AD7626BCPZ Analog Devices Inc, AD7626BCPZ Datasheet
AD7626BCPZ
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AD7626BCPZ Summary of contents
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FEATURES Throughput: 10 MSPS SNR: 91.5 dB 16-bit no missing codes INL: ±0.45 LSB DNL: ±0.35 LSB Power dissipation: 136mW 32-lead LFCSP (5 mm × 5 mm) SAR architecture No latency/no pipeline delay 16-bit resolution with no missing codes Zero ...
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AD7626 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Timing Specifications .................................................................. 5 Timing Diagrams .......................................................................... 6 Absolute Maximum Ratings ............................................................ 7 Thermal ...
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SPECIFICATIONS VDD1 = 5 V; VDD2 = 2.5 V; VIO = 2.5 V; REF = 4.096 V; all specifications T Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Operating Input Voltage Common-Mode Input Range CMRR Input Current THROUGHPUT Complete Cycle ...
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AD7626 Parameter REFERENCE BUFFER REFIN Input Voltage Range REF Output Voltage Range Line Regulation EXTERNAL REFERENCE Voltage Range VCM PIN VCM Output VCM Error Output Impedance LVDS I/O (ANSI-644) Data Format Differential Output Voltage Common-Mode Output Voltage, V ...
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TIMING SPECIFICATIONS VDD1 = 5 V; VDD2 = 2.5 V; VIO = 2. 2.63 V; REF = 4.096 V; all specifications T Table 3. Parameter 1 Time Between Conversions CNV High Time CNV to D (MSB) Ready CNV ...
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AD7626 TIMING DIAGRAMS SAMPLE N t CNVH CNV– CNV+ ACQUISITION t CLK CLK– CLK+ t DCO DCO– DCO+ t CLKD D+ N – 1 D– SAMPLE N t CNVH CNV– CNV+ ACQUISITION t CLK 17 CLK– CLK CLKD ...
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ABSOLUTE MAXIMUM RATINGS Table 4. Parameter Analog Inputs/Outputs IN+, IN− to GND 1 2 REF to GND VCM, CAP2 to GND CAP1, REFIN to GND Supply Voltage VDD1 VDD2, VIO Digital Inputs to GND Digital Outputs to GND Input Current ...
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AD7626 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions 1 Pin No. Mnemonic Type Description 1 VDD1 P Analog 5 V Supply. Decouple the 5 V supply with a 100 nF capacitor. 2 VDD2 P Analog 2.5 V ...
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Pin No. Mnemonic Type Description 23 IN+ AI Differential Positive Analog Input. Referenced to and must be driven 180° out of phase with IN−. 24 GND P Ground. 25, 26, 28 CAP2 AO Connect all three CAP2 pins together ...
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AD7626 TYPICAL PERFORMANCE CHARACTERISTICS VDD1 = 5 V; VDD2 = 2.5 V; VIO = 2.5 V; REF = 4.096 V; all plots at 10 MSPS unless otherwise noted. FFT plots for 2 MHz, 3 MHz, and 5 MHz input tones ...
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INPUT FREQUENCY = 5.00656128MHz –0.5dB INPUT AMPLITUDE –20 SNR = 86.7dBFS SINAD = 83.2dBFS THD = –85.3dB SFDR = 86.1dB –40 64k SAMPLES –60 –80 SECOND HARMONIC –100 FOURTH HARMONIC –120 –140 –160 –180 0 0.5 1.0 1.5 2.0 ...
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AD7626 92.0 91.8 91.6 91.4 91.2 EXTERNAL REFERENCE 91.0 90.8 INTERNAL REFERENCE 90.6 90.4 90.2 90.0 –40 – TEMPERATURE (°C) Figure 17. SNR vs. Temperature (−0.5 dB, 20 kHz Input Tone) 0.35 0.30 0.25 0.20 0.15 0.10 ...
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SAMPLES STD DEVIATION = 0.4814 201,614 200,000 150,000 100,000 50,000 30,250 30,206 FEC8 FEC9 FECA FECB FECC CODE (HEX) Figure 23. Histogram of 262,144 Conversions Input at the Code Center (External Reference) ...
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AD7626 TERMINOLOGY Common-Mode Rejection Ratio (CMRR) CMRR is defined as the ratio of the power in the ADC output at full-scale frequency the power of a 100 mV p-p sine wave applied to the common-mode voltage of V ...
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THEORY OF OPERATION IN+ MSB 32,768C 16,384C REF (4.096V) GND 32,768C 16,384C MSB IN– CIRCUIT INFORMATION The AD7626 MSPS, high precision, power effi- cient, 16-bit ADC that uses SAR-based architecture to provide a performance of 91.5 dB ...
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AD7626 TRANSFER FUNCTIONS The AD7626 uses a 4.096 V reference. The AD7626 converts the differential voltage of the antiphase analog inputs (IN+ and IN−) into a digital output. The analog inputs, IN+ and IN−, require a 2.048 V common-mode voltage ...
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TYPICAL CONNECTION DIAGRAM V+ ADR434 ADR444 CAPACITOR ON OUTPUT FOR STABILITY VDD1 (5V) 100nF VDD2 (2.5V) 100nF 10nF 8 ADR280 10 µ F VIO 3 10kΩ 10kΩ CONTROL FOR ENABLE PINS VDD2 (2.5V) 100nF 4 CONVERSION CONTROL CMOS (CNV+ ONLY) ...
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AD7626 DRIVING THE AD7626 Differential Analog Input Source Figure 33 shows an ADA4899-1 driving each differential input to the AD7626. Single-Ended-to-Differential Driver For applications using unipolar analog signals, a single- ended-to-differential driver (as shown in Figure 32) allows for a ...
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R35 SINGLE-ENDED 499Ω ANALOG INPUT AC-COUPLED 50Ω SOURCE +7.25V 53.6Ω VDRV+ GND C 499Ω 12 50Ω 53.6Ω –2.5V GND 499Ω Figure 34. High Frequency Input Drive Circuit Using the ADA4932-1; Single-Ended-to Differential Configuration C22 C24 0.1µF 0.1µF GND VCM ...
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AD7626 VOLTAGE REFERENCE OPTIONS The AD7626 allows flexible options for creating and buffering the reference voltage. The AD7626 conversions refer to 4.096 V only. The various options creating this 4.096 V reference are controlled by the EN1 and EN0 pins ...
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Wake-Up Time from EN1= 0, EN0 = 0 The AD7626 powers down when EN1 and EN0 are both set to 0. Selecting the correct reference choice from power-down, the user sets EN1 and EN0 to the required value shown in ...
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AD7626 DIGITAL INTERFACE Conversion Control All analog-to-digital conversions are controlled by the CNV± signal. This signal can be applied in the form of a CNV+/CNV− LVDS signal can be applied in the form of a 2.5 V CMOS ...
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Self-Clocked Mode The digital operation of the AD7626 in self-clocked interface mode is shown in Figure 42. This interface mode reduces the number of traces between the ADC and the digital host to two LVDS pairs (CLK± and D±) or ...
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AD7626 APPLICATIONS INFORMATION LAYOUT, DECOUPLING, AND GROUNDING When laying out the printed circuit board (PCB) for the AD7626, follow the practices described in this section to obtain the maxi- mum performance from the converter. Exposed Paddle The AD7626 has an ...
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... SEATING PLANE ORDERING GUIDE 1 Model Temperature Range AD7626BCPZ −40°C to +85°C AD7626BCPZ-RL7 −40°C to +85°C 2 EVAL-AD7626EDZ 3 EVAL-CED1Z RoHS Compliant Part. 2 This board can be used as a standalone evaluation board or in conjunction with the EVAL-CEDIZ for evaluation/demonstration purposes. 3 This board allows the PC to control and communicate with all Analog Devices evaluation boards with model numbers ending with the ED designator ...
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AD7626 NOTES Rev Page ...
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NOTES Rev Page AD7626 ...
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AD7626 NOTES ©2009–2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07648-0-1/10(A) Rev Page ...