AD779 Analog Devices, AD779 Datasheet
AD779
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AD779 Summary of contents
Page 1
... The converter utilizes a recursive subranging algorithm which includes error correction and flash converter circuitry to achieve high speed and resolution. The AD779 operates from +5 V and 12 V supplies and dissipates 560 mW (typ). Twenty-eight-pin plastic DIP and ceramic DIP packages are available. ...
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... Test Conditions –2– 10 128 kSPS, DD SAMPLE AD779K/B/T Max Min Typ Max –84 –90 –84 0.006 0.003 0.006 –82 –88 –82 0.008 0.004 0.008 –84 –90 –84 1 500 – ...
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... AD779 Units Bits LSB Bits % FSR* % FSR % FSR % FSR % FSR % FSR % FSR % FSR % FSR % FSR % FSR % FSR % FSR % FSR % FSR LSB LSB LSB mA mA ...
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... AD779 TIMING SPECIFICATIONS (All device types +12 V MIN MAX CC 5 10%) DD Parameter Symbol Min 1 Conversion Rate t CR Convert Pulse Width t 0.097 CP Aperture Delay Conversion Time t C Status Delay Access Time Float Delay t 10 ...
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... The AD779 features input protection circuitry consisting of large “distributed” diodes and polysilicon series resistors to dissipate both high energy discharges (Human Body Model) and fast, low energy pulses (Charged Device Model). Per Method 3015.2 of MIL-STD-883C, the AD779 has been classified as a Category 1 device. ...
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... AD779 28-Pin DIP Symbol Pin No. AGND 7 AIN 6 BIPOFF DGND 14 DB13–DB0 28–15 EOC 2 EOCEN REF 9 IN REF 8 OUT Type Analog Input Analog Output Digital Input Digital Output. All DO pins are three-state drivers Power. PIN DESCRIPTION ...
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... At this point, the amplitude of the reconstructed fundamental has degraded by less than –0.1 dB. Beyond this frequency, distortion of the sampled input signal increases significantly. The AD779 has been designed to optimize input bandwidth, allowing it to undersample input signals with frequencies significantly above the converter’s Nyquist frequency. ...
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... V 9.99939 V Application Information INPUT CONNECTIONS AND CALIBRATION The high ( input impedance of the AD779 eases the task of interfacing to high source impedances or multiplexer channel-to-channel mismatches 300 . The 10 V p-p full-scale input range accepts the majority of signal voltages without the need for voltage divider networks which could deteriorate the accuracy of the ADC ...
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... Figure 5. Bipolar Input Connections with Gain and Offset Trims Either or both of the trim pots can be replaced with 50 fixed resistors if the AD779 accuracy limits are sufficient for the application. If the pins are shorted together, the additional offset and gain errors will be approximately 80 LSB. ...
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... AD588 reference. The AD588 output is accurate to 0.65 mV from its value over the range. This results in a 0.06% FSR total gain drift for the AD779, which is a sub- stantial improvement over the on-chip reference performance of 0.11% FSR. A noise-reduction network on Pins 4, 6 and 7 has been shown ...
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... Figure 10. AD779 to 80186 DMA Interface AD779 TO Z80 The AD779 can be interfaced to the Z80 processor in an I/O or memory mapped configuration. Figure 11 illustrates an I/O con- figuration, where the AD779 occupies several port addresses to allow separate polling of the EOC status and reading of the data. ...
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... AD779 Figure 15. S/(N+D) vs. Input Frequency and Amplitude Figure 17. Nonaveraged IMD Plot for f 9.58 kHz ( 128 kSPS b 28-Lead Plastic DIP Package (N-28) Figure 16. 5-Plot Averaged 2048-Point FFT at 128 kSPS 10.009 kHz lN Figure 18. Power Supply Rejection (f = 9.08 kHz ( 128 kSPS, V SAMPLE OUTLINE DIMENSIONS Dimensions shown in inches and (mm) ...