The MAX4162/MAX4163/MAX4164 are single/dual/quad, micropower operational amplifiers that combine an exceptional bandwidth to power consumption ratio with true rail-to-rail inputs and outputs. They consume a mere 25μA quiescent current per amplifier, yet achieve 200kHz gain-bandwidth product and are unity-gain stable while driving any capacitive load. The MAX4162/ MAX4163/MAX4164 operate from either a single supply (2.5V to 10V) or dual supplies (±1.25V to ±5V), with an input common-mode voltage range that extends 250mV beyond either supply rail. These amplifiers use a proprietary architecture to achieve a very high input commonmode rejection ratio without the midswing nonlinearities present in other rail-to-rail op amps. This architecture also maintains high open-loop gain and output swing while driving substantial loads.