Active Compensation of CFOA based Non-Inverting Amplifier

Abstract: In this paper, we consider active compensation techniques using a voltage buffer to enhance the bandwidth of current feedback operational amplifier (CFOA) based finite gain non-inverting voltage amplifier. The use of feed forward capacitor in addition to voltage buffer is shown to achieve minimum phase error in the resulting frequency response. The proposed circuits require one additional CFOA/ capacitor. The effect of finite output impedance at z terminal, input resistance at x terminal, and current mirror pole of the CFOA are studied. The circuits considered have been simulated in PSPICE using a behavioral macro-model of the CFOA as well as that of a practical CFOA AD 844.

Keywords: Current-feedback op-amp (CFOA); Active compensation;Passive compensation.