Low Cost, Single-Supply Differential Amplifier

The AD626 is a low cost, true single supply differential amplifier designed for amplifying and low-pass filtering small differential voltages from sources having a large common-mode voltage.

The AD626 can operate from either a single supply of +2.4 V to +10 V, or dual supplies of ±1.2 V to ±6 V. The input common-mode range of this amplifier is equal to 6 (+VS - 1 V) which provides a +24 V CMR while operating from a +5 V supply. Furthermore, the AD626 features a CMR of 90 dB typ.

The amplifier's inputs are protected against continuous overload of up to 50 V, and RFI filters are included in the attenuator network. The output range is +0.03 V to +4.9 V using a +5 V supply. The amplifier provides a preset gain of 10, but gains between 10 to 100 can be easily configured with an external resistor. Furthermore, a gain of 100 is available by connecting the G = 100 pin to analog ground. The AD626 also offers low-pass filter capability by connecting a capacitor between the filter pin and analog ground.

The AD626A and AD626B operate over the industrial temperature range of -40°C to +85°C. The AD626 is available in two 8-pin packages: a plastic mini-DIP and SOIC.

* Pin Selectable Gains of 10 and 100

* True Single-Supply Operation

Single-Supply Range of +2.4V to +10V

Dual-Supply Range of ±1.2V to ±6V

Wide Output Voltage Range of 30 mV to 4.7V

* Includes Input Protection

Series Resistive Inputs

(RIN = 200 kΩ)

RFI Filters Included

Allows 50V Continuous Overload

* Optional Low-Pass Filtering

* Excellent DC Performance

Low Input Offset Voltage: 500 µV Max

Large Common-Mode Range:

0V to +54V

Low Power: 1.2 mW (VS = +5V)

Good CMR of 90 dB Typ

* AC Performance

Fast Settling Time: 24 µs (0.01%)