AD8231

The AD8231 is a low drift, rail to rail, instrumentation amplifier with software programmable gains of 1, 2, 4, 8, 16, 32, 64 or 128. The gains are programmed via digital logic or pin strapping.

The AD8231 is ideal for applications that require precision performance over a wide temperature range, such as industrial temperature sensing and data logging. Because the gain setting resistors are internal, maximum gain drift is only 10 ppm/ºC. Because of the autozero input stage, maximum input offset is 25 uV and maximum input offset drift is just 50 nV/ºC. CMRR is also guaranteed over temperature: 80 dB for G=1, increasing to 122 dB at a gain of 128. Voltage noise is just 0.7 uV p-p (0.01 Hz to 10 Hz).

The AD8231 also includes an uncommitted op amp which can be used for additional gain, differential signal driving or filtering. Like the in amp, the op amp has an autozero architecture, rail to rail input, and rail to rail output.

The AD8231 includes a shutdown feature that reduces current to 1 uA and makes the amplifier output high impedance. This allows easy multiplexing of multiple amplifiers without additional switches.

The AD8231 is specified over the extended industrial temperature range of -40°C to +125°C. It is available in a 4mm x 4mm 16-Lead LFCSP (Chip Scale) package.