A 1.8-V Fully Differential Two-Stage CMOS OTA with 2.8V-Swing for High Speed Pipelined ADC

Abstract

A low power, high dc gain, high speed and large swing operational transconductance amplifier (OTA) is proposed. The OTA achieve 104dB dc gain and 3.65GHz gain bandwidth product (GBW) and only dissipates 38mW under 1.8V power supply. It is fabricated in 0.18um CMOS process and occupies 0.146mm2. It is integrated in a 14b 50MSPS pipeline ADC which delivers up to 82.3dBc spur-free dynamic range (SFDR) and with 2.4MHz input tone and can be used in many communication systems where fast and precise date converting is required.