A 130nm CMOS Programmable Operational Amplifier

In this work we present a programmable 1.2 V operational amplifier (OpAmp) realized in a standard 130 nm CMOS technology. The OpAmp is based on a 3 V rail-to-rail input/output topology. The experimental results show the feasibility of using higher voltage topologies in conjunction with multi-threshold (multi-Vth) process options for low voltage designs. The programming range extends from a low-noise to a low-power mode. In addition, a constant-gm stage has been added to the rail-to-rail input. In low-noise mode the OpAmp has a low input thermal noise voltage of 5.1 nV/¿Hz and in low-power mode a power consumption of only 203 ¿W. Over the whole programming range the OpAmp maintains unity-gain stability with its phase margin varying between 58° and 62°.