ad7868bq Analog Devices, Inc., ad7868bq Datasheet
ad7868bq
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ad7868bq Summary of contents
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... The AD7868 is available in a 24-pin DIP and a 28-pin SOIC package. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 617/329-4700 2 LC MOS AD7868 DAC OUT 12-BIT DAC DAC 3V RO DAC REFERENCE ADC 3V REFERENCE RO ADC R R 12-BIT V IN ADC TRACK/HOLD V AGND SS © Analog Devices, Inc., 1996 Fax: 617/326-8703 ...
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AD7868–SPECIFICATIONS ( 5 ADC SECTION unless otherwise noted.) Parameter 2 DYNAMIC PERFORMANCE 3, 4 Signal-to-Noise Ratio (SNR MIN MAX Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise Intermodulation ...
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... As per ADC Section Model AD7868AN AD7868AQ AD7868BN AD7868BQ AD7868AR AD7868BR *N = Plastic DIP Cerdip SOIC (Small Outline IC). –3– AD7868 unless otherwise noted.) MAX Test Conditions/Comments kHz Sine Wave kHz OUT SAMPLE Typically 71 +25 C for 0 < ...
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AD7868 TIMING CHARACTERISTICS Limit at T MIN Parameter (A, B Versions) ADC TIMING 440 2 t 100 100 4 t 155 100 RCLK +200 ...
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PIN FUNCTION DESCRIPTION DIP Pin Number Mnemonic Function POWER SUPPLY 7 & Positive Power Supply & Negative Power Supply, – & 19 AGND Analog Ground. Both AGND pins must ...
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AD7868 CONVERTER DETAILS The AD7868 is a complete 12-bit I/O port, the only external components required for normal operation are pull-up resistors for the ADC data outputs and power supply decoupling capaci- tors comprised of a 12-bit successive ...
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REF OUT 100 50 DAC OUTPUT WITH ALL 0s LOADED REF OUT DECOUPLED AS SHOWN IN 20 FIGURE 100 200 1k 2k FREQUENCY – Hz Figure 3. Noise Spectral Density vs. Frequency INPUT/OUTPUT TRANSFER FUNCTIONS ...
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AD7868 TIMING AND CONTROL Communication with the AD7868 is managed by 6 dedicated pins. These consist of separate serial clocks, word framing or strobe pulses and data signals for both receiving and transmit- ting data. Conversion starts and DAC updating ...
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... SNR data can be ob- tained. Figure 9 shows a typical 2048 point FFT plot of the AD7868BQ ADC with an input signal of 10 kHz and a sam- pling frequency of 83 kHz. The SNR obtained from this graph is 73 dB. It should be noted that the harmonics are taken into account when calculating the SNR ...
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AD7868 LOW-PASS MICRO- AD7868 DAC CONTROLLER FILTER Figure 11. AD7868 DAC Dynamic Performance Test Circuit The digitizer sampling is synchronized with the DAC update rate to ease FFT calculations. The digitizer samples the DAC output after the output has settled ...
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MICROPROCESSOR INTERFACING Microprocessor interfacing to the AD7868 is via a serial bus that uses standard protocol compatible with DSP machines. The communication interface consists of separate transmit (DAC) and receive (ADC) sections whose operations can be either syn- chronous or ...
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AD7868 AD7868—TMS32020/TMS320C25 Interface Figure 18 shows an interface which is suitable for the TMS32020/TMS320C25 processors. This interface is config- ured for synchronous, continuous clock operation. Note, the AD7868 will not interface correctly to these processors if the AD7868 is configured ...
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ANALOG INPUT LK1 3V RANGE A B SKT1 C COMPONENT GRID COMPONENT GRID LK2 C SKT2 B A ANALOG OUTPUT 3V RANGE V + C10 C9 0 ADG201HS AD711 + IC3 V– C12 C11 ...
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AD7868 LK4, DAC Reference Selection The DAC reference may be connected to either the ADC refer- ence output (RO ADC the DAC reference (RO DAC). LK5, ADC Internal Clock Selection This link configures the ADC for continuous or ...
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Figure 22. Component Side Layout for the Circuit Diagram of Figure 19 Figure 23. Solder Side Layout for the Circuit Diagram of Figure 19 REV. B –15– AD7868 ...
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AD7868 24-Pin Plastic (N-24) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 28-Pin Plastic SOIC (R-28) –16– 24-Pin Cerdip (Q-24) REV. B ...