A frequency compensation technique for the improvement of unity gain bandwidth (UGB) and power supply rejection ratio (PSRR) of two stage operational amplifiers is presented in this paper. Performance of proposed op-amp is compared with classical miller compensated op-amp and op-amp proposed by G. Blakiewicz [13]. The technique exploits the triode mode operation of a MOSFET in the compensation stage which leads to the improvement in the UGB and Power Supply Rejection Ratio (PSRR). Small signal analysis for these parameters is carried out and theoretical improvements are verified through simulations in cadence VIRTUSO environment using UMC 0. 18 µm CMOS process technology.

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Miller Compensation Triode Mode Mosfet Unity Gain Bandwidth Power Supply Rejection Ratio Phase Margin Op-amp