Operational amplifier modelling for high speed sampled data applications

摘要

A pair of symmetrical and versatile equivalent circuits suitable for two pole single and two stage operational amplifiers is presented. The improved accuracy of the new equivalent circuits is necessary when designing the compensation network of high speed amplifiers to minimise their very strongly phase-dependent settling time, which is important for sampled data analogue signal processing circuits. These models also identify a critical effective capacitance, which is shown to govern the settling behaviour of the operational amplifier.