Optimum nested Miller compensation for low-voltage low-power CMOS amplifier design

Abstract

An optimum structure of nested Miller compensation (NMC) is developed, The developed structure using feed-forward transconductance stage and null resistor on NMC, called NMCFNR, solves the bandwidth reduction and poor transient response problems of low-voltage low-power NMC amplifiers. For comparison, amplifiers compensated by NMC and NMCFMR have been fabricated. Experimental results show that NMCFNR improves the gain-bandwidth product, slew rate and settling time by more than three times with 8 degrees increase on the phase margin and no increase on the power consumption. Moreover, it improves the negative power supply rejection ratio by at least 54dB. The die area of the NMCFNR amplifier is about hall of that of the NMC amplifier