High-performance swing-enhanced floating inverter amplifier using
correlated level shifting technique
Abstract
An improved swing-enhanced floating-inverter amplifier (SEFIA) using the
correlated-level-shifting (CLS) technique is presented, simultaneously
achieving both high gain and high output swing. The proposed SEFIA uses
a reused capacitor to replace the dynamic biasing capacitor and input
coupling capacitor. One of the two reservoir capacitors, which supplies
power to the amplifier in the auto-zero phase, is also reused in the
level shifting phase. Post-layout simulation results show that in the
180 nm CMOS process; the DC gain remains above 73dB for clock
frequencies between 50 kHz to 400 kHz. Compared to conventional FIA with
CLS, the proposed SEFIA with a 1.8V supply achieves the 1.54 times
output swing increase at a clock frequency of 250 kHz. The CLS technique
boosts the DC gain of the proposed SEFIA from 50dB to 74.6dB.