Analysis of Slew Rate and Settling Time in Two Stage CMOS Operational Amplifiers with Cascode Compensation
Subject Areas : electrical and computer engineeringhannane Gholamntaj 1 , habib Adarang 2 , seyed saleh Mohseni 3 , seyed saleh Ghoreishi 4
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Keywords: Settling time, slew rate, slewing, cascode compensation, operational amplifier, step response,
Abstract :
Slew rate and settling time are the important parameters in opamps with feedback. In this paper, the slew rate and settling time of the fully differential two stages folded cascade architecture amplifier with cascade compensation is analyzed. An important characteristic of the proposed analytical model is that the behavior of the transistors is examined in detail after applying the step in the input, and it is shown that the settling time as well as slew rate would depend on the size of the input step. The performed analysis can be beneficial for design and manual calculations in integrated circuits. Moreover, circuit level simulation is used to validate the analytical results with particular emphasis on slew rate and settling time. Simulations results show excellent conformance between the analytical equations and the simulation results.
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