A Study on the Design of Broadband Operational Amplifier and Circuit Simulation Using GaAs MESFETs

In this paper, a high gain operational amplifier using GaAs MESFETs that have intrinsically the low voltage gain(gmrds) at high frequencies has been designed and simulated. The amplifier is composed of a differential input stage with multi-current path and is internally compensated. An open loop gain of 35.7dB a 500 MHz and 51dB at 100MHZ was archived by using gain stage with self-bootstrap. The result of Pspice simulation show that designed OP AMP has a higher gain at high frequncies and the improved phase margin of 80 by using internal compensation capacitor.ope