This document is the technical manual of AD628 high common-mode voltage programmable gain difference amplifier. AD628 is a precision difference amplifier that combines excellent dc performance with high common-mode rejection.
The AD628 is a precision difference amplifier designed to combine excellent DC performance with high common-mode rejection over a wide range of frequencies. It is specifically suited for high voltage current shunt sensing, programmable logic controllers, and analog input front-end signal conditioning. The device allows for the conversion of standard control voltages or currents, such as +5 V, +10 V, ±5 V, ±10 V, and 4 to 20 mA signals, into a single-ended output suitable for single-supply ADCs.
The AD628 operates from both single and dual power supplies and is available in 8-lead SOIC_N or MSOP packages. It features a wideband feedback loop to minimize distortion effects due to capacitor charging of Σ-Δ ADCs and includes a reference pin (V REF) for converting bipolar to single-sided signals. The device supports an input common mode and differential mode operating range of ±120 V.
| Gain Range | 0.1 to 100 V/V |
|---|---|
| Operating Temperature Range | -40°C to +85°C |
| Supply Voltage Range (Dual) | ±2.25 V to ±18 V |
| Supply Voltage Range (Single) | 4.5 V to 36 V |
| Input Common Mode Voltage Range | ±120 V |
| CMRR (DC to 500 Hz) | 75 dB minimum |
| Small Signal Bandwidth | 600 kHz |
| Full Power Bandwidth | 5 kHz |
| Quiescent Current | 1.6 mA |
| Package Types | 8-lead SOIC_N or 8-lead MSOP |
The gain range is adjustable from 0.1 to 100 V/V.
The device supports an input common mode voltage range of ±120 V.
The AD628 operates over the industrial temperature range of −40°C to +85°C.
It supports dual supplies from ±2.25 V to ±18 V and single supplies from 4.5 V to 36 V.