AD8231TCPZ-EP-R7

The AD8231-EP 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-EP 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/°C for gains of 1 to 32. Because of the auto-zero input stage, maximum input offset is 15 μV and maximum input offset drift is just 50 nV/°C. CMRR is 80 dB for G = 1, increasing to 110 dB at higher gains. The AD8231-EP also includes an uncommitted op amp that can be used for additional gain, differential signal driving, or filtering. Like the in-amp, the op amp has an auto-zero architecture, rail-to-rail input, and rail-to-rail output. The AD8231-EP includes a shutdown feature that reduces current to a maximum of 1 μA. In shutdown, both amplifiers also have a high output impedance, which allows easy multiplexing of multiple amplifiers without additional switches. The AD8231-EP is specified over the temperature range of -55°C to +125°C. It is available in a 4 mm×4 mm 16-lead LFCSP.

Applications

• industrial temperature sensing
• data logging

Key features

• Digitally/pin-programmable gain G = 1, 2, 4, 8, 16, 32, 64, or 128
• Specified from -55°C to +125°C
• 50 nV/°C maximum input offset drift
• 10 ppm/°C maximum gain drift
• Excellent dc performance
• 80 dB minimum CMR, G = 1
• 15 μV maximum input offset voltage
• 500 pA maximum bias current
• 0.7 μV p-p noise (0.1 Hz to 10 Hz)
• Good ac performance
• 2.7 MHz bandwidth, G = 1
• 1.1 V/μs slew rate
• Rail-to-rail output
• Shutdown/multiplex
• Extra op amp
• Single-supply range: 3 V to 6 V
• Dual-supply range: ±1.5 V to ±3 V