Patent · US Expired

Two-terminal temperature-compensated current source circuit

US4792748A · kind A · utility

30Cited by
12References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 17, 1987
Grant dateDec 20, 1988
Priority date
Expiry dateNov 17, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S323/907
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A two-terminal temperature-compensated current source includes a first transistor having its emitter connected to a first terminal, its base connected to the base of a second transistor, and its collector coupled to a current mirror. The second transistor has its emitter coupled to the first terminal by a first resistor and its collector coupled to the current mirror. A second resistor is coupled between the first terminal and the base of the first transistor. The current mirror is coupled between a second terminal and the collectors of the first and second transistors so that all current supplied to the current mirror from the second terminal flows into the collectors of the first and second transistors. A third transistor has its base coupled to the collector of the first transistor, its emitter coupled to the base of the first transistor, and its collector coupled to the second terminal. The current in the first resistor has a positive temperature coefficient, and the current in the second resistor has a negative temperature coefficient. The temperature coefficient of the total current flowing between the first and second terminals is adjusted by adjusting the ratio between the …

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