AD670BD AD [Analog Devices], AD670BD Datasheet
AD670BD
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AD670BD Summary of contents
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FEATURES Complete 8-Bit Signal Conditioning A/D Converter Including Instrumentation Amp and Reference Microprocessor Bus Interface 10 s Conversion Speed Flexible Input Stage: Instrumentation Amp Front End Provides Differential Inputs and High Common-Mode Rejection No User Trims Required No Missing ...
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AD670–SPECIFICATIONS Model OPERATING TEMPERATURE RANGE RESOLUTION CONVERSION TIME RELATIVE ACCURACY MIN MAX 1 DIFFERENTIAL LINEARITY ERROR MIN MAX GAIN ACCURACY @ + MIN MAX UNIPOLAR ZERO ERROR @ +25 C ...
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Model Min OPERATING TEMPERATURE RANGE –40 RESOLUTION CONVERSION TIME RELATIVE ACCURACY MIN MAX 1 DIFFERENTIAL LINEARITY ERROR MIN MAX GAIN ACCURACY @ + MIN MAX UNIPOLAR ZERO ERROR @ +25 ...
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... C to +70 C AD670JP +70 C AD670KN +70 C AD670KP +70 C AD670AD – +85 C AD670BD – +85 C AD670SD – +125 C NOTES 1 For details on grade and package offerings screened in accordance with MIL-STD-883 refer to the Analog Devices Military Products Databook Ceramic DIP ...
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CONNECTING THE AD670 The AD670 has been designed for ease of use. All active com- ponents required to perform a complete A/D conversion are on board and are connected internally. In addition, all calibration trims are performed at the factory, ...
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AD670 Figure 4a. CMRR Over Frequency Figure 4b. AD670 Input Rejects Common-Mode Ground Noise Good common-mode performance is useful in a number of situ- ations. In bridge-type transducer applications, such performance facilitates the recovery of differential analog signals in the ...
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Bipolar 6c. Full Scale (Unipolar) Figure 6. Transfer Curves CONTROL AND TIMING OF THE AD670 Control Logic The AD670 contains on-chip logic to provide conversion and data read operations from signals commonly available in micro- processor systems. Figure 7 ...
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AD670 Figure 8. Write/Convert Start Timing The R/W line is used to direct the converter to start a conver- sion (R/W low) or read data (R/W high). The relative sequenc- ing of the three control signals (R/W, CE, CS) is ...
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APPLYING THE AD670 The AD670 has been designed for ease of use, system compat- ibility, and minimization of external components. Transducer interfaces generally require signal conditioning and preampli- fication before the signal can be converted. The AD670 will reduce and ...
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AD670 STRAIN GAGE MEASUREMENTS Many semiconductor-type strain gages, pressure transducers, and load cells may also be connected directly to the AD670. These types of transducers typically produce 30 mV full-scale per volt of excitation. In the circuit shown in Figure ...
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Figure 17. Low Cost Sample-and-Hold Circuit for AD670 Since settling to 1/2 LSB at 8-bits of resolution requires 6.2 RC time constants, the 500 pF hold capacitors and CD4066’s 300 on-resistance yield an acquisition time of under 1 s, assuming ...
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AD670 20-Pin Plastic DIP (N-20) 0.048 (1.21) 0.042 (1.07) 0.048 (1.21) 0.042 (1.07) 0.020 (0.50) R OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 20-Terminal PLCC Package(P-20A) 0.180 (4.57) 0.165 (4.19) 0.056 (1.42) 0.025 (0.63) 0.042 (1.07) 0.015 (0.38) 3 ...