V high accuracy regulator
SOT223-HS
Analog Devices
ADP3339AKCZ-3.3
47
1
Y1
Oscillator clock, VFAC3
OSC-CTS-CB3
Valpey Fisher
VFAC3-BHL
48
2
Z1, Z2
High speed IC, op amp
LFCSP16-3X3-PAD
Analog Devices
AD8352ACPZ
1
2
This bill of materials is RoHS compliant.
The bill of materials lists only those items that are normally installed in the default condition. Items that are not installed are not included in the BOM.
Rev. B | Page 73 of 76
AD9627
OUTLINE DIMENSIONS
0.60 MAX
9.00
BSC SQ
0.60
MAX
64 1
49
PIN 1
INDICATOR
48
PIN 1
INDICATOR
8.75
BSC SQ
0.50
BSC
0.50
0.40
0.30
0.22 MIN
7.50
REF
0.05 MAX
0.02 NOM
SEATING
PLANE
0.30
0.23
0.18
0.20 REF
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
COMPLIANT TO JEDEC STANDARDS MO-220-VMMD-4
02-23-2010-B
0.80 MAX
0.65 TYP
12° MAX
16
17
33
32
TOP VIEW
1.00
0.85
0.80
7.55
7.50 SQ
7.45
EXPOSED PAD
(BOTTOM VIEW)
Figure 93. 64-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
9 mm × 9 mm Body, Very Thin Quad
(CP-64-6)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
AD9627ABCPZ-150
AD9627ABCPZ-125
AD9627ABCPZ-105
AD9627ABCPZ-80
AD9627-150EBZ
AD9627-125EBZ
1
Temperature Range
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
Package Description
64-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
64-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
64-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
64-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
Evaluation Board
Evaluation Board
Z = RoHS Compliant Part.
Rev. B | Page 74 of 76
Package Option
CP-64-6
CP-64-6
CP-64-6
CP-64-6
AD9627
NOTES
Rev. B | Page 75 of 76
AD9627
NOTES
©2007–2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D06571-0-5/10(B)
Rev. B | Page 76 of 76
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