A Low-Voltage, High Speed, High Gain OTA in a Digital 90nm CMOS Technology

This paper presents the design and simulation of a lowvoltage high-speed and high-gain fully differential transconductance amplifier (OTA) in a digital 90nm CMOS technology. The OTA uses a folded cascade amplifier with gainboost technique as the first stage and a common-source amplifier with an active load as the second stage. Simulation results show a DC gain of 83dB, unity gain bandwidth of 950MHz and phase margin of 108 degrees. The settling time is 3ns and the OTA consumes 2mW from a 1V power supply.