AD7988-1 Analog Devices, AD7988-1 Datasheet
AD7988-1
Specifications of AD7988-1
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AD7988-1 Summary of contents
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... Data Sheet FEATURES Low power dissipation AD7988-5: 3 500 kSPS AD7988-1: 700 μW @ 100 kSPS 16-bit resolution with no missing codes Throughput: 100 kSPS/500 kSPS options INL: ±0.6 LSB typical, ±1.25 LSB maximum SINAD: 91 kHz THD: −114 kHz Pseudo differential analog input range ...
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... AD7988-1/AD7988-5 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Typical Application Diagram .......................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Timing Specifications .................................................................. 5 Absolute Maximum Ratings ............................................................ 7 ESD Caution .................................................................................. 7 Pin Configurations and Function Descriptions ........................... 8 Terminology ...................................................................................... 9 Typical Performance Characteristics ........................................... 10 Theory of Operation ...................................................................... 14 Circuit Information .................................................................... 14 Converter Operation .................................................................. 14 Typical Connection Diagram.................................................... 15 REVISION HISTORY 2/12— ...
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... REF kHz 2 REF kHz kHz kHz REF kHz 2 REF Rev Page AD7988-1/AD7988-5 Min Typ Max Unit 16 Bits REF −0 0.1 V REF −0.1 +0 See the Analog Inputs section ...
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... SOURCE POWER SUPPLIES VDD VIO Specified performance VIO Range Standby Current VDD and VIO = 2.5 V, 25° AD7988-1 Power Dissipation 10 kSPS throughput 100 kSPS throughput AD7988-5 Power Dissipation 500 kSPS throughput Energy per Conversion TEMPERATURE RANGE Specified Performance MIN With all digital inputs forced to VIO or GND as required ...
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... SCK t SCK t SCKL t SCKH t HSDO t DSDO DIS t SSDICNV t HSDICNV t HSDICNV t SSCKCNV t HSCKCNV t SSDISCK t HSDISCK Rev Page AD7988-1/AD7988-5 Min Typ Max Unit 100 kHz 9.5 μs 500 ns 10 μs 500 kHz 1.6 μs 400 ns 2 μs 500 ns 10 ...
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... AD7988-1/AD7988-5 500µ SDO C L 20pF 500µ Figure 2. Load Circuit for Digital Interface Timing Y% VIO 1 X% VIO t DELAY FOR VIO ≤ 3.0V AND Y = 10; FOR VIO > 3. 70, AND MINIMUM V AND MAXIMUM V USED. SEE DIGITAL INPUTS ...
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... V or ±130 mA REF 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. ESD CAUTION Rev Page AD7988-1/AD7988-5 ...
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... AI = analog input digital input digital output, and P = power. VIO SDI SCK SDO CNV range is from 2 5 referred to the GND pin. The GND pin REF . REF Rev Page Data Sheet REF 1 10 VIO AD7988-1/ VDD 2 9 SDI AD7988-5 IN SCK TOP VIEW IN– SDO ...
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... CNV input and when the input signal is held for a conversion. Transient Response Transient response is the time required for the ADC to accurately acquire its input after a full-scale step function is applied. N /Peak-to-Peak Noise) Rev Page AD7988-1/AD7988 /RMS Input Noise) 2 ...
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... SNR = 86.7dB THD = –110.4dB –40 SFDR = 103.9dB SINAD = 86.6dB –60 –80 –100 –120 –140 –160 –180 FREQUENCY (kHz) Figure 9. AD7988-1 FFT Plot 2.5 V REF 1.25 POSITIVE INL: +0.40 LSB NEGATIVE INL: –0.35 LSB 1.00 0.75 0.50 0. 16384 32768 49152 CODE Figure 10. Integral Nonlinearity vs. Code ...
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... V Figure 17. Histogram Input at the Code Center, V REF Rev Page AD7988-1/AD7988-5 50970 45198 18848 12424 1217 2290 7FFA 7FFB 7FFC 7FFD 7FFE 7FFF 8000 8001 8002 8003 8004 8005 8006 CODE IN HEX 2 ...
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... TEMPERATURE (°C) Figure 21. SNR vs. Temperature I VDD I REF I VIO 0 2.425 2.475 2.525 2.575 VDD VOLTAGE (V) Figure 22. Operating Currents vs. Supply (AD7988-5) I VDD I REF I VIO 0 2.375 2.425 2.475 2.525 2.575 VDD VOLTAGE (V) Figure 23. Operating Currents vs. Supply (AD7988-1) 105 125 2.625 2.625 ...
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... Rev Page AD7988-1/AD7988-5 0.14 I VDD 0.12 0.10 008 0.06 I REF 0.04 I VIO 0.02 0 –55 –35 – TEMPERATURE (°C) Figure 27. Operating Currents vs. Temperature (AD7988- VDD VIO –55 –35 – TEMPERATURE (°C) Figure 28. Power-Down Currents vs. Temperature 85 105 ...
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... AD7988-1/AD7988-5 devices are fast, low power, single- supply, precise 16-bit ADCs that use a successive approximation architecture. The AD7988-1 is capable of converting 100,000 samples per second (100 kSPS), whereas the AD7988-5 throughput of 500 kSPS, and they power down between conversions. When operating at 10 kSPS, for example, the ADC consumes 70 µ ...
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... REF 2 10µF 20Ω REF VDD IN+ 2.7nF AD7988-1/ AD7988-5 4 IN– GND Figure 31. Typical Application Diagram with Multiple Supplies Rev Page AD7988-1/AD7988-5 Analog Input Digital Output Code (Hex) REF 4.999924 V FFFF 1 2.500076 V 8001 2.5 V 8000 2.499924 V 7FFF 76.3 µV 0001 ...
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... AD7988-1/AD7988-5 ANALOG INPUTS Figure 32 shows an equivalent circuit of the input structure of the AD7988-x. The two diodes, D1 and D2, provide ESD protection for the analog inputs, IN+ and IN−. Care must be taken to ensure that the analog input signal never exceeds the supply rails by more than 0 ...
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... SDI and CNV are connected together, the chain mode is selected. The user must time out the maximum conversion time prior to readback. 100 1k Rev Page AD7988-1/AD7988-5 powers down automatically at the end of each AD7988-x has a reduced number of pins, it offers ...
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... After the 16th SCK falling edge or when CNV goes high, whichever is earlier, SDO returns to high impedance. enters the CONVERT DIGITAL HOST CNV VIO AD7988-1/ SDI SDO DATA IN AD7988-5 SCK CLK Figure 34. 3-Wire CS Mode Connection Diagram ...
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... SCKL HSDO SCKH t DSDO D15 D14 D13 D1 D0 Figure 37. 4-Wire CS Mode Serial Interface Timing Rev Page AD7988-1/AD7988-5 AD7988-x CS2 CS1 CONVERT DIGITAL HOST SDO DATA IN CLK D15 D14 D1 enters the AD7988-x t DIS ...
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... SCK falling edge allows a faster reading rate and, consequently, more AD7988-x has an acceptable hold time. The maximum conversion rate may be reduced due to the total readback time. CNV AD7988-1/ SDO SDI AD7988-5 B SCK Figure 38. Chain Mode Connection Diagram ...
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... AD7988-x AD7988-x is Figure 43. Example Layout of the Rev Page AD7988-1/AD7988-5 AD7988-x voltage reference input, REF, has a dynamic input and connected using short and wide traces to AD7988-x (EVAL-AD7988- AD7988-1/ AD7988-5 Figure 42. Example Layout of the AD7988-x (Top Layer) AD7988-x (Bottom Layer) devices. ...
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... AD7988-1/AD7988-5 OUTLINE DIMENSIONS IDENTIFIER PIN 1 INDEX AREA 0.80 0.75 0.70 SEATING PLANE 3.10 3.00 2. 5.15 3.10 4.90 3.00 4.65 1 2.90 5 PIN 1 0.50 BSC 0.95 15° MAX 0.85 1.10 MAX 0.75 0.15 0.23 6° 0.30 0.05 0.13 0° 0.15 COPLANARITY 0.10 COMPLIANT TO JEDEC STANDARDS MO-187-BA Figure 44.10-Lead Mini Small Outline Package [MSOP] (RM-10) Dimensions shown in millimeters 3.10 3.00 SQ 2.90 6 0.50 0.40 0.30 5 TOP VIEW BOTTOM VIEW 0.05 MAX 0.02 NOM ...
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... QFN (LFCSP_WD) −40°C to +125°C Reel, 1,500 10-Lead QFN (LFCSP_WD) Evaluation Board with AD7988-5 Populated; Use for Evaluation of Both AD7988-1 and AD7988-5. System Demonstration Board, Used as a Controller Board for Data Transfer via USB Interface to PC. EVAL-SDZ-CB1Z for evaluation/demonstration purposes. ...
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... AD7988-1/AD7988-5 NOTES ©2012 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D10231-0-2/12(A) Rev Page Data Sheet ...