All Digital Transistors High Gain Operational Amplifier Using Positive Feedback Technique
Mezyad M. Amourah and Randall L. Geiger
Dept. of Electrical and Computer Engineering
Iowa State University, Ames, IA, 50011 USA
Abstract:
New all digital-transistor CMOS very high DC-gain amplifiers that use internal positive-feedback technique are presented. These structures don't require perfect matching of transistors to achieve the very high DC gain, and have a very low gain sensitivity to output swing. An implementation of a sample and hold circuit constructed using one of the proposed amplifiers is described. Special layout pattern is used to cut the parasitic capacitance.