GENERAL DESCRIPTION

The AD7864 is a high speed, low power, 4-channel simultaneous sampling 12-bit A/D converter that operates from a single +5␣ V supply. The part contains a 1.65 µs successive approximation ADC, four track/hold amplifiers, 2.5 V reference, on-chip clock oscillator, signal conditioning circuitry and a high speed parallel interface. The input signals on four channels are sampled simultaneously, thus preserving the relative phase information of the signals on the four analog inputs. The part accepts analog input ranges of ±10␣ V, ±5 V (AD7864-1), 0 V to 2.5 V, 0 V to 5 V for AD7864-2 and ±2.5␣ V (AD7864-3).

FEATURES

High Speed (1.65 μs) 12-Bit ADC
Four Simultaneously Sampled Inputs
Four Track/Hold Amplifiers
0.35 μs Track/Hold Acquisition Time
1.65 μs Conversion Time per Channel
HW/SW Select of Channel Sequence for Conversion
Single Supply Operation
Selection of Input Ranges:
±10 V, ±5 V for AD7864-1
±2.5 V for AD7864-3
0 V to 2.5 V, 0 V to 5 V for AD7864-2
High Speed Parallel Interface Which Also Allows
Interfacing to 3 V Processors
Low Power, 90 mW Typ
Power Saving Mode, 20 μW Typ
Overvoltage Protection on Analog Inputs

APPLICATIONS

AC Motor Control
Uninterrupted Power Supplies
Data Acquisition Systems
Communications