Patent · US Expired

Rail to rail operational amplifier output stage

US5546045A · kind A · utility

16Cited by
10References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 19, 1995
Grant dateAug 13, 1996
Priority date
Expiry dateApr 19, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F2203/45366
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An integrated circuit output stage is intended for use with an operational amplifier. The output is capable of driving capacitive load to within a V.sub.SAT of the power supply rails. The complementary output transistors are driven by way of a combination of buffers and complementary differential amplifiers which act to bias the stage in class AB. The quiescent current is stabilized and controlled, in part, by simple resistor rationing. The output transistor saturation is sensed and a current limit is imposed so that hard saturation is avoided. Frequency compensation is achieved in a manner that responds to output transistor saturation so as to improve the high frequency transient response. Feedforward capacitors are also included to further improve high frequency response.

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