AD7688BRMZ Analog Devices Inc, AD7688BRMZ Datasheet
AD7688BRMZ
Specifications of AD7688BRMZ
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AD7688BRMZ Summary of contents
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FEATURES 16-bit resolution with no missing codes Throughput: 500 kSPS INL: ±0.4 LSB typ, ±1.5 LSB max (±23 ppm of FSR) Dynamic range: 96.5 dB SNR: 95 kHz THD: −118 kHz True differential analog ...
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AD7688 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Application Diagram........................................................................ 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications....................................................................... 5 Absolute Maximum Ratings............................................................ 6 Thermal Resistance ...................................................................... 6 ESD Caution.................................................................................. 6 Pin Configuration and Function ...
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SPECIFICATIONS VDD = 4 5.5 V, VIO = 2 VDD, V Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Absolute Input Voltage Common-Mode Input Range Analog Input CMRR Leakage Current at 25°C Input Impedance ACCURACY No ...
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AD7688 VDD = 4 5.5 V, VIO = 2 VDD, V Table 3. Parameter Conditions REFERENCE Voltage Range Load Current 500 kSPS, REF = 5 V SAMPLING DYNAMICS −3 dB Input Bandwidth Aperture Delay VDD = ...
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TIMING SPECIFICATIONS −40°C to +85°C, VDD = 4 5.5 V, VIO = 2 5 VDD + 0.3 V, whichever is the lowest, unless otherwise stated. See Figure 3 and Figure 4 for load conditions. ...
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AD7688 ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Rating Analog Inputs 1 1 IN+ , IN− GND − 0 VDD + 0 ±130 mA REF GND − 0 VDD + 0.3 V Supply Voltages VDD, ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS REF 1 10 VDD 2 9 AD7688 IN TOP VIEW (Not to Scale) IN– GND 5 6 Figure 5. 10-Lead MSOP Pin Configuration Table 7. Pin Function Descriptions Pin No. Mnemonic ...
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AD7688 TERMINOLOGY Integral Nonlinearity Error (INL) It refers to the deviation of each individual code from a line drawn from negative full scale through positive full scale. The point used as negative full scale occurs ½ LSB before the first ...
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TYPICAL PERFORMANCE CHARACTERISTICS 1.5 POSITIVE INL = +0.31LSB NEGATIVE INL = –0.39LSB 1.0 0.5 0 –0.5 –1.0 –1.5 0 16384 32768 CODE Figure 7. Integral Nonlinearity vs. Code 300000 256159 250000 200000 150000 100000 50000 0 0 2930 0 6F ...
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AD7688 100 95 ENOB 2.3 2.7 3.1 3.5 3.9 4.3 REFERENCE VOLTAGE (V) Figure 13. SNR, S/(N + D), and ENOB vs. Reference Voltage 100 –55 –35 – TEMPERATURE (°C) ...
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VDD 750 500 250 VIO 0 4.50 4.75 5.00 SUPPLY (V) Figure 19. Operating Currents vs. Supply 1000 750 500 250 0 –55 –35 – TEMPERATURE (°C) Figure 20. Power-Down Currents vs. Temperature 1000 VDD ...
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AD7688 IN+ 32,768C REF GND 32,768C IN– CIRCUIT INFORMATION The AD7688 is a fast, low power, single-supply, precise 16-bit ADC using a successive approximation architecture. The AD7688 is capable of converting 500,000 samples per second (500 kSPS) and powers down ...
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Transfer Functions The ideal transfer characteristic for the AD7688 is shown in Figure 25 and Table 8. 011...111 011...110 011...101 100...010 100...001 100...000 –FSR –FSR + 1 LSB –FSR + 0.5 LSB +FSR – 1.5 LSB ANALOG INPUT Figure 25. ...
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AD7688 ANALOG INPUT Figure 27 shows an equivalent circuit of the input structure of the AD7688. The two diodes, D1 and D2, provide ESD protection for the analog inputs IN+ and IN−. Care must be taken to ensure that the ...
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DRIVER AMPLIFIER CHOICE Although the AD7688 is easy to drive, the driver amplifier needs to meet the following requirements: • The noise generated by the driver amplifier needs to be kept as low as possible in order to preserve the ...
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AD7688 100 FREQUENCY (kHz) Figure 31. PSRR vs. Frequency The AD7688 powers down automatically at the end of each conversion phase and, therefore, the power scales linearly with the sampling ...
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CS MODE 3-WIRE, NO BUSY INDICATOR This mode is usually used when a single AD7688 is connected to an SPI-compatible digital host. The connection diagram is shown in Figure 34 and the corresponding timing is given in Figure 35. With ...
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AD7688 CS MODE 3-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7688 is connected to an SPI-compatible digital host having an interrupt input. The connection diagram is shown in Figure 36 and the corresponding timing is ...
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CS MODE 4-WIRE, NO BUSY INDICATOR This mode is usually used when multiple AD7688s are connected to an SPI-compatible digital host. A connection diagram example using two AD7688s is shown in Figure 38 and the corresponding timing is given in ...
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AD7688 CS MODE 4-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7688 is connected to an SPI-compatible digital host, which has an interrupt input, and it is desired to keep CNV, which is used to sample ...
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CHAIN MODE, NO BUSY INDICATOR This mode can be used to daisy-chain multiple AD7688s wire serial interface. This feature is useful for reducing component count and wiring connections, for example, in isolated multiconverter applications or for systems ...
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AD7688 CHAIN MODE WITH BUSY INDICATOR This mode can also be used to daisy-chain multiple AD7688s on a 3-wire serial interface while providing a BUSY indicator. This feature is useful for reducing component count and wiring connections, for example, in ...
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APPLICATION HINTS LAYOUT The printed circuit board that houses the AD7688 should be designed so that the analog and digital sections are separated and confined to certain areas of the board. The pinout of the AD7688, with all its analog ...
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AD7688 OUTLINE DIMENSIONS IDENTIFIER PIN 1 INDEX AREA 0.80 0.75 0.70 SEATING PLANE 3.10 3.00 2.90 5. 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° ...
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... ORDERING GUIDE Integral Model Nonlinearity AD7688BRMZ ±1.5 LSB max AD7688BRMZRL7 ±1.5 LSB max AD7688BCPZRL ±1.5 LSB max AD7688BCPZRL7 ±1.5 LSB max EVAL-AD7688CBZ EVAL-CONTROL BRD2Z EVAL-CONTROL BRD3Z RoHS Compliant Part, # denotes RoHS compliant product, may be top or bottom marked. 2 The EVAL-AD7688CB can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL BRDx for evaluation/demonstration purposes. ...
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AD7688 NOTES Rev Page ...
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NOTES Rev Page AD7688 ...
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AD7688 NOTES ©2007–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02973-0-2/11(A) Rev Page ...