Datasheet AD9201 Datasheet (Analog Devices)

Dual Channel, 20 MHz 10-Bit
a
FEATURES Complete Dual Matching ADCs Low Power Dissipation: 215 mW (+3 V Supply) Single Supply: 2.7 V to 5.5 V Differential Nonlinearity Error: 0.4 LSB On-Chip Analog Input Buffers On-Chip Reference Signal-to-Noise Ratio: 57.8 dB Over Nine Effective Bits Spurious-Free Dynamic Range: –73 dB No Missing Codes Guaranteed 28-Lead SSOP
PRODUCT DESCRIPTION
The AD9201 is a complete dual channel, 20 MSPS, 10-bit CMOS ADC. The AD9201 is optimized specifically for applica­tions where close matching between two ADCs is required (e.g., I/Q channels in communications applications). The 20 MHz sampling rate and wide input bandwidth will cover both narrow­band and spread-spectrum channels. The AD9201 integrates two 10-bit, 20 MSPS ADCs, two input buffer amplifiers, an internal voltage reference and multiplexed digital output buffers.
Each ADC incorporates a simultaneous sampling sample-and­hold amplifier at its input. The analog inputs are buffered; no external input buffer op amp will be required in most applica­tions. The ADCs are implemented using a multistage pipeline architecture that offers accurate performance and guarantees no missing codes. The outputs of the ADCs are ported to a multi­plexed digital output buffer.
The AD9201 is manufactured on an advanced low cost CMOS process, operates from a single supply from 2.7 V to 5.5 V, and consumes 215 mW of power (on 3 V supply). The AD9201 input structure accepts either single-ended or differential signals, providing excellent dynamic performance up to and beyond its 10 MHz Nyquist input frequencies.
Resolution CMOS ADC
AD9201
FUNCTIONAL BLOCK DIAGRAM
IINA IINB
IREFB IREFT
QREFB QREFT
VREF
REFSENSE
QINB QINA
AVDD AVSS
"I" ADC
REFERENCE
BUFFER
"Q" ADC
CLOCK
I
REGISTER
ASYNCHRONOUS
MULTIPLEXER
1V
Q
REGISTER
PRODUCT HIGHLIGHTS
1. Dual 10-Bit, 20 MSPS ADCs A pair of high performance 20 MSPS ADCs that are opti­mized for spurious free dynamic performance are provided for encoding of I and Q or diversity channel information.
2. Low Power Complete CMOS Dual ADC function consumes a low 215 mW on a single supply (on 3 V supply). The AD9201 operates on supply voltages from 2.7 V to 5.5 V.
3. On-Chip Voltage Reference The AD9201 includes an on-chip compensated bandgap voltage reference pin programmable for 1 V or 2 V.
4. On-chip analog input buffers eliminate the need for external op amps in most applications.
5. Single 10-Bit Digital Output Bus The AD9201 ADC outputs are interleaved onto a single output bus saving board space and digital pin count.
6. Small Package The AD9201 offers the complete integrated function in a compact 28-lead SSOP package.
7. Product Family The AD9201 dual ADC is pin compatible with a dual 8-bit ADC (AD9281) and has a companion dual DAC product, the AD9761 dual DAC.
DVDD DVSS
AD9201
THREE-
STATE OUTPUT BUFFER
SLEEP SELECT
DATA 10 BITS
CHIP SELECT
REV. D
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781/329-4700 World Wide Web Site: http://www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 1999
AD9201–SPECIFICATIONS
(AVDD = +3 V, DVDD = +3 V, F internal ref, differential input signal, unless otherwise noted)
= 20 MSPS, VREF = 2 V, INB = 0.5 V, T
SAMPLE
MIN
to T
Parameter Symbol Min Typ Max Units Condition
RESOLUTION 10 Bits
CONVERSION RATE F
S
20 MHz
DC ACCURACY
Differential Nonlinearity DNL ±0.4 LSB REFT = 1 V, REFB = 0 V
Integral Nonlinearity INL 1.2 LSB
Differential Nonlinearity (SE) DNL ±0.5 ±1 LSB REFT = 1 V, REFB = 0 V Integral Nonlinearity (SE) INL ±1.5 ±2.5 LSB
Zero-Scale Error, Offset Error E Full-Scale Error, Gain Error E
ZS
FS
±1.5 ±3.8 % FS ±3.5 ±5.4 % FS
Gain Match ±0.5 LSB Offset Match ±5 LSB
ANALOG INPUT
Input Voltage Range AIN –0.5 AVDD/2 V Input Capacitance C Aperture Delay t Aperture Uncertainty (Jitter) t
IN
AP
AJ
2pF 4ns
2ps Aperture Delay Match 2 ps Input Bandwidth (–3 dB) BW
Small Signal (–20 dB) 240 MHz Full Power (0 dB) 245 MHz
INTERNAL REFERENCE
Output Voltage (1 V Mode) VREF 1 V REFSENSE = VREF
Output Voltage Tolerance (1 V Mode) ±10 mV
Output Voltage (2 V Mode) VREF 2 V REFSENSE = GND
Output Voltage Tolerance (2 V Mode) ±15 mV Load Regulation (1 V Mode) ±28 mV 1 mA Load Current Load Regulation (2 V Mode) ±15 mV 1 mA Load Current
POWER SUPPLY
Operating Voltage AVDD 2.7 3 5.5 V AVDD – DVDD ≤ 2.3 V
DRVDD 2.7 3 5.5 V
Supply Current I
Power Consumption P
AVDD
I
DRVDD
D
71.6 mA AVDD = 3 V
0.1 mA
215 245 mW AVDD = DVDD = 3 V Power-Down 15.5 mW STBY = AVDD, Clock = AVSS Power Supply Rejection PSR 0.8 1.3 % FS
DYNAMIC PERFORMANCE
1
Signal-to-Noise and Distortion SINAD
f = 3.58 MHz 55.6 57.3 dB f = 10 MHz 55.8 dB
Signal-to-Noise SNR
f = 3.58 MHz 55.9 57.8 dB f = 10 MHz 56.2 dB
Total Harmonic Distortion THD
f = 3.58 MHz –69 –63.3 dB f = 10 MHz –66.3 dB
Spurious Free Dynamic Range SFDR
f = 3.58 MHz –66 –73 dB f = 10 MHz –70.5 dB
Two-Tone Intermodulation Distortion
2
IMD –62 dB f = 44.49 MHz and 45.52 MHz Differential Phase DP 0.1 Degree NTSC 40 IRE Mod Ramp Differential Gain DG 0.05 % F
= 14.3 MHz
S
Crosstalk Rejection 68 dB
MAX,
–2–
REV. D
Parameter Symbol Min Typ Max Units Condition
DYNAMIC PERFORMANCE (SE)
3
Signal-to-Noise and Distortion SINAD
f = 3.58 MHz 52.3 dB
Signal-to-Noise SNR
f = 3.58 MHz 55.5 dB
Total Harmonic Distortion THD
f = 3.58 MHz –55 dB
Spurious Free Dynamic Range SFDR
f = 3.58 MHz –58 dB
DIGITAL INPUTS
High Input Voltage V Low Input Voltage V DC Leakage Current I Input Capacitance C
IH
IL
IN
IN
2.4 V
0.3 V
±6 µA
2pF
LOGIC OUTPUT (with DVDD = 3 V)
High Level Output Voltage
(I
= 50 µA) V
OH
OH
2.88 V
Low Level Output Voltage
(IOL = 1.5 mA) V
OL
0.095 V
LOGIC OUTPUT (with DVDD = 5 V)
High Level Output Voltage
(I
= 50 µA) V
OH
OH
4.5 V
Low Level Output Voltage
= 1.5 mA) V
(I
OL
Data Valid Delay t MUX Select Delay t Data Enable Delay t
OL
OD
MD
ED
0.4 V 11 ns 7ns 13 ns CL = 20 pF. Output Level to
90% of Final Value
Data High-Z Delay t
DHZ
13 ns
CLOCKING
Clock Pulsewidth High t Clock Pulsewidth Low t
CH
CL
22.5 ns
22.5 ns
Pipeline Latency 3.0 Cycles
NOTES
1
AIN differential 2 V p-p, REFT = 1.5 V, REFB = –0.5 V.
2
IMD referred to larger of two input signals.
3
SE is single ended input, REFT = 1.5 V, REFB = –0.5 V.
Specifications subject to change without notice.
AD9201
REV. D
CLOCK
INPUT
SELECT
INPUT
DATA
OUTPUT
t
OD
ADC SAMPLE#1ADC SAMPLE
OUTPUT ENABLED
SAMPLE #1-3
Q CHANNEL
OUTPUT
#2
Q CHANNEL
ADC SAMPLE #3
t
MD
SAMPLE #1-1
Q CHANNEL
OUTPUT
SAMPLE #1-2
Q CHANNEL
OUTPUT
Figure 1. ADC Timing
–3–
ADC SAMPLE #4
SAMPLE #1-1 I CHANNEL OUTPUT
SAMPLE #1 Q CHANNEL OUTPUT
SAMPLE #1
I CHANNEL
OUTPUT
ADC SAMPLE #5
I CHANNEL OUTPUT ENABLED
SAMPLE #2 Q CHANNEL OUTPUT
AD9201
WARNING!
ESD SENSITIVE DEVICE
ABSOLUTE MAXIMUM RATINGS*
With Respect
Parameter to Min Max Units
AVDD AVSS –0.3 +6.5 V DVDD DVSS –0.3 +6.5 V AVSS DVSS –0.3 +0.3 V AVDD DVDD –6.5 +6.5 V CLK AVSS –0.3 AVDD + 0.3 V Digital Outputs DVSS –0.3 DVDD + 0.3 V AINA, AINB AVSS –1.0 AVDD + 0.3 V VREF AVSS –0.3 AVDD + 0.3 V REFSENSE AVSS –0.3 AVDD + 0.3 V REFT, REFB AVSS –0.3 AVDD + 0.3 V
Junction Temperature +150 °C Storage Temperature –65 +150 °C
Lead Temperature
10 sec +300 °C
*Stresses above those listed under Absolute Maximum Ratings may cause perma-
nent 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 sections of this specification is not implied. Exposure to absolute maximum ratings for extended periods may effect device reliability.
ORDERING GUIDE
Temperature Package Package
Model Range Description Options*
AD9201ARS –40°C to +85°C 28-Lead SSOP RS-28
AD9201-EVAL Evaluation Board
*RS = Shrink Small Outline.
PIN CONFIGURATION
DVSS
DVDD
(LSB) D0
(MSB) D9
SELECT
CLOCK
D1 D2 D3 D4 D5 D6 D7 D8
AD9201
TOP VIEW
(Not to Scale)
CHIP-SELECT INA-Q INB-Q REFT-Q REFB-Q AVDD VREF REFSENSE AVSS REFB-I REFT-I INB-I INA-I SLEEP
PIN FUNCTION DESCRIPTIONS
P
in
No. Name Description
1 DVSS Digital Ground 2 DVDD Digital Supply 3 D0 Bit 0 (LSB) 4 D1 Bit 1 5 D2 Bit 2 6 D3 Bit 3 7 D4 Bit 4 8 D5 Bit 5 9 D6 Bit 6 10 D7 Bit 7 11 D8 Bit 8 12 D9 Bit 9 (MSB)
13 SELECT Hi I Channel Out, Lo Q Channel Out 14 CLOCK Clock 15 SLEEP Hi Power Down, Lo Normal Operation
16 INA-I I Channel, A Input 17 INB-I I Channel, B Input 18 REFT-I Top Reference Decoupling, I Channel 19 REFB-I Bottom Reference Decoupling, I Channel 20 AVSS Analog Ground 21 REFSENSE Reference Select 22 VREF Internal Reference Output 23 AVDD Analog Supply 24 REFB-Q Bottom Reference Decoupling, Q Channel 25 REFT-Q Top Reference Decoupling, Q Channel 26 INB-Q Q Channel, B Input 27 INA-Q Q Channel, A Input 28 CHIP-SELECT Hi-High Impedance, Lo-Normal Operation
DEFINITIONS OF SPECIFICATIONS
INTEGRAL NONLINEARITY (INL)
Integral nonlinearity refers to the deviation of each individual code from a line drawn from “zero” through “full scale.” The point used as “zero” occurs 1/2 LSB before the first code tran­sition. “Full scale” is defined as a level 1 1/2 LSBs beyond the last code transition. The deviation is measured from the center of each particular code to the true straight line.
DIFFERENTIAL NONLINEARITY (DNL, NO MISSING CODES)
An ideal ADC exhibits code transitions that are exactly 1 LSB apart. DNL is the deviation from this ideal value. It is often specified in terms of the resolution for which no missing codes (NMC) are guaranteed.
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD9201 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
–4–
REV. D
AVDD
DRVDD
AVDD
AVDD
AVDD
AD9201
AVDD
AVSS
DRVSS
DRVSS
AVSS
a. D0–D9, OTR b. Three-State, Standby c. CLK
AVDD
AVDD
AVSS
AVSS
IN
AVSS
AVDD
AVDD
REFBS
AVSS
REFBF
d. INA, INB e. Reference f. REFSENSE g. VREF
Figure 2. Equivalent Circuits
OFFSET ERROR
The first transition should occur at a level 1 LSB above “zero.” Offset is defined as the deviation of the actual first code transi­tion from that point.
OFFSET MATCH
The change in offset error between I and Q channels.
EFFECTIVE NUMBER OF BITS (ENOB)
For a sine wave, SINAD can be expressed in terms of the num­ber of bits. Using the following formula,
N = (SINAD – 1.76)/6.02
It is possible to get a measure of performance expressed as N, the effective number of bits.
Thus, effective number of bits for a device for sine wave inputs at a given input frequency can be calculated directly from its measured SINAD.
TOTAL HARMONIC DISTORTION (THD)
THD is the ratio of the rms sum of the first six harmonic com­ponents to the rms value of the measured input signal and is expressed as a percentage or in decibels.
SIGNAL-TO-NOISE RATIO (SNR)
SNR is the ratio of the rms value of the measured input signal to the rms sum of all other spectral components below the Nyquist frequency, excluding the first six harmonics and dc. The value for SNR is expressed in decibels.
AVSS
AVDD
AVSS
AVSS
AVDD
AVSS
AVSS
scale. Gain error is the deviation of the actual difference be­tween first and last code transitions and the ideal difference between the first and last code transitions.
GAIN MATCH
The change in gain error between I and Q channels.
PIPELINE DELAY (LATENCY)
The number of clock cycles between conversion initiation and the associated output data being made available. New output data is provided every rising clock edge.
MUX SELECT DELAY
The delay between the change in SELECT pin data level and valid data on output pins.
POWER SUPPLY REJECTION
The specification shows the maximum change in full scale from the value with the supply at the minimum limit to the value with the supply at its maximum limit.
APERTURE JITTER
Aperture jitter is the variation in aperture delay for successive samples and is manifested as noise on the input to the A/D.
APERTURE DELAY
Aperture delay is a measure of the Sample-and-Hold Amplifier (SHA) performance and is measured from the rising edge of the clock input to when the input signal is held for conversion.
SPURIOUS FREE DYNAMIC RANGE (SFDR)
The difference in dB between the rms amplitude of the input signal and the peak spurious signal.
GAIN ERROR
The first code transition should occur for an analog value 1 LSB above nominal negative full scale. The last transition should occur for an analog value 1 LSB below the nominal positive full
REV. D
–5–
SIGNAL-TO-NOISE AND DISTORTION (S/N+D, SINAD) RATIO
S/N+D is the ratio of the rms value of the measured input signal to the rms sum of all other spectral components below the Nyquist frequency, including harmonics but excluding dc. The value for S/N+D is expressed in decibels.
AD9201
INPUT FREQUENCY – Hz
65
60
35
1.00E+05
SNR – dB
50
45
40
55
1.00E+06 1.00E+07 1.00E+08
–6dB
–20dB
–0.5dB
–Typical Characteristic Curves
(AVDD = +3 V, DVDD = +3 V, FS = 20 MHz (50% duty cycle), 2 V input span from –0.5 V to +1.5 V, 2 V internal reference unless otherwise noted)
1.5
1.0
0.5
0
INL
–0.5
–1.0
–1.5
0 768128
Figure 3. Typical INL (1 V Internal Reference)
256 384 512 640
CODE OFFSET
896 1024
Figure 6. SNR vs. Input Frequency
1
0.5
0
DNL
–0.5
–1.0
0
256 384 512 640
128
CODE OFFSET
768
896 1024
Figure 4. Typical DNL (1 V Internal Reference)
1.00
0.80
0.60
0.40
0.20
0.00
– nA
B
I
–0.20
–0.40
–0.60
–0.80 –1.00
–1.0 2.0–0.5
0 0.5 1.0 1.5
INPUT VOLTAGE – V
Figure 5. Input Bias Current vs. Input Voltage
65
60
55
50
SINAD – dB
45
40
35
1.00E+05
–0.5dB
–6dB
–20dB
1.00E+06 1.00E+07 1.00E+08 INPUT FREQUENCY – Hz
Figure 7. SINAD vs. Input Frequency
–30
–35
–40
–45
–50 –55
THD – dB
–60
–65
–70
–75 –80
1.00E+05
–20dB
–6dB
–0.5dB
1.00E+06 1.00E+07 1.00E+08
INPUT FREQUENCY – Hz
Figure 8. THD vs. Input Frequency
–6–
REV. D
–75
CODE
HITS
N–1
1.00E+07
1.20E+07
8.00E+06
6.00E+06
4.00E+06
2.00E+06
0.00E+00 N N+1
10000000
255100
150400
INPUT FREQUENCY – Hz
–12
–15
–30
AMPLITUDE – dB
–21
–24
–27
–18
1.00E+06 1.00E+07 1.00E+08
1.00E+09
–9
–6
–3
0
INPUT FREQUENCY – Hz
60
55
35
1.00E+05 1.00E+08
1.00E+06
SNR – dB
1.00E+07
50
45
40
–0.5dB
–6.0dB
–20.0dB
–70
–65
THD – dB
–60
–55
–50
1.00E+06 1.00E+07 1.00E+08 CLOCK FREQUENCY – Hz
AD9201
Figure 9. THD vs. Clock Frequency (fIN = 1 MHz)
1.012
1.011
1.010
– V
1.009
REF
V
1.008
1.007
1.006 –40 80–20
0204060
TEMPERATURE – 8C
100
Figure 10. Voltage Reference Error vs. Temperature
220
215
210
Figure 12. Grounded Input Histogram
Figure 13. Full Power Bandwidth
205
200
195
190
POWER CONSUMPTION – mW
REV. D
185
180
0
Figure 11. Power Consumption vs. Clock Frequency
4
26 1810 14
8
CLOCK FREQUENCY – MHz
12
16
20
Figure 14. SNR vs. Input Frequency (Single Ended)
–7–
AD9201
ADC
CORE
+FS
LIMIT
–FS
LIMIT
BUFFER
BUFFER
IINA
IINB
V
REF
+FS LIMIT =
V
REF
+V
REF/2
–FS LIMIT = V
REF
–V
REF/2
OUTPUT
WORD
SHA
10
FUND
0 –10 –20 –30 –40 –50 –60
I CHANNEL
–70 –80 –90
–100 –110
–120
0.0E+0
1.0E+6 2.0E+6 3.0E+6 4.0E+6 5.0E+6 6.0E+6 7.0E+6 8.0E+6 9.0E+6 10.0E+6
10
FUND
0 –10 –20 –30 –40 –50 –60
Q CHANNEL
–70 –80 –90
–100 –110
–120
0.0E+0 1.0E+6 2.0E+6 3.0E+6 4.0E+6 5.0E+6 6.0E+6 7.0E+6 8.0E+6 9.0E+6 10.0E+6
2ND
2ND
3RD
4TH
3RD
5TH
4TH
6TH
7TH
5TH
8TH9TH
8TH 9TH
6TH
7TH
Figure 15. Simultaneous Operation of I and Q Channels (Differential Input)
The AD9201 also includes an on-chip bandgap reference and reference buffer. The reference buffer shifts the ground-referred reference to levels more suitable for use by the internal circuits of the converter. Both converters share the same reference and reference buffer. This scheme provides for the best possible gain match between the converters while simultaneously minimizing the channel-to-channel crosstalk. (See Figure 16.)
Each A/D converter has its own output latch, which updates on the rising edge of the input clock. A logic multiplexer, con­trolled through the SELECT pin, determines which channel is passed to the digital output pins. The output drivers have their own supply (DVDD), allowing the part to be interfaced to a variety of logic families. The outputs can be placed in a high impedance state using the CHIP SELECT pin.
The AD9201 has great flexibility in its supply voltage. The analog and digital supplies may be operated from 2.7 V to 5.5 V, independently of one another.
ANALOG INPUT
Figure 16 shows an equivalent circuit structure for the analog input of one of the A/D converters. PMOS source-followers buffer the analog input pins from the charge kickback problems normally associated with switched capacitor ADC input struc­tures. This produces a very high input impedance on the part, allowing it to be effectively driven from high impedance sources. This means that the AD9201 could even be driven directly by a passive antialias filter.
THEORY OF OPERATION
The AD9201 integrates two A/D converters, two analog input buffers, an internal reference and reference buffer, and an out­put multiplexer. For clarity, this data sheet refers to the two converters as “I” and “Q.” The two A/D converters simulta­neously sample their respective inputs on the rising edge of the input clock. The two converters distribute the conversion opera­tion over several smaller A/D subblocks, refining the conversion with progressively higher accuracy as it passes the result from stage to stage. As a consequence of the distributed conversion, each converter requires a small fraction of the 1023 comparators used in a traditional flash-type 10-bit ADC. A sample-and-hold function within each of the stages permits the first stage to oper­ate on a new input sample while the following stages continue to process previous samples. This results in a “pipeline processing” latency of three clock periods between when an input sample is taken and when the corresponding ADC output is updated into the output registers.
The AD9201 integrates input buffer amplifiers to drive the analog inputs of the converters. In most applications, these input amplifiers eliminate the need for external op amps for the input signals. The input structure is fully differential, but the SHA common-mode response has been designed to allow the converter to readily accommodate either single-ended or differ­ential input signals. This differential structure makes the part capable of accommodating a wide range of input signals.
–8–
Figure 16. Equivalent Circuit for AD9201 Analog Inputs
The source followers inside the buffers also provide a level-shift function of approximately 1 V, allowing the AD9201 to accept inputs at or below ground. One consequence of this structure is that distortion will result if the analog input approaches the positive supply. For optimum high frequency distortion perfor­mance, the analog input signal should be centered according to Figure 29.
The capacitance load of the analog input Pin is 4 pF to the analog supplies (AVSS, AVDD).
Full-scale setpoints may be calculated according to the following algorithm (V
–F
= (V
S
= (V
+F
S
= V
V
SPAN
may be internally or externally generated):
REF
– V
+ V
REF
REF
/2)
/2)
REF
REF
REF
REV. D
AD9201
0.1mF10mF
0.1mF
0.1mF
COMMON
MODE
VOLTAGE
0.1mF
10mF
R1
R2
I OR QREFT
I OR QREFB
IINA
IINB
AD9201
QINB
QINA
REFSENSE
VREF
QINA
QINB
IINA
IINB
AD9201
DVDD
I OR QREFT
I OR QREFB
AVDD
0.1mF
10mF
0.1mF10mF
AD9201
0.1mF
0.1mF
0.1mF10mF
V ANALOG V DIGITAL
The AD9201 can accommodate a variety of input spans be­tween 1 V and 2 V. For spans of less than 1 V, expect a propor­tionate degradation in SNR . Use of a 2 V span will provide the best noise performance. 1 V spans will provide lower distortion when using a 3 V analog supply. Users wishing to run with larger full-scales are encouraged to use a 5 V analog supply (AVDD).
Single-Ended Inputs: For single-ended input signals, the signal is applied to one input pin and the other input pin is tied to a midscale voltage. This midscale voltage defines the center of the full-scale span for the input signal.
EXAMPLE: For a single-ended input range from 0 V to 1 V applied to IINA, we would configure the converter for a 1 V reference (See Figure 17) and apply 0.5 V to IINB.
1V
INPUT
MIDSCALE
VOLTAGE
= 0.5V
5kV 5kV
0V
IINA
I OR QREFT
0.1mF
I OR QREFB
10mF
IINB
0.1mF
AD9201
VREF
REFSENSE
0.1mF
10mF
0.1mF
10mF
0.1mF
AC Coupled Inputs
If the signal of interest has no dc component, ac coupling can be easily used to define an optimum bias point. Figure 18 illus­trates one recommended configuration. The voltage chosen for the dc bias point (in this case the 1 V reference) is applied to
both IINA and IINB pins through 1 k resistors (R1 and R2).
IINA is coupled to the input signal through Capacitor C1, while IINB is decoupled to ground through Capacitor C2 and C3.
Transformer Coupled Inputs
Another option for input ac coupling is to use a transformer. This not only provides dc rejection, but also allows truly differ­ential drive of the AD9201’s analog inputs, which will provide the optimal distortion performance. Figure 19 shows a recom­mended transformer input drive configuration. Resistors R1 and R2 define the termination impedance of the transformer coupling. The center tap of the transformer secondary is tied to the com­mon-mode reference, establishing the dc bias point for the ana­log inputs.
Figure 17. Example Configuration for 0 V–1 V Single­Ended Input Signal
Note that since the inputs are high impedance, this reference level can easily be generated with an external resistive divider with large resistance values (to minimize power dissipation). A decoupling capacitor is recommended on this input to minimize the high frequency noise-coupling onto this pin. Decoupling should occur close to the ADC.
Differential Inputs
Use of differential input signals can provide greater flexibility in input ranges and bias points, as well as offering improvements in distortion performance, particularly for high frequency input signals. Users with differential input signals will probably want to take advantage of the differential input structure.
1.5V
0.5V
INPUT
C2
1.0mF
C1
R1 1kV
C3
0.1mF
IINA
IINB
AD9201
VREF REFSENSE
ANALOG
Figure 18. Example Configuration for 0.5 V–1.5 V ac Coupled Single-Ended Inputs
REV. D
REFT
REFB
0.1mF
0.1mF
10mF
0.1mF
Figure 19. Example Configuration for Transformer Coupled Inputs
Crosstalk: The internal layout of the AD9201, as well as its pinout, was configured to minimize the crosstalk between the two input signals. Users wishing to minimize high frequency crosstalk should take care to provide the best possible decoupling for input pins (see Figure 20). R and C values will make a pole dependant on antialiasing requirements. Decoupling is also required on reference pins and power supplies (see Figure 21).
Figure 20. Input Loading
Figure 21. Reference and Power Supply Decoupling
–9–
AD9201
I OR QREFT
I OR QREFB
VREF
0.1mF10mF
0.1mF
0.1mF
AD9201
REFSENSE
+
AVSS
0.1mF
1mF
R2
R1
1V
VREF = 1 +
R2 R1
+ –
1V
EXT
REFERENCE
AVDD
I OR QREFT
I OR QREFB
IINA
IINB
VREF
0.1mF10mF
0.1mF
0.1mF
0.1mF
AD9201
0.1mF
10mF
10mF
1V
0V
QINB
QINA
5kV
5kV
REFSENSE
1V 0V
REFERENCE AND REFERENCE BUFFER
The reference and buffer circuitry on the AD9201 is configured for maximum convenience and flexibility. An illustration of the equivalent reference circuit is show in Figure 26. The user can select from five different reference modes through appropriate pin-strapping (see Table I below). These pin strapping options cause the internal circuitry to reconfigure itself for the appropri­ate operating mode.
Table I. Table of Modes
Mode Input Span REFSENSE Pin Figure
1 V 1 V VREF 22 2 V 2 V AGND 23 Programmable 1 + (R1/R2) See Figure 24 External = External Ref AVDD 25
1 V Mode (Figure 22)—provides a 1 V reference and 1 V input full scale. Recommended for applications wishing to optimize high frequency performance, or any circuit on a supply voltage of less than 4 V. The part is placed in this mode by shorting the REFSENSE pin to the VREF pin.
1V
0V
5kV
0.1mF
10mF
5kV
10mF
0.1mF
1V
IINA
IINB
AD9201
VREF REFSENSE
I OR QREFT
I OR QREFB
QINA QINB
1V
0V
0.1mF
0.1mF10mF
0.1mF
Externally Set Voltage Mode (Figure 24)—this mode uses the on-chip reference, but scales the exact reference level though the use of an external resistor divider network. VREF is wired to the top of the network, with the REFSENSE wired to the tap point in the resistor divider. The reference level (and input full
scale) will be equal to 1 V × (R1 + R2)/R1. This method can be
used for voltage levels from 0.7 V to 2.5 V.
Figure 24. Programmable Reference
External Reference Mode (Figure 25)—in this mode, the on­chip reference is disabled, and an external reference is applied to the VREF pin. This mode is achieved by tying the REFSENSE pin to AVDD.
Figure 22. 0 V to 1 V Input
2 V Mode (Figure 23)—provides a 2 V reference and 2 V input full scale. Recommended for noise sensitive applications on 5 V supplies. The part is placed in 2 V reference mode by grounding (shorting to AVSS) the REFSENSE pin.
2V
0V
5kV
IINA
IINB
AD9201
VREF
REFSENSE
0.1mF
10mF
5kV
10mF
0.1mF
Figure 23. 0 V to 2 V Input
QINA QINB
I OR QREFT
I OR QREFB
2V 0V
0.1mF
0.1mF10mF
0.1mF
–10–
Figure 25. External Reference
Reference Buffer—The reference buffer structure takes the voltage on the VREF pin and level-shifts and buffers it for use by various subblocks within the two A/D converters. The two converters share the same reference buffer amplifier to maintain the best possible gain match between the two converters. In the interests of minimizing high frequency crosstalk, the buffered references for the two converters are separately decoupled on the IREFB, IREFT, QREFB and QREFT pins, as illustrated in Figure 26.
REV. D
0.1mF
ADC
17
16
1kV
VREF
AD8051
3
2
50V
1kV
1kV
6
22V
22V
0.33mF
0.01mF
10pF
10pF
24V
–120
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
0
10
0.0E+0 2.0E+6
1.0E+6
4.0E+6 6.0E+6 8.0E+6 10.0E+6
3.0E+6 5.0E+6 7.0E+6 9.0E+6
FUND
2ND 3RD
4TH
5TH
6TH
7TH
8TH
AD9201
ADC
CORE
0.1mF
0.1mF
10mF
IREFT
0.1mF10mF
QREFT
0.1mF
10mF 0.1mF
REFSENSE
IREFB
VREF
AVSS
10kV
10kV
1V
INTERNAL CONTROL
LOGIC
QREFB
0.1mF
AD9201
Figure 26. Reference Buffer Equivalent Circuit and Exter­nal Decoupling Recommendation
For best results in both noise suppression and robustness against crosstalk, the 4 capacitor buffer decoupling arrangement shown in Figure 26 is recommended. This decoupling should feature chip capacitors located close to the converter IC. The capacitors are connected to either IREFT/IREFB or QREFT/ QREFB. A connection to both sides is not required.
DRIVING THE AD9201
Figure 27 illustrates the use of an AD8051 to drive the AD9201. Even though the AD8051 is specified with 3 V and 5 V power,
the best results are obtained at ±5 V power. The ADC input
span is 2 V.
Figure 27.
Figure 28. AD8051/AD9201 Performance
REV. D
–11–
AD9201
COMMON-MODE PERFORMANCE
Attention to the common-mode point of the analog input volt­age can improve the performance of the AD9201. Figure 29 illustrates THD as a function of common-mode voltage (center point of the analog input span) and power supply.
–30
–35
–40
–45
–50
–55
THD – dB
–60
–65
–70
–75 –80
–0.5 1.50 0.5 1.0
COMMON-MODE LEVEL – V
2V SPAN
1V SPAN
a. Differential Input, 3 V Supplies
Inspection of the curves will yield the following conclusions:
1. An AD9201 running with AVDD = 5 V is the easiest to drive.
2. Differential inputs are the most insensitive to common-mode voltage.
3. An AD9201 powered by AVDD = 3 V and a single ended input, should have a 1 V span with a common-mode voltage of 0.75 V.
–10
2V SPAN
–20
–30
–40
–50
THD – dB
–60
–70
–80
–0.5 0 0.5 1.0
COMMON-MODE LEVEL – V
1V SPAN
1.5
c. Single-Ended Input, 3 V Supplies
–30 –35
–40
–45
–50
–55
THD – dB
–60
–65
–70
1V SPAN –75 –80
–0.5 2.50 0.5 1.0
COMMON-MODE LEVEL – V
b. Differential Input, 5 V Supplies
Figure 29. THD vs. CML Input Span and Power Supply (Analog Input = 1 MHz)
2V SPAN
1.5 2.0
–10
–20
–30
–40
–50
THD – dB
–60
–70
–80
–0.5 2.50 0.5 1.0
COMMON-MODE LEVEL – V
d. Single-Ended Input, 5 V Supplies
2V SPAN
1V SPAN
1.5 2.0
–12–
REV. D
AD9201
CLOCK
DATA
I LATCH
CLOCK
DATA
Q LATCH
CLK
DATA
OUT
SELECT
I
PROCESSING
Q
PROCESSING
CLOCK
SOURCE
0
90
DSP
OR
ASIC
10
CARRIER
FREQUENCY
NYQUIST
FILTERS
TO MIXER
QUADRATURE
MODULATOR
AD9761
IOUT
QOUT
DIGITAL INPUTS AND OUTPUTS
Each of the AD9201 digital control inputs, CHIP SELECT, CLOCK, SELECT and SLEEP are referenced to AVDD and AVSS. Switching thresholds will be AVDD/2.
The format of the digital output is straight binary. A low power mode feature is provided such that for STBY = HIGH and the clock disabled, the static power of the AD9201 will drop below 22 mW.
CLOCK INPUT
The AD9201 clock input is internally buffered with an inverter powered from the AVDD pin. This feature allows the AD9201 to accommodate either +5 V or +3.3 V CMOS logic input sig­nal swings with the input threshold for the CLK pin nominally at AVDD/2.
The pipelined architecture of the AD9201 operates on both rising and falling edges of the input clock. To minimize duty cycle variations the logic family recommended to drive the clock input is high speed or advanced CMOS (HC/HCT, AC/ACT) logic. CMOS logic provides both symmetrical voltage threshold levels and sufficient rise and fall times to support 20 MSPS operation. Running the part at slightly faster clock rates may be possible, although at reduced performance levels. Conversely, some slight performance improvements might be realized by clocking the AD9201 at slower clock rates.
The power dissipated by the output buffers is largely propor­tional to the clock frequency; running at reduced clock rates provides a reduction in power consumption.
DIGITAL OUTPUTS
Each of the on-chip buffers for the AD9201 output bits (D0–D9) is powered from the DVDD supply pin, separate from AVDD. The output drivers are sized to handle a variety of logic families while minimizing the amount of glitch energy generated. In all cases, a fan-out of one is recommended to keep the capacitive load on the output data bits below the specified 20 pF level.
For DVDD = 5 V, the AD9201 output signal swing is compat­ible with both high speed CMOS and TTL logic families. For TTL, the AD9201 on-chip, output drivers were designed to support several of the high speed TTL families (F, AS, S). For applications where the clock rate is below 20 MSPS, other TTL families may be appropriate. For interfacing with lower voltage CMOS logic, the AD9201 sustains 20 MSPS operation with DVDD = 3 V. In all cases, check your logic family data sheets for compatibility with the AD9201’s Specification table.
A 2 ns reduction in output delays can be achieved by limiting the logic load to 5 pF per output line.
SELECT
When the select pin is held LOW, the output word will present the “Q” level. When the select pin is held HIGH, the “I” level will be presented to the output word (see Figure 1).
The AD9201’s select and clock pins may be driven by a com­mon signal source. The data will change in 5 ns to 11 ns after the edges of the input pulse. The user must make sure the inter­face latches have sufficient hold time for the AD9201’s delays (see Figure 30).
Figure 30. Typical De-Mux Connection
APPLICATIONS USING THE AD9201 FOR QAM DEMODULATION
QAM is one of the most widely used digital modulation schemes in digital communication systems. This modulation technique can be found in both FDMA as well as spread spectrum (i.e., CDMA) based systems. A QAM signal is a carrier frequency which is both modulated in amplitude (i.e., AM modulation) and in phase (i.e., PM modulation). At the transmitter, it can be generated by independently modulating two carriers of iden-
tical frequency but with a 90° phase difference. This results in
an inphase (I) carrier component and a quadrature (Q) carrier
component at a 90° phase shift with respect to the I component.
The I and Q components are then summed to provide a QAM signal at the specified carrier or IF frequency. Figure 31 shows a typical analog implementation of a QAM modulator using a
dual 10-bit DAC with 2× interpolation, the AD9761. A QAM
signal can also be synthesized in the digital domain thus requir­ing a single DAC to reconstruct the QAM signal. The AD9853 is an example of a complete (i.e., DAC included) digital QAM modulator.
THREE-STATE OUTPUTS
The digital outputs of the AD9201 can be placed in a high impedance state by setting the CHIP SELECT pin to HIGH. This feature is provided to facilitate in-circuit testing or evaluation.
REV. D
Figure 31. Typical Analog QAM Modulator Architecture
–13–
AD9201
DATA
ANALOG
GROUND
DIGITAL
GROUND
LOGIC
ADC
AIN BIN
RF
GROUND
At the receiver, the demodulation of a QAM signal back into its separate I and Q components is essentially the modulation pro­cess explain above but in the reverse order. A common and traditional implementation of a QAM demodulator is shown in Figure 32. In this example, the demodulation is performed in the analog domain using a dual, matched ADC and a quadra­ture demodulator to recover and digitize the I and Q baseband signals. The quadrature demodulator is typically a single IC containing two mixers and the appropriate circuitry to generate
the necessary 90° phase shift between the I and Q mixers’ local
oscillators. Before being digitized by the ADCs, the mixed down baseband I and Q signals are filtered using matched ana­log filters. These filters, often referred to as Nyquist or Pulse­Shaping filters, remove images-from the mixing process and any out-of-band. The characteristics of the matching Nyquist filters are well defined to provide optimum signal-to-noise (SNR) performance while minimizing intersymbol interference. The ADC’s are typically simultaneously sampling their respective inputs at the QAM symbol rate or, most often, at a multiple of it if a digital filter follows the ADC. Oversampling and the use of digital filtering eases the implementation and complexity of the analog filter. It also allows for enhanced digital processing for both carrier and symbol recovery and tuning purposes. The use of a dual ADC such as the AD9201 ensures excellent gain, offset, and phase matching between the I and Q channels.
I
ADC
DSP
OR
ASIC
Q
ADC
DUAL MATCHED
ADC
CARRIER
FREQUENCY
NYQUIST
FILTERS
LO
DEMODULATOR
90°C
QUADRATURE
FROM PREVIOUS STAGE
Figure 32. Typical Analog QAM Demodulator
GROUNDING AND LAYOUT RULES
As is the case for any high performance device, proper ground­ing and layout techniques are essential in achieving optimal performance. The analog and digital grounds on the AD9201 have been separated to optimize the management of return currents in a system. Grounds should be connected near the ADC. It is recommended that a printed circuit board (PCB) of at least four layers, employing a ground plane and power planes, be used with the AD9201. The use of ground and power planes offers distinct advantages:
1. The minimization of the loop area encompassed by a signal and its return path.
2. The minimization of the impedance associated with ground and power paths.
3. The inherent distributed capacitor formed by the power plane, PCB insulation and ground plane.
These characteristics result in both a reduction of electro­magnetic interference (EMI) and an overall improvement in performance.
It is important to design a layout that prevents noise from cou­pling onto the input signal. Digital signals should not be run in parallel with the input signal traces and should be routed away from the input circuitry. Separate analog and digital grounds should be joined together directly under the AD9201 in a solid ground plane. The power and ground return currents must be carefully managed. A general rule of thumb for mixed signal layouts dictates that the return currents from digital circuitry should not pass through critical analog circuitry.
Transients between AVSS and DVSS will seriously degrade performance of the ADC.
If the user cannot tie analog ground and digital ground together at the ADC, he should consider the configuration in Figure 33.
LOGIC
DV
D
SUPPLY
DIGITAL
LOGIC
ICs
GND
D
V
IN
A
A
D
A A
ADC
IC
= ANALOG = DIGITAL
AVDD
ANALOG
CIRCUITS
A
DVDD
C
STRAY
DIGITAL
CIRCUITS
C
STRAY
I
A
B
I
D
DVSSAVSS
AA
Figure 33. Ground and Power Consideration
Another input and ground technique is shown in Figure 34. A separate ground plane has been split for RF or hard to manage signals. These signals can be routed to the ADC differentially or single ended (i.e., both can either be connected to the driver or RF ground). The ADC will perform well with several hundred mV of noise or signals between the RF and ADC analog ground.
-
Figure 34. RF Ground Scheme
–14–
REV. D
EVALUATION BOARD
The AD9201 evaluation board is shipped “ready to run.” Power and signal generators should be connected as shown in Figure 35. Then the user can observe the performance of the Q channel. If the user wants to observe the I channel, then he should install a jumper at JP22 Pins 1 and 2. If the user wants to toggle between I and Q channels, then a CMOS level pulse train should be applied to the “strobe” jack after appropriate jumper connections.
AD9201
SYNTHESIZER
SYNTHESIZER
1MHz 1Vp-p
+3V +3V
20MHz
2Vp-p
ANTI-
ALIAS
FILTER
AGND
CLOCK
Q IN
AVDD
DGND1
AD9201
DVDD
DGND2
Figure 35. Evaluation Board Connections
+5V
DRVDD
P1
DSP
EQUIPMENT
REV. D
–15–
AD9201
– 9201EB –
+C5 +C36
C4
C35
C54
C55
C14 C17 C23 C27
R50 R51 C14
C24 R52 R53
C53
C50 C51
C52
C20 C22
C29
(NOT TO SCALE)
Figure 36. Evaluation Board Solder-Side Silkscreen
REV
(NOT TO SCALE)
Figure 37. Evaluation Board Component-Side Layout
–16–
REV. D
(NOT TO SCALE)
AD9201
Figure 38. Evaluation Board Ground Plane Layout
REV. D
(NOT TO SCALE)
Figure 39. Evaluation Board Solder-Side Layout
–17–
AD9201
AGND
AVDD
AGND
I_IN STROBE AGND AVDD CLOCK DGND1 DVDD DGND2 DBVDD
BJ3
C38
J6
C19
C24 +
V8
R39
L5
DGND
JP16
BJ4
C45
C44
R36
TP4
C2
C9
C30
C49 +
C40
J1 J5
R30
R23
TP3
Q_IN
R8
J4
BJ2
R37 R13 R11
JP3
T1
R2
C1 JP2
C3
J3
JP10
T2
R34
C34
C37
JP12
V6
C32
D1
R9
R12
BJ1
R38
C42
JP22
JP21
R4
R1
JP1
JP7 JP9
R40
R35
JP11
C31 +
C21
C12
+
L2
C41
C33
R31
JP13
4 TP2
TP1
4
JP14
TP5 TP6
R16
R17
R24
+
C11
V3
JP15
R33
R32
C15 +
+ C25
JP4
C8
TP7
V4
R18
+
R14
JP6
JP5
R6 R7 R10
BJ6
+ C43
L3
V1
C6
V2
C10
C48
JP19
C7
JP20
C13
(NOT TO SCALE)
Figure 40. Evaluation Board Component-Side Silkscreen
RN1
L4
JP17
RN2
BJ5
+ C46
C47
P1
DBVDD
(NOT TO SCALE)
Figure 41. Evaluation Board Power Plane Layout
–18–
REV. D
AD9201
STROBE
AVDD
15
16
17
18
19
20
21
22
23
24
25
26
27
28
AVDD
8
AD822
+
U3
ADJ_REF
AVDD
8
AD822
+
U6
1
J3
1
1
AVDD
1
1
DVDD
1
1
DRVDD
BBBBBBBBVCCB
NC1OEGND1
AAAAAAA
A
VCCA
T/R
GND2
GND3
U1
C2
0.1mF
1615212019181714242322
13
D5D6D7D8D9
DVDD
74LVXC4245
BBBD0D1D2D3D4VCCB
NC1OEGND1
AAAAAAA
A
VCCA
T/R
GND2
GND3
U2
C9
0.1mF
1920212018171614242322
13
D0D1D2
D3
DVDD
1
3
2
JP16
HDR3
1
3
2
JP15
HDR3
74AHC14DW74AHC14DW
74AHC14DW
AVDD
U8A
U8B
U8C
C38
0.1mF
1
2
3
4
5
6
DUTCLK
R39
R-S 50V
TP7
CON1
TP4
CON1
R-S TBDV
R36
CLK0
C33
0.1mF
AVDD
R31
500V
R32
POT_2kV
R33
500V
R38
R-S
50V
ADC_CLK
J6
BNC
74LVXC4245
D4
DRVDD
5436789101211
12
BCLK0
BD0
BD1
BD2
BD3
BD4
BD5
BD7
BD8
BD9
BD6
8934567101211
12
DRVDD
SLEEP
INA-1
INB-1
REFT-1
REFB-1
AVSS
REFSENSE
VREF
AVDD
REFB-Q
REFT-Q
INB-Q
INA-Q
CHIP-SELECT
DUTCLK
SELECT
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
DVDD
DVSS
TESTCHIP
14
13
12
11
10
9
8
7
6
5
4
3
D4D8
D7
D6
D5
D4
D3
D2
D1
D0
D9
31
30
4
2
29
28
3
6
2624228101220251827163214343340393638
37
13
11
9
7
5
1
33
23
21
19
17
15
P1
DRVDD
1
3
2
JP17
HDR3
RESISTOR
7PACK
1
2
3
4
5
6
1
2
3
4
5
6
14
13
12
11
10
9
14
13
12
11
10
9
CLK
OUT
CON40
74AHC14DW
U8F
13
12
74AHC14DW
U8E
11
10
74AHC14DW
U8D
9
8
C10
0.1mF
123
JP20
HDR3
1
3
2
JP19
HDR3
C7
0.1mF
C6
0.1mF
CLK0
C13
0.1mF
DUTDATA
[0...9]
DGND
DVDD
L3
FERRITE BEAD
C45
CAP_NP
C44
CAP_NP
C43
10_10V
DVDD
L4
FERRITE BEAD
C48
CAP_NP
C47
CAP_NP
C46
10_10V
DRVDD
DRVDD
BJ3
BANA
BJ4
BANA
BJ5
BANA
BJ6
BANA
AVDD
AVDD VCC
L2
FERRITE BEAD
C42
CAP_NP
C41
CAP_NP
C40
10_10V
J5
BNC
STROBE
R37
R-S 49.9V
RN1A
RN1B
RN1C
RN1D
RN1E
RN1F
RN2A
RN2B
RN2C
RN2D
RN2E
RN2F
J1
BNC
CH1IN
R2
R-S 50V
2
3
1
HDR3
JP3
T1
TRANSFORMER
CT
1234
6
PS
JP2
JUMPER
JP2
JUMPER
C1
0.1mF
C3
10_6V3
TP1
CON1
R1
R-S TBDV
TP2
CON1
DCIN1
AGND
R_VREF
1
2
3
4
JP13
HDR3
C54
1000pF
C5
10_6V3
C4
0.1V
R4
R-S 100V
MIDSCALE_IN
AD9201
NOT TO SCALE
DRVDD
D[0...9]
DRVDD
C29
CAP_NP
L5
FERRITE_BEAD
DVDD
C53
10pF
C52
10pF
C23
0.1mF
C25
CAP_P
C26
CAP_NP
C27
0.1mF
R52
10V
R53
10V
1
3
2
JP6
HDR3
AVDD
INA-Q
INB-Q
2
1
JP14
HDR4
3
4
R_VREF
TP6
CON1
C55
1000pF
C36
10_6V3
C35
0.1mF
R35
R-S 1V
TP5
CON1
JP11
JUMPER
J4
BNC
JUMPER
C34
0.1mF
C37
10_6V3
1
2
34
6
PS
T2
TRANSFORMER CT
R40
R-S 100V
3
1
2
JP10
HDR3
R34
R-S 50V
CHOIN
JP12
R30
1.5kV
R23
POT_10kV
C31
10_6V3
C32
0.1mF
R24
R-S 22V
R17
15kV
R16
5kV
C21
CAP_NP
ADJ_REF
D1
R8
5.49kV
DIODE_ZENER
R9
POT_10kV
R12
1.5kV
C12
0.1kV
C11
10_6V3
R10
R-S 10V
C8
CAP_NP
R7
15kV
R6
5kV
JP5
JUMPER
JP7
JUMPER
JP9
JUMPER
C24
10_10V
C19
10_10V
C20
0.1kV
C22
0.1kV
R18
R-S TBDV
R14
R-S TBDV
1
2
3
JP4
C16
CAP_NP
C15
CAP_P
C14
0.1mF C17
0.1mF
C50
10pF
C51
10pF
R51
10V
R50
10V
R11
1kV
DUTCLK
1
2
3
JP22
AVDD
HDR3
3
1
2
HDR3
R13
1kV
C30
CAP_NP
C49
10_10V
U4
TP3
CON1
APWRIN
GND
BJ1
BANA
BJ2
BANA
DPWRIN
DPWRIN
INA-1
INB-1
MIDSCALE_I
JP21
VREF
DCINO
AVDD
AVDD
R_VREF
REV. D
–19–
Figure 42. Evaluation Board
AD9201
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
28-Lead Shrink Small Outline Package (SSOP)
(RS-28)
0.407 (10.34)
0.397 (10.08)
28 15
0.311 (7.9)
0.301 (7.64)
141
0.212 (5.38)
0.205 (5.21)
C3116d–0–8/99
0.078 (1.98)
0.068 (1.73)
0.008 (0.203)
0.002 (0.050)
PIN 1
0.0256 (0.65)
BSC
0.015 (0.38)
0.010 (0.25)
SEATING
PLANE
0.07 (1.79)
0.066 (1.67)
0.009 (0.229)
0.005 (0.127)
8° 0°
0.03 (0.762)
0.022 (0.558)
–20–
PRINTED IN U.S.A.
REV. D
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