Patent · US Expired

Class A operational amplifier with area efficient MOS capacitor frequency compensation

US5731739A · kind A · utility

10Cited by
3References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 13, 1996
Grant dateMar 24, 1998
Priority date
Expiry dateJun 13, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F1/086
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An operational amplifier with MOSFET's configured as capacitors provide frequency compensation over a large range of input frequencies is described. The operational amplifier has an differential amplifier stage with an inverting and an noninverting input. The difference of signals placed at the inverting and the noninverting inputs are amplified and place at the input of a folded cascode amplifier stage. The output of the folded cascode amplifier stage is the input to a linear amplifier stage. The output of the linear amplifier stage is connected to external loading circuitry. A first frequency compensation capacitor is connected between the output of the linear amplifier stage and a noninverted input of the folded cascode amplifier. A second frequency compensation capacitor is connected between the output of the linear amplifier stage and a virtual ground within the folded cascode amplifier stage. A power distribution and biasing network provides a power supply voltage source, a ground reference potential, a substrate voltage source, and a plurality of biasing voltage sources to said differential amplifier stage, said folded cascode amplifier stage, and said linear amplifier stage…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.