AD7686BRMZ Analog Devices Inc, AD7686BRMZ Datasheet
AD7686BRMZ
Specifications of AD7686BRMZ
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AD7686BRMZ Summary of contents
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FEATURES 16-bit resolution with no missing codes Throughput: 500 kSPS INL: ±0.6 LSB typ, ±2 LSB max (±0.003% of FSR) S/(N + D): 92 kHz THD: −110 kHz Pseudo-differential analog input range 0 V ...
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AD7686 TABLE OF CONTENTS Specifications..................................................................................... 3 Timing Specifications....................................................................... 5 Absolute Maximum Ratings............................................................ 6 ESD Caution.................................................................................. 6 Pin Configuration and Function Descriptions............................. 7 Terminology ...................................................................................... 8 Typical Performance Characteristics ............................................. 9 Circuit Information.................................................................... 12 Converter Operation.................................................................. 12 Typical Connection Diagram ................................................... ...
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SPECIFICATIONS VDD = 4 5.5 V, VIO = 2 VDD, V Table 2. Parameter Conditions RESOLUTION ANALOG INPUT Voltage Range IN+ − IN− Absolute Input Voltage IN+ IN− Analog Input CMRR f = 200 kHz IN ...
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AD7686 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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AD7686 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 CONFIGURATIONS AND FUNCTION DESCRIPTIONS REF 1 10 VDD 2 9 AD7686 IN TOP VIEW (Not to Scale) IN– GND 5 6 Figure 5. 10-Lead MSOP Pin Configuration Table 6. Pin Function Descriptions Pin No. Mnemonic ...
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AD7686 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 2.0 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 0 16384 32768 CODE Figure 7. Integral Nonlinearity vs. Code 250000 202719 200000 150000 100000 50000 27583 8026 8027 8028 8029 802A CODE IN ...
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AD7686 100 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) Figure ...
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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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AD7686 IN+ 32,768C REF GND 32,768C IN– CIRCUIT INFORMATION The AD7686 is a fast, low power, single-supply, precise 16-bit ADC using a successive approximation architecture. The AD7686 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 AD7686 is shown in Figure 25 and Table 7. 111...111 111...110 111...101 000...010 000...001 000...000 –FSR –FSR + 1 LSB –FSR + 0.5 LSB +FSR – 1.5 LSB ANALOG INPUT Figure 25. ...
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AD7686 ANALOG INPUT Figure 27 shows an equivalent circuit of the input structure of the AD7686. 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 AD7686 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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AD7686 The AD7686 powers down automatically at the end of each conversion phase and, therefore, the power scales linearly with the sampling rate, as shown in Figure 31. This makes the part ideal for low sampling rate (even a few ...
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CS MODE 3-WIRE, NO BUSY INDICATOR This mode is usually used when a single AD7686 is connected to an SPI-compatible digital host. The connection diagram is shown in Figure 33 and the corresponding timing is given in Figure 34. With ...
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AD7686 CS MODE 3-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7686 is connected to an SPI-compatible digital host having an interrupt input. The connection diagram is shown in Figure 35 and the corresponding timing is ...
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CS MODE 4-WIRE, NO BUSY INDICATOR This mode is usually used when multiple AD7686s are connected to an SPI-compatible digital host. A connection diagram example using two AD7686s is shown in Figure 37 and the corresponding timing is given in ...
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AD7686 CS MODE 4-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7686 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 AD7686s on a 3-wire serial interface. This feature is useful for reducing component count and wiring connections, for example, in isolated multiconverter applications or for systems with ...
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AD7686 CHAIN MODE WITH BUSY INDICATOR This mode can also be used to daisy-chain multiple AD7686s on a 3-wire serial interface while providing a BUSY indicator. This feature is useful for reducing component count and wiring connections, for exmpale, in ...
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APPLICATION HINTS LAYOUT The printed circuit board that houses the AD7686 should be designed so that the analog and digital sections are separated and confined to certain areas of the board. The pinout of the AD7686, with all its analog ...
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AD7686 TRUE 16-BIT ISOLATED APPLICATION EXAMPLE In applications where high accuracy and isolation are required, for example, power monitoring, motor control, and some medical equipment, the circuit given in Figure 47, using the AD7686 and the ADuM1402C digital isolator, provides ...
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OUTLINE DIMENSIONS 3.00 BSC 3.00 BSC PIN 1 0.95 0.85 0.75 0.15 0.00 INDEX AREA 1.50 BCS SQ 0.80 0.75 0.70 SEATING PLANE 1 QFN package in development. Contact sales for samples and availability 4.90 BSC 1 5 ...
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AD7686 ORDERING GUIDE Integral Nonlinearity Model AD7686BRM ±3 LSB max AD7686BRMRL7 ±3 LSB max AD7686CRM ±2 LSB max AD7686CRMRL7 ±2 LSB max 1 EVAL-AD7686CB 2 EVAL-CONTROL BRD2 2 EVAL-CONTROL BRD3 1 This board can be used as a standalone evaluation ...
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NOTES Rev 0 | Page AD7686 ...
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AD7686 NOTES ©2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02969–0–4/05(0) Rev 0 | Page ...