AD7874ARZ Analog Devices Inc, AD7874ARZ Datasheet
AD7874ARZ
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AD7874ARZ Summary of contents
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FEATURES Four On-Chip Track/Hold Amplifiers Simultaneous Sampling of 4 Channels Fast 12-Bit ADC with 8 s Conversion Time/Channel 29 kHz Sample Rate for All Four Channels On-Chip Reference 10 V Input Range 5 V Supplies APPLICATIONS Sonar Motor Controllers ...
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AD7874–SPECIFICATIONS Parameter A Version B Version S Version Units SAMPLE-AND-HOLD 2 Acquisition Time to 0.01 Droop Rate 1 3 –3 dB Small Signal Bandwidth 500 2 Aperture Delay Aperture Jitter 200 2 Aperture ...
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TIMING CHARACTERISTICS Parameter A, B Versions 130 CONV 32 ...
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AD7874 TERMINOLOGY ACQUISITION TIME Acquisition Time is the time required for the output of the track/hold amplifiers to reach their final values, within 1/2 LSB, after the falling edge of INT (the point at which the track/ holds return to ...
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PIN FUNCTION DESCRIPTION Pin Mnemonic 1 V IN1 2 V IN2 INT 5 CONVST CLK DB11 11–13 DB10–DB8 14 DGND 15–21 DB7–DB1 22 DB0 23 AGND 24 ...
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AD7874 CONVERTER DETAILS The AD7874 is a complete 12-bit, 4-channel data acquisition system comprised of a 12-bit successive approximation ADC, four high speed track/hold circuits, a four-channel analog multiplexer and Zener reference. The ADC uses ...
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OUTPUT CODE 011...111 011...110 000...010 – 000...001 FS 2 000...000 111...111 111...110 100...001 100...000 0V INPUT VOLTAGE Figure 5. Input/Output Transfer Function OFFSET AND FULL-SCALE ADJUSTMENT In most Digital Signal Processing (DSP) applications, offset and full-scale errors have little or ...
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AD7874 The first read operation to the AD7874 after conversion always accesses data from Data Register 1 (i.e., the conversion result from the V input). INT is reset high on the falling edge of IN1 RD during this first read ...
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Total Harmonic Distortion (THD) Total Harmonic Distortion (THD) is the ratio of the rms sum of harmonics to the rms value of the fundamental. For the AD7874, THD is defined THD 20 ...
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AD7874 MICROPROCESSOR INTERFACING The AD7874 high speed bus timing allows direct interfacing to DSP processors as well as modern 16-bit microprocessors. Suitable microprocessor interfaces are shown in Figures 12 through 16. AD7874–ADSP-2100 Interface Figure 12 shows an interface between the ...
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Some applications may require that the conversion is initiated by the microprocessor rather than an external timer. One option is to decode the AD7874 CONVST from the address bus so that a write operation starts a conversion. Data is read ...
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AD7874 APPLICATIONS Vector Motor Control The current drawn by a motor can be split into two compo- nents: one produces torque and the other produces magnetic flux. For optimal performance of the motor, these two compo- nents should be controlled ...
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MULTIPLE AD7874s Figure 18 shows a system where a number of AD7874s can be configured to handle multiple input channels. This type of con- figuration is common in applications such as sonar, radar, etc. The AD7874 is specified with maximum ...
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AD7874 LK1 SKT1 LK2 SKT2 LK3 SKT3 LK4 SKT4 V– Figure 20. Data Acquisition Circuit Using the AD7874 IC3 CONVST 78L05 SKT6 IC1 V AD713 CONVST IN1 ...
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Figure 22. PCB Component Side Layout for the Circuit of Figure 20 Figure 23. PCB Solder Side Layout for the Circuit of Figure 20 REV. C –15– AD7874 ...
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AD7874 SHORTING PLUG OPTIONS There are seven shorting plug options which must be set before using the board. These are outlined below: LK1–LK4 Connects the analog inputs to the buffer amplifi- ers. The analog inputs may also be connected to ...