Using the Gm-C compensation technique, an ultra-low-power two-stage operational transconductance amplifier (OTA) with rail-to-rail input/output swing is presented. The input stage of the proposed OTA has the benefit of transconductance enhancement compared to the conventional OTA with the same power consumption and silicon area. Simulation results in a 0.18 μm CMOS technology show a DC gain enhancement of 9.5 dB as well as 88% improvement in gain bandwidth compared to the conventional folded cascode input stage structure.
