Comparative Experimental Analysis of different Op-amps using 180nm CMOS Technology

Operational amplifiers used in voltage follower, switched-capacitor, digital to analog converter is the basic blocks of analog systems. An operational amplifier design depends on the supply voltage and gain. The digital circuits greatly benefits from reduction of size and supply voltage while analog circuits depend on the parameters like offset, noise, gain, power consumption and bandwidth for greater benefits. Current mode circuits have high slew rate and wider bandwidth. Therefore, current mode circuits are more preferable than voltage mode circuits as it has a high slew rate and wider bandwidth. The dynamic range of low power operational amplifier is limited by small currents. One of the techniques to make Op-amp very efficient with low power supply voltage without degrading the characteristics use of effective current mirrors. In this paper the various Operational amplifiers with different current mirror loads are analysed and compared. The parameters of Operational amplifier are considered and compared in cadence virtuoso using 180nm technology.