The AD8638/AD8639 are single and dual wide bandwidth, auto-zero amplifiers featuring rail-to-rail output swing and low noise. These amplifiers have very low offset, drift, and bias current. Operation is fully specified from 5 V to 16 V single supply (±2.5 V to ±8 V dual supply).The AD8638/AD8639 provide benefits previously found only in expensive zero-drift or chopper-stabilized amplifiers. Using the Analog Devices, Inc., topology, these auto-zero amplifiers combine low cost with high accuracy and low noise. No exter-nal capacitors are required. In addition, the AD8638/AD8639 greatly reduce the digital switching noise found in most chopper-stabilized amplifiers.With a typical offset voltage of only 3 μV, drift of 0.01 μV/°C, and noise of 1.2 μV p-p (0.1 Hz to 10 Hz), the AD8638/AD8639 are suited for applications in which error sources cannot be tolerated. Position and pressure sensors, medical equipment, and strain gage amplifiers benefit greatly from nearly zero drift over their operating temperature ranges. Many systems can take advantage of the rail-to-rail output swing provided by the AD8638/AD8639 to maximize signal-to-noise ratio (SNR).

The AD8638/AD8639 are specified for the extended industrial temperature range (−40°C to +125°C). The single AD8638 is available in tiny 5-lead SOT-23 and 8-lead SOIC packages. The dual AD8639 is available in 8-lead MSOP, 8-lead SOIC, and 8-lead LFCSP packages. See the Ordering Guide for automotive grades.