AD9238BCP40EB Analog Devices Inc, AD9238BCP40EB Datasheet
AD9238BCP40EB
Specifications of AD9238BCP40EB
AD9238BCP40EB Summary of contents
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FEATURES Integrated dual 12-bit ADC Single 3 V supply operation (2 3.6 V) SNR = 70 dB (to Nyquist, AD9238-65) SFDR = 80.5 dBc (to Nyquist, AD9238-65) Low power: 300 mW/channel at 65 MSPS Differential input with 500 ...
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AD9238 TABLE OF CONTENTS Specifications..................................................................................... 4 DC Specifications ......................................................................... 4 AC Specifications.......................................................................... 5 Digital Specifications ................................................................... 6 Switching Specifications .............................................................. 6 Absolute Maximum Ratings............................................................ 7 Explanation of Test Levels ........................................................... 7 ESD Caution.................................................................................. 7 Pin Configuration and Function Descriptions............................. 8 ...
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Rev. A Changes to DC Specifications ........................................................ 2 Changes to Switching Specifications ............................................. 3 Changes to AC Specifications......................................................... 4 Changes to Figure 1.......................................................................... 4 Changes to Ordering Guide............................................................ 5 Changes to TPCs 2, 3, and 6 ........................................................... ...
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AD9238 SPECIFICATIONS DC SPECIFICATIONS AVDD = 3 V, DRVDD = 2.5 V, maximum sample rate, CLK_A = CLK_B DCS enabled, unless otherwise noted. MIN MAX Table 1. Parameter Temp RESOLUTION Full ACCURACY No Missing Codes ...
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AC SPECIFICATIONS AVDD = 3 V, DRVDD = 2.5 V, maximum sample rate, CLK_A = CLK_B DCS enabled, unless otherwise noted. MIN MAX Table 2. Parameter SIGNAL-TO-NOISE RATIO (SNR 2.4 MHz INPUT f ...
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AD9238 DIGITAL SPECIFICATIONS AVDD = 3 V, DRVDD = 2.5 V, maximum sample rate, CLK_A = CLK_B DCS enabled, unless otherwise noted. MIN MAX Table 3. Parameter Temp LOGIC INPUTS High Level Input Voltage Full ...
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ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Pin Name ELECTRICAL AVDD DRVDD AGND AVDD Digital Outputs CLK, DCS, MUX_SELECT, SHARED_REF OEB, DFS VINA, VINB VREF SENSE REFB, REFT PDWN 2 ENVIRONMENTAL Operating Temperature Junction Temperature Lead Temperature (10 sec) Storage Temperature ...
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AD9238 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS AGND VIN+_A VIN–_A AGND AVDD REFT_A REFB_A VREF SENSE REFB_B REFT_B AVDD AGND VIN–_B VIN+_B AGND PIN ...
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Table 6. Pin Function Descriptions (64-Lead LQFP and 64-Lead LFCSP) Pin No. Mnemonic Description 1, 4, 13, 16 AGND Analog Ground. 2 VIN+_A Analog Input Pin (+) for Channel A. 3 VIN–_A Analog Input Pin (−) for Channel A. 5, ...
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AD9238 TERMINOLOGY Aperture Delay SHA performance measured from the rising edge of the clock input to when the input signal is held for conversion. Aperture Jitter The variation in aperture delay for successive samples, which is manifested as noise on ...
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TYPICAL PERFORMANCE CHARACTERISTICS AVDD, DRVDD = 3 25° –20 –40 –60 SECOND HARMONIC –80 CROSSTALK –100 –120 FREQUENCY (MHz) Figure 4. Single-Tone FFT of Channel A Digitizing f While ...
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AD9238 100 –35 –30 –25 –20 –15 INPUT AMPLITUDE (dBFS) Figure 10. AD9238-65 Single-Tone SNR/SFDR vs. AIN with f 100 90 80 SNR SFDR 70 SNR SNR –35 –30 –25 –20 ...
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FREQUENCY (MHz) Figure 16. Dual-Tone FFT with MHz and –20 –40 –60 –80 –100 –120 FREQUENCY ...
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AD9238 74 72 SINAD –20 70 SINAD – CLOCK FREQUENCY Figure 22. SINAD vs. FS with Nyquist Input 95 DCS ON (SFDR DCS OFF (SFDR DCS OFF (SINAD ...
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EQUIVALENT CIRCUITS AVDD VIN+_A, VIN–_A, VIN+_B, VIN–_B Figure 28. Equivalent Analog Input Circuit DRVDD Figure 29. Equivalent Digital Output Circuit AVDD CLK_A, CLK_B DCS, DFS, MUX_SELECT, SHARED_REF Figure 30. Equivalent Digital Input Circuit Rev Page ...
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AD9238 THEORY OF OPERATION The AD9238 consists of two high performance ADCs that are based on the AD9235 converter core. The dual ADC paths are independent, except for a shared internal band gap reference source, VREF. Each of the ADC ...
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The minimum common-mode input level allows the AD9238 to accommodate ground-referenced inputs. Although optimum performance is achieved with a differential input, a single- ended source may be driven into VIN+ or VIN−. In this configuration, one input accepts the signal, ...
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AD9238 (by gating, dividing, or other methods), it should be retimed by the original clock at the last step. POWER DISSIPATION AND STANDBY MODE The power dissipated by the AD9238 is proportional to its sampling rates. The digital (DRVDD) power ...
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DATA FORMAT The AD9238 data output format can be configured for either twos complement or offset binary. This is controlled by the data format select pin (DFS). Connecting DFS to AGND produces offset binary output data. Conversely, connecting DFS to ...
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AD9238 External Reference Operation The use of an external reference may be necessary to enhance the gain accuracy of the ADC or to improve thermal drift characteristics. When multiple ADCs track one another, a single reference (internal or external) may ...
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AD9238 LQFP EVALUATION BOARD The evaluation board supports both the AD9238 and AD9248 and has five main sections: clock circuitry, inputs, reference circuitry, digital control logic, and outputs. A description of each section follows. Table 8 shows the jumper settings ...
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AD9238 Table 8. PCB Jumpers Normal JP Description Setting Comment 1 Reference Out 1 V Reference Mode 2 Reference Reference Mode 3 Reference Out 1 V Reference Mode 4 Reference Out 1 V Reference Mode 5 Reference ...
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LQFP EVALUATION BOARD BILL OF MATERIALS (BOM) Table 10. No. Quantity Reference Designator 1 18 C1, C2, C11, C12, C27, C28, C33, C34, C50, C51, C73 to C76, C87 to C90 C10, C29 to C31, C56, ...
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AD9238 LQFP EVALUATION BOARD SCHEMATICS Figure 39. Evaluation Board Schematic Rev Page ...
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Figure 40. Evaluation Board Schematic (Continued) Rev Page AD9238 ...
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AD9238 Figure 41. Evaluation Board Schematic (Continued) Rev Page ...
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C75 C3 C10 C9 C8 10µF 0.1µF 0.1µF 0.1µF 0.1µF 6. DATACLKA 19 U10 G2 74VHC541 1 RP9 22Ω RP9 22Ω OTRA RP9 22Ω DA13 4 RP9 ...
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AD9238 LQFP PCB LAYERS Figure 43. PCB Top Side Silkscreen Rev Page ...
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Figure 44. PCB Top Layer Rev Page AD9238 ...
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AD9238 Figure 45. PCB Ground Plane Rev Page ...
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Figure 46. PCB Split Power Plane Rev Page AD9238 ...
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AD9238 Figure 47. PCB Bottom Layer Rev Page ...
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Figure 48. PCB Bottom Silkscreen Rev Page AD9238 ...
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AD9238 1 DUAL ADC LFCSP PCB The PCB requires a low jitter clock source, analog sources, and power supplies. The PCB interfaces directly with ADI’s standard dual-channel data capture board (HSC-ADC-EVAL-DC), which together with ADI’s ADC Analyzer™ software allows for ...
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LFCSP EVALUATION BOARD BILL OF MATERIALS (BOM) Table 13. No. Quantity Reference Designator C2, C5, C7, C9, C10, C22, C36 3 44 C4, C6, C8, C11 to C15, C20, C21, C24 to C27, C29 ...
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AD9238 LFCSP PCB SCHEMATICS ENCA D7A D7_A 49 D8A D8_A 50 D9A D9_A 51 DRVDD2 52 DRGND2 53 D10A D10_A 54 D11A D11_A 55 D12A D12_A 56 D13A D13_A 57 OTRA OTR_A 58 OEB_A 59 PDWN_A 60 MUX_SEL 61 SH_REF ...
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Figure 50. PCB Schematic ( Rev Page AD9238 ...
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AD9238 Figure 51. PCB Schematic ( Rev Page ...
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LFCSP PCB LAYERS Figure 52. PCB Top-Side Silkscreen Rev Page AD9238 ...
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AD9238 Figure 53. PCB Top-Side Copper Routing Rev Page ...
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Figure 54. PCB Ground Layer Rev Page AD9238 ...
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AD9238 Figure 55. PCB Split Power Plane Rev Page ...
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Figure 56. PCB Bottom-Side Copper Routing Rev Page AD9238 ...
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AD9238 THERMAL CONSIDERATIONS The AD9238 LFCSP has an integrated heat slug that improves the thermal and electrical properties of the package when locally attached to a ground plane at the PCB. A thermal (filled) via array to a ground plane ...
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OUTLINE DIMENSIONS 1.45 1.40 1.35 0.15 SEATING 0.05 PLANE VIEW A ROTATED 90° CCW 9.00 BSC SQ PIN 1 INDICATOR TOP VIEW 1.00 12° MAX 0.85 0.80 SEATING PLANE 0.75 1.60 0.60 MAX 0. PIN 1 0.20 0.09 ...
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AD9238 ORDERING GUIDE Model Temperature Range AD9238BST-20 –40°C to +85°C AD9238BSTRL-20 –40°C to +85°C 1 AD9238BSTZ-20 –40°C to +85°C 1 AD9238BSTZRL-20 –40°C to +85°C 1 AD9238BSTZ-20EB AD9238BST-40 –40°C to +85°C AD9238BSTRL-40 –40°C to +85°C 1 AD9238BSTZ-40 –40°C to +85°C 1 ...
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NOTES Rev Page AD9238 ...
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AD9238 NOTES ©2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C02640–0–4/05(B) Rev Page ...