A high-performance 1.2 V-99 μW rail-to-rail CMOS class AB amplifier

This paper presents a compact, reliable 1.2 V low-power rail-to-rail class AB operational amplifier (OpAmp) suitable for integrated battery powered systems which require rail-to-rail input/output swing and high slew-rate while maintaining low power consumption. The OpAmp, fabricated in a standard 0.18 μm CMOS technology, exhibits 86 dB open loop gain and 97 dB CMRR. Experimental measurements prove its correct functionality operating with 1.2 V single supply, performing very competitive characteristics compared with other similar amplifiers reported in the literature. It has rail-to-rail input/output operation, 5 MHz unity gain frequency and a 3.15 V/μs slew-rate for a capacitive load of 100 pF, with a power consumption of 99 μW.