AD7864AS Analog Devices, AD7864AS Datasheet
AD7864AS
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AD7864AS Summary of contents
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... CS and RD signals. Maximum through- put for a single channel is 500 kSPS. For all four channels the REV. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use ...
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AD7864–SPECIFICATIONS Parameter SAMPLE AND HOLD –3 dB Full Power Bandwidth Aperture Delay Aperture Jitter Aperture Delay Matching 2 DYNAMIC PERFORMANCE Signal to (Noise + Distortion) Ratio @ + MIN MAX 3 Total Harmonic Distortion 3 Peak ...
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Parameter LOGIC INPUTS Input High Voltage, V INH Input Low Voltage, V INL Input Current Input Capacitance LOGIC OUTPUTS Output High Voltage Output Low Voltage DB11–DB0 High Impedance Leakage Current 4 ...
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AD7864 TIMING CHARACTERISTICS Parameter A, B Versions t 1.65 CONV 13 2.6 t 0.34 ACQ t No. of Channels BUSY x (t CONV t —External V 2 WAKE-UP REF 3 t —Internal V 6 WAKE-UP REF ...
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... Ranges AD7864AS AD7864BS AD7864AS-3 2.5 V AD7864AS 2 *The A Version is fully specified up to +105 C with degraded INL and DNL specifications of 2 LSBs max. FRSTDATA CONVST CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection ...
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AD7864 Pin Mnemonic Description Busy Output. The busy output is triggered high by the rising edge of CONVST and remains high until 1 BUSY conversion is completed on all selected channels. 2 FRSTDATA First Data Output. FRSTDATA is a logic ...
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TERMINOLOGY Signal to (Noise + Distortion) Ratio This is the measured ratio of signal to (noise + distortion) at the output of the A/D converter. The signal is the rms amplitude of the fundamental. Noise is the rms sum of ...
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AD7864 CONVERTER DETAILS The AD7864 is a high speed, low power, 4-channel simulta- neous sampling 12-bit A/D converter that operates from a single +5 V supply. The part contains a 1.65 s successive approxima- tion ADC, four track/hold amplifiers, an ...
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AD7864-1 Figure 2 shows the analog input section of the AD7864-1. Each input can be configured for operation on the AD7864-1. For 5 V (AD7864-1) operation, the V V inputs are tied together and the ...
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AD7864 AD7864-3 Figure 4 shows the analog input section of the AD7864-3. The analog input range is 2 the V IN1A input can be left unconnected but connected to a poten- tial then that potential ...
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CONVST t BUSY 2 EOC FRSTDATA RD CS DATA H/S SEL SL1–SL4 Figure 7. Timing Diagram for Reading During Conversion TIMING AND CONTROL Reading Between Each Conversion in the Conversion Sequence Figure 7 shows the timing and control ...
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AD7864 t 1 CONVST t BUSY 2 EOC RD CS DATA FRSTDATA Figure 8. Timing Diagram, Reading After the Conversion Sequence Reading After the Conversion Sequence Figure 8 shows the same conversion sequence as Figure 7. In this case, however, ...
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CLK CONVST FRSTDATA EOC RD BUSY Standby Mode Operation The AD7864 has a Standby Mode whereby the device can be placed in a low current consumption mode (5 A typ). The AD7864 is placed in standby by bringing the logic ...
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AD7864 low. At this point the logic output FRSTDATA will go logic high to indicate that the output data register pointer is address- ing Register Number 1. When CS and RD are both logic low the contents of the addressed ...
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ADC CODE Figure 14. Histogram of 8192 Conversions Input The output spectrum from the ADC is ...
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AD7864 AC Linearity Plots The plots shown in Figure 18 below show typical DNL and INL plots for the AD7864. 3.00E–01 2.00E–01 1.00E–01 0.00E+00 –1.00E–01 –2.00E–01 –3.00E–01 0 500 1000 1500 2000 ADC CODE 2.50E–01 2.00E–01 1.50E–01 1.00E–01 5.00E–02 0.00E+00 ...
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MICROPROCESSOR INTERFACING The high speed parallel interface of the AD7864 allows easy interfacing to most DSP processors and microprocessors. The ADC7864 interface of the AD7864 consists of the data lines (DB0–DB11), CS, RD, WR, EOC and BUSY. AD7864–ADSP-2100/ADSP-2101/ADSP-2102 Interface Figure ...
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AD7864 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 independently. ...
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REV. A OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 44-Lead Plastic Quad Flatpack (S-44) 0.548 (13.925) 0.546 (13.875) 0.096 (2.44) 0.398 (10.11) MAX 0.390 (9.91) 0.037 (0.94) 8° 0.025 (0.64) 33 0.8° 34 SEATING PLANE TOP VIEW (PINS DOWN) ...