EVAL-AD7862CB Analog Devices Inc, EVAL-AD7862CB Datasheet
EVAL-AD7862CB
Specifications of EVAL-AD7862CB
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EVAL-AD7862CB Summary of contents
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FEATURES Two Fast 12-Bit ADCs Four Input Channels Simultaneous Sampling & Conversion 4 s Throughput Time Single Supply Operation Selection of Input Ranges for AD7862-10 2.5 V for AD7862 2.5 V for AD7862-2 High ...
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AD7862–SPECIFICATIONS Parameter SAMPLE AND HOLD –3 dB Small Signal Bandwidth Aperture Delay Aperture Jitter Aperture Delay Matching 2 DYNAMIC PERFORMANCE 3 Signal to (Noise+Distortion) Ratio @ + MIN MAX 3 Total Harmonic Distortion 3 Peak Harmonic ...
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Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage DB11–DB0 Floating-State Leakage Current 4 Floating-State Capacitance Output Coding AD7862-10, AD7862-3 AD7863-2 CONVERSION RATE Conversion Time 2, 3 Track/Hold Acquisition Time POWER REQUIREMENTS ...
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AD7862 TIMING CHARACTERISTICS A, B Parameter Versions t 3.6 CONV t 0.3 ACQ Parallel Interface ...
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Pin Mnemonic Description Connect 2 DB11 Data Bit 11 (MSB). Three-state TTL output. Output coding is twos complement for the AD7862- 10 and AD7862-3. Output coding is straight (natural) binary for the AD7862-2. 3–6 DB10–DB7 Data Bit ...
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AD7862 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 ...
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CONVERTER DETAILS The AD7862 is a high speed, low power, dual 12-bit A/D converter that operates from a single +5 V supply. The part contains two 4 s successive approximation ADCs, two track/ hold amplifiers, an internal +2.5 V reference ...
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AD7862 currents, as the resistor stage is followed by a high input impedance stage of the track/hold amplifier. For the AD7862-10 7 and For the AD7862-3, ...
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CONVST t 3 BUSY t CONV DATA Figure 5a. Mode 1 Timing Operation Diagram for High Sampling Performance and fourth read pulses, after the second conversion and A0 high, access the result from Channel B (V and ...
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AD7862 respectively). The third and fourth read pulses, after the second conversion and A0 high, access the result from Channel B (V and V respectively). Data is read from the part via a 12-bit B2 parallel data bus with standard ...
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... The output spectrum from the ADC is evaluated by applying a sine wave signal of very low distortion to the V sampled at a 245.76 kHz sampling rate. A Fast Fourier Trans- form (FFT) plot is generated from which the SNR data can be obtained ...
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AD7862 Intermodulation Distortion With inputs consisting of sine waves at two frequencies, fa and fb, any active device with nonlinearities will create distortion products at sum and difference frequencies of mfa ...
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MICROPROCESSOR INTERFACING The AD7862 high speed bus timing allows direct interfacing to DSP processors as well as modern 16-bit microprocessors. Suitable microprocessor interfaces are shown in Figures 14 through 18. AD7862–ADSP-2100 Interface Figure 14 shows an interface between the AD7862 ...
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AD7862 Some applications may require that the conversion be initiated by the microprocessor rather than an external timer. One option is to decode the AD7862 CONVST from the address bus so that a write operation starts a conversion. Data is ...
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DSP MICROPROCESSOR DAC TORQUE & FLUX CONTROL LOOP CALCULATIONS & DAC TWO TO THREE PHASE INFORMATION DAC TORQUE SETPOINT FLUX SETPOINT V TRANSFORMATION TO TORQUE & FLUX CURRENT V A2 COMPONENTS AD7862 *ADDITIONAL PINS OMITTED FOR ...
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AD7862 28-Pin Plastic DIP (N-28) 1.565 (39.70) 1.380 (35.10 0.580 (14.73) 0.485 (12.32 PIN 1 0.060 (1.52) 0.250 0.015 (0.38) (6.35) MAX 0.150 (3.81) MIN 0.200 (5.05) 0.022 (0.558) 0.100 0.070 SEATING 0.125 (3.18) (1.77) (2.54) ...