Method for Increasing Fast Response of the Operational Amplifiers in the Inverting Connection with an Input Stage of the Dual-Input-Stage Class and a Push-Pull “Folded” Cascode

Abstract

A new method for connecting differentiating correction circuits in the inverting connection of the high-speed operational amplifiers (Op-Amp) implemented on the basis of a push-pull “folded” cascode is developed and studied. Forcing the processes of recharging an integrating balancing capacitor responsible for the formation of the logarithmic amplitude-frequency characteristic and ensuring the specified phase stability margin of the Op-Amp is provided in the suggested circuits. At the same time, the maximum slew rate increases significantly (by 10-100 times) up to 1000 $\mathrm{V}/\mu \mathrm{s}-2000\ \mathrm{V}/\mu \mathrm{s}$, The results of computer simulation of CMOS and BJT high-speed Op-Amps in the inverting drivers of the high-speed ADCs implemented on the input stages of the dual-input-stage class are presented.