AD7685BCPZRL7 Analog Devices Inc, AD7685BCPZRL7 Datasheet
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AD7685BCPZRL7
Specifications of AD7685BCPZRL7
AD7685BCPZRL7TR
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AD7685BCPZRL7 Summary of contents
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FEATURES 16-bit resolution with no missing codes Throughput: 250 kSPS INL: ±0.6 LSB typical, ±2 LSB maximum (±0.003% of FSR) SINAD: 93 kHz THD: −110 kHz Pseudo differential analog input range ...
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AD7685 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Application Diagram........................................................................ 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications....................................................................... 5 Absolute Maximum Ratings............................................................ 7 ESD Caution.................................................................................. 7 Pin Configuration and Function Descriptions............................. 8 Terminology ...................................................................................... ...
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SPECIFICATIONS VDD = 2 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 = 250 kHz IN ...
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AD7685 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, VIO = 2 5 VDD + 0.3 V, whichever is the lowest, unless otherwise stated. 1 Table 4. VDD = 4 5.5 V Parameter Conversion Time: CNV Rising Edge ...
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AD7685 −40°C to +85°C, VIO = 2 4 VDD + 0.3 V, whichever is the lowest, unless otherwise stated. 1 Table 5. VDD = 2.3V to 4.5 V Parameter Conversion Time: CNV Rising Edge to Data ...
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ABSOLUTE MAXIMUM RATINGS Table 6. Parameter Rating Analog Inputs 1 1 IN+ , IN− , REF GND − 0 VDD + 0 ±130 mA Supply Voltages VDD, VIO to GND −0 VDD ...
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AD7685 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS REF 1 10 VDD 2 9 AD7685 IN TOP VIEW (Not to Scale) IN– GND 5 6 Figure 5. 10-Lead MSOP Pin Configuration Table 7. Pin Function Descriptions 1 Pin ...
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TERMINOLOGY Integral Nonlinearity Error (INL) INL 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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AD7685 TYPICAL PERFORMANCE CHARACTERISTICS 2.0 POSITIVE INL = +0.33LSB NEGATIVE INL = –0.50LSB 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 204292 200000 150000 100000 50000 29041 27755 0 ...
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REFERENCE VOLTAGE (V) Figure 13. SNR, SINAD, and ENOB vs. Reference Voltage 100 5V, –10dB REF 5V, –1dB REF ...
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AD7685 95 94 SNR 93 92 THD 91 90 –10 –8 –6 –4 INPUT LEVEL (dB) Figure 19. SNR and THD vs. Input Level 1000 750 VDD 500 250 VIO 0 2.3 2.7 3.1 3.5 3.9 4.3 SUPPLY (V) Figure ...
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THEORY OF OPERATION IN+ REF GND IN– CIRCUIT INFORMATION The AD7685 is a fast, low power, single-supply, precise 16-bit ADC using a successive approximation architecture. The AD7685 is capable of converting 250,000 samples per second (250 kSPS) and powers down ...
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AD7685 Transfer Functions The ideal transfer characteristic for the AD7685 is shown in Figure 26 and Table 8. 111...111 111...110 111...101 000...010 000...001 000...000 –FS – LSB –FS + 0.5 LSB ANALOG INPUT Figure 26. ADC Ideal Transfer ...
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ANALOG INPUTS Figure 28 shows an equivalent circuit of the input structure of the AD7685. 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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AD7685 DRIVER AMPLIFIER CHOICE Although the AD7685 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 to preserve the SNR ...
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The AD7685 powers down automatically at the end of each conversion phase and, therefore, the power scales linearly with the sampling rate, as shown in Figure 32. This makes the part ideal for low sampling rate (even a few Hz) ...
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AD7685 CS MODE 3-WIRE, NO BUSY INDICATOR This mode is usually used when a single AD7685 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. ...
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CS MODE 3-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7685 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 given ...
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AD7685 CS MODE 4-WIRE, NO BUSY INDICATOR This mode is usually used when multiple AD7685s are connected to an SPI-compatible digital host. A connection diagram example using two AD7685s is shown in Figure 38, 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 AD7685 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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AD7685 CHAIN MODE, NO BUSY INDICATOR This mode can be used to daisy-chain multiple AD7685s 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 ...
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CHAIN MODE WITH BUSY INDICATOR This mode can also be used to daisy chain multiple AD7685s 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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AD7685 APPLICATION HINTS LAYOUT The printed circuit board (PCB) that houses the AD7685 should be designed so that the analog and digital sections are separated and confined to certain areas of the board. The pinout of the AD7685 with all ...
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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 48, using the AD7685 and the ADuM1402C digital isolator, provides a ...
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AD7685 OUTLINE DIMENSIONS INDEX ARE A 1.50 BSC SQ 0.80 0.75 0.70 SEATING PLANE 3.10 3.00 2. 5.15 3.10 4.90 3.00 4.65 2. PIN 1 0.50 BSC 0.95 0.85 1.10 MAX 0.75 0.15 0.33 SEATING 0.23 ...
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... AD7685ARM ±6 LSB max AD7685ARMRL7 ±6 LSB max 1 AD7685ARMZ ±6 LSB max 1 AD7685ARMZRL7 ±6 LSB max 1 AD7685BCPZRL ±3 LSB max 1 AD7685BCPZRL7 ±3 LSB max AD7685BRM ±3 LSB max AD7685BRMRL7 ±3 LSB max AD7685BRMZ 1 ±3 LSB max 1 AD7685BRMZRL7 ±3 LSB max 1 AD7685CCPZRL ± ...
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AD7685 NOTES ©2004–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02968-0-3/07(B) Rev Page ...