Bulk-driven flipped voltage follower

Abstract

A voltage buffer so-called the bulk-driven flipped voltage follower is presented. This proposal is based on the Flipped Voltage Follower (FVF) technique, but a bulk-driven MOSFET with the replica-biased scheme is utilized for the input device to eliminate the DC level shift. The proposed buffer has been designed and simulated with a 0.35µm CMOS technology. The input current and capacitance of our proposal are 1.5pA and 9.3fF respectively, and with 0.8V peak-to-peak 500kHz input, the total harmonic distortion is 0.5% for a 10pF load. This circuit can operate from a single 1.2V power supply and consumes only 2.5µA.