AD628

High Common-Mode Voltage, Programmable Gain Difference Amplifier AD628 02992-001 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 controls Motor controls 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. A reference pin (VREF) provides a dc offset for converting bipolar to single-sided signals. The AD628 converts +5 V, +10 V, ±5 V, ±10 V, and 4 to 20 mA input signals to a single-ended output within the input range of single-supply ADCs. The AD628 has an input common mode and differential mode operating range of ±120 V. The high common mode, input impedance makes the device well sui...