AD7721ARZ-REEL Analog Devices Inc, AD7721ARZ-REEL Datasheet
AD7721ARZ-REEL
Specifications of AD7721ARZ-REEL
Related parts for AD7721ARZ-REEL
AD7721ARZ-REEL Summary of contents
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FEATURES 16-Bit Sigma-Delta ADC 468.75 kHz Output Word Rate (OWR) No Missing Codes Low-Pass Digital Filter High Speed Serial Interface Linear Phase 229.2 kHz Input Bandwidth Power Supplies Standby Mode (70 ...
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AD7721–SPECIFICATIONS Parameter SERIAL MODE ONLY STATIC PERFORMANCE Resolution Minimum Resolution for Which No Missing Codes Is Guaranteed Differential Nonlinearity Integral Nonlinearity DC CMRR 2 Offset Error Unipolar Mode Bipolar Mode 2, 3 Full-Scale Error Unipolar Mode Bipolar Mode Unipolar Offset ...
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SPECIFICATIONS REFIN = +2 Parameter PARALLEL MODE ONLY STATIC PERFORMANCE Resolution Minimum Resolution for Which No Missing Codes Is Guaranteed Differential Nonlinearity Integral Nonlinearity DC CMRR 2 Offset Error Unipolar Mode Bipolar Mode 2, 3 Full-Scale ...
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AD7721 TIMING CHARACTERISTICS Limit at T Parameter (A, S Versions) Serial Interface 3 f 100 CLK 15 t 0.45 t CLK LO CLK t 0.45 t CLK HI CLK CLK – CLK ...
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ABSOLUTE MAXIMUM RATINGS (T = +25 C unless otherwise stated DGND . . . . . . . . . . . . . . . . . . . . . . . –0.3 V ...
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AD7721 Mnemonic Function AV Analog Positive Supply Voltage AGND Ground reference point for analog circuitry. DV Digital Supply Voltage DGND Ground reference point for digital circuitry. DGND must be connected via its own short ...
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Parallel Mode Only Mnemonic Function CS Chip Select Logic Input. RD Read Logic Input. This digital input is used in conjunction with CS to read data from the device. WR Write Logic Input. This digital input is used in conjunction ...
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AD7721 TERMINOLOGY Integral Nonlinearity This is the maximum deviation of any code from a straight line passing through the endpoints of the transfer function. The end- points of the transfer function are zero scale (not to be con- fused with ...
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Input Circuits The purpose of antialiasing filters is to attenuate out of band signals that would otherwise be mixed down into the signal band. With traditional ADCs, high order filters using expensive high tolerance passive components are often required to ...
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AD7721 switching the positive input of the modulator to the reference voltage and the negative input to AGND. Again, when the modulator and digital filter settle, a gain correction factor is calculated from the average of 8 output results and ...
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CIRCUIT DESCRIPTION Sigma-Delta ADC The AD7721 ADC employs a sigma-delta conversion technique that converts the analog input into a digital pulse train. Due to the high oversampling rate, which spreads the quantiza- tion noise from /2, the ...
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AD7721 PARALLEL INTERFACE Read Operation The device defaults to parallel mode if CS, RD and WR are not tied to DGND together. Figure 11 shows a timing diagram for reading from the AD7721 in the parallel mode. When operating the ...
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MICROCOMPUTER/MICROPROCESSOR INTERFACING The AD7721 has a variety of interfacing options. It offers two operating modes—serial and parallel. Serial Interfacing In serial mode, the AD7721 can be directly interfaced to several DSPs. In all cases, the AD7721 operates as the master ...
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AD7721 Parallel Interface In parallel mode, the DRDY signal is still available. This signal can be used to generate an interrupt in the DSP as DRDY goes high for two clock cycles when a conversion is complete. Data is available ...
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A15–A0 EN ADDR IS DECODE CS IRQ STRB RD/W 1Y1 1G 2G 1A1 1Y2 1A2 1Y3 1A3 1Y4 1A4 HC244 2A1 2Y1 2Y2 2A2 2Y3 2A3 2Y4 2A4 D11– 1A1 1Y1 1Y2 1A2 TMS320C20/ 1Y3 1A3 1Y4 1A4 ...
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AD7721 0.250 (6.35) MAX 0.200 (5.05) 0.125 (3.18) 0.0118 (0.30) 0.0040 (0.10) 0.005 (0.13) MIN 0.225 (5.72) MAX 0.200 (5.08) 0.125 (3.18) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). Plastic DIP (N-28) 1.565 (39.70) 1.380 (35.10 0.580 ...