EVAL-AD7687CB Analog Devices Inc, EVAL-AD7687CB Datasheet
EVAL-AD7687CB
Specifications of EVAL-AD7687CB
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EVAL-AD7687CB Summary of contents
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FEATURES 16-bit resolution with no missing codes Throughput: 250 kSPS INL: ±0.4 LSB typ, ±1.5 LSB max (±23 ppm of FSR) Dynamic range: 96.5 dB S/(N + D): 95 kHz THD: −118 kHz True ...
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... CS Mode 4-Wire with BUSY Indicator ................................... 21 Chain Mode, No BUSY Indicator ............................................ 22 Chain Mode with BUSY Indicator........................................... 23 Application Hints ........................................................................... 24 Layout .......................................................................................... 24 Evaluating the AD7687’s Performance.................................... 24 Outline Dimensions ....................................................................... 25 Ordering Guide .......................................................................... 26 Rev Page ...
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SPECIFICATIONS VDD = 2 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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AD7687 VDD = 2 5.5 V, VIO = 2 VDD, V Table 3. Parameter Conditions REFERENCE Voltage Range Load Current 250 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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AD7687 −40°C to +85°C, VDD = 2 4.5 V, VIO = 2 4 VDD + 0.3 V, whichever is the lowest, unless otherwise stated. See Figure 3 and Figure 4 for load conditions. Table ...
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ABSOLUTE MAXIMUM RATINGS Table 6. Parameter Rating Analog Inputs 1 1 IN+ , IN− GND − 0 VDD + 0 ±130 mA REF GND − 0 VDD + 0.3 V Supply Voltages VDD, VIO ...
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AD7687 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS REF 1 10 VDD 2 9 AD7687 IN TOP VIEW (Not to Scale) IN– GND 5 6 Figure 5. 10-Lead MSOP Pin Configuration Table 8. Pin Function Descriptions 1 Pin ...
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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 code ...
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AD7687 TYPICAL PERFORMANCE CHARACTERISTICS 1.5 POSITIVE INL = +0.32LSB NEGATIVE INL = –0.41LSB 1.0 0.5 0 –0.5 –1.0 –1.5 0 16384 32768 CODE Figure 7. Integral Nonlinearity vs. Code 300000 258680 250000 200000 150000 100000 50000 0 0 1049 0 ...
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S/[ 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 VREF = 5V, –10dB 95 VREF = 2.5V, –10dB 90 ...
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AD7687 100 –10 –8 –6 –4 INPUT LEVEL (dB) Figure 19. SNR vs. Input Level 1000 f = 100kSPS S 750 500 250 0 2.3 2.7 3.1 3.5 3.9 SUPPLY ...
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IN+ 32,768C REF GND 32,768C IN– CIRCUIT INFORMATION The AD7687 is a fast, low power, single-supply, precise 16-bit ADC using a successive approximation architecture. The AD7687 is capable of converting 250,000 samples per second (250 kSPS) and powers down between ...
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AD7687 Transfer Functions The ideal transfer characteristic for the AD7687 is shown in Figure 26 and Table 9. 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 ...
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ANALOG INPUT Figure 28 shows an equivalent circuit of the input structure of the AD7687. 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 ...
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AD7687 DRIVER AMPLIFIER CHOICE Although the AD7687 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 ...
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Figure 32, which represents PSRR over frequency. 100 95 VDD = VDD = 2. 100 ...
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AD7687 CS MODE 3-WIRE, NO BUSY INDICATOR This mode is usually used when a single AD7687 is connected to an SPI-compatible digital host. The connection diagram is shown in Figure 35 and the corresponding timing is given in Figure 36. ...
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CS MODE 3-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7687 is connected to an SPI-compatible digital host having an interrupt input. The connection diagram is shown in Figure 37 and the corresponding timing is given ...
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AD7687 CS MODE 4-WIRE, NO BUSY INDICATOR This mode is usually used when multiple AD7687s are connected to an SPI-compatible digital host. A connection diagram example using two AD7687s is shown in Figure 39 and the corresponding timing is given ...
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CS MODE 4-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7687 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 the ...
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AD7687 CHAIN MODE, NO BUSY INDICATOR This mode can be used to daisy chain multiple AD7687s wire serial interface. This feature is useful for reducing component count and wiring connections, for example, in isolated multiconverter applications or ...
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CHAIN MODE WITH BUSY INDICATOR This mode can also be used to daisy-chain multiple AD7687s 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 isolated ...
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... Figure 47 and Figure 48. EVALUATING THE AD7687’S PERFORMANCE Other recommended layouts for the AD7687 are outlined in the documentation of the evaluation board for the AD7687 (EVAL-AD7687). The evaluation board package includes a fully assembled and tested evaluation board, documentation, and software for controlling the board from a PC via the EVAL-CONTROL BRD3 ...
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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° 0.30 ...
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... Z = RoHS Compliant Part, # denotes RoHS compliant product, may be top or bottom marked. 2 The EVAL-AD7687CB can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL BRDx for evaluation/demonstration purposes. 3 The EVAL-CONTROL BRD2 and EVAL-CONTROL BRD3 allow control and communicate with all Analog Devices evaluation boards ending in the CB designators. ...
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NOTES Rev Page AD7687 ...
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AD7687 NOTES ©2005–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02972-0-2/11(A) Rev Page ...