Full differential low voltage low power operational amplifier with 308 MHz GBW for switched capacitor applications

Switched capacitor circuits play an important role in analog and signal processing circuits. These circuits can realize large group of functions such as sampling, filtering anddigitalization functions. Also these circuits are appropriate in CMOS technology for implementing Digital Signal Processing(DSP) block integration. For this purpose, the paper proposes a fully differential low voltage low power operational amplifier using positive feedback which improves DC gain, unity gainfrequency and settling time. The proposed amplifier can be used in switched capacitor filters. This amplifier has been designed for180 nm CMOS technology @ 1.2 V. Simulation results based on HSPICE circuit simulator show 62 dB, 308 MHz and 510 μW as DC gain , GBW and power consumption respectively.

Keywords:

amplifier , switched capacitor , positive feedback , low voltage low power Introduction