A 1.5-V high drive capability CMOS op-amp

摘要

A novel CMOS operational amplifier with a 1.5 V power supply isnpresented. It is based on a folded-mirror transconductance amplifier andna high-efficiency output stage. The amplifier achieves an open-loop gainnand a gain-bandwidth product higher than 65 dB and 1 MHz, respectively.nIn addition, a 1 V peak-to-peak output voltage into a 500 Ω and 50npF output load is provided with a total harmonic distortion of -77 dB.nThis performance was achieved using maximum aspect ratios of 120/1.2 andn360/1.2 for the NMOS and PMOS transistors, respectively, and a quiescentncurrent as low as 60 ΜA for the driver transistors. The amplifier wasnimplemented in a standard 1.2 Μm CMOS process with threshold voltagesnaround 0.8 V. It dissipates less than 300 ΜW