Patent · US Expired

Low voltage operational amplifier and method

US5699015A · kind A · utility

17Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 19, 1996
Grant dateDec 16, 1997
Priority date
Expiry dateMar 19, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F3/3001
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

Low voltage operational amplifier (10) operates in a voltage range of one to eight volts over a temperature range of 0.degree. to 70.degree. centigrade. Op amp input stage (12) uses N-channel depletion-mode MOSFETs to provide amplification of the differential input and maintain constant transconductance. Source follower MOSFET (13) provides unity gain in transferring the AC signal, STAGE-1 OUTPUT, to the base of current sinking transistor (18). Sink control circuit (14) and source control circuit (22) generate the base drive currents for transistors (18) and (24). The signal at the output of MOSFET (13) either causes the sink transistor (18) to sink current or the signal to be transposed by means of a translinear loop (16) and causes the source transistor (24) to source current.

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