GENERAL DESCRIPTION

The AD628 is a precision difference amplifier that combines excellent dc performance with high common-mode rejection over a wide range of frequencies. When used to scale high voltages, it allows simple conversion of standard control voltages or currents for use with single-supply ADCs. A wideband feedback loop minimizes distortion effects due to capacitor charging of Σ-Δ ADCs.

FEATURES

High common-mode input voltage range

  ±120 V at VS= ±15 V

Gain range 0.1 to 100

Operating temperature range: −40°C to ±85°C

Supply voltage range

  Dual supply: ±2.25 V to ±18 V

  Single supply: 4.5 V to 36 V

Excellent ac and dc performance

Offset temperature stability RTI: 10 μV/°C maximum

Offset: ±1.5 V mV maximum

CMRR RTI: 75 dB minimum, dc to 500 Hz, G = +1

APPLICATIONS

High voltage current shunt sensing

Programmable logic controllers

Analog input front end signal conditioning

  +5 V, +10 V, ±5 V, ±10 V, and 4 to 20 mA

Isolation

Sensor signal conditioning

Power supply monitoring

Electrohydraulic control

Motor control