Design of Two-Stage CMOS Operational Amplifier for Sigma-Delta ADC

In this paper a design of two-stage CMOS operational amplifier for sigma-delta ADC is presented, which operates at ±1.8 V power supply using 180 nm technology. This two-stage CMOS OP-AMP has been designed to indicate a unity gain frequency of 18.2MHz and indicates a gain of 71.27 dB. The design and simulation part has been done on Cadence Custom IC CAD. The simulated results are encouraging and has better performance.