Design and Analysis of Robust Two Stage Op-Amp using 90 nm CMOS Technology for Biomedical Applications

In recent years, the CMOS operational amplifier has become an indispensable component in analog and mixed-mode circuits. This study focuses on the design and analysis of CMOS-based operational amplifiers with large unity gain-bandwidth, moderate gain, and low power dissipation for medical applications. In this study, we were able to enhance the gain band-width of CMOS operational amplifiers with 32 MHz for one design and 50 MHz bandwidth for another design. The op-amp with nulling resistor compensation displayed the unity gain bandwidth (UGB) of about 32.74 MHz and DC gain of about 72.4 dB and power dissipation is around 138.63 µW. The op-amp with current buffer compensation yielded the UGB of about 50.25 MHz and DC gain of about 61.09 dB and power dissipation is around 183.65 µW. The circuits were designed on Cadence Virtuoso environment GPDK 90-nm CMOS technology.