Patent · US Expired

Voltage/current characteristics control circuit particularly for protecting power transistors

US5210481A · kind A · utility

4Cited by
8References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 17, 1991
Grant dateMay 11, 1993
Priority date
Expiry dateDec 17, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K17/0826
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

Voltage/current characteristics control circuit particularly for protecting power transistors, which comprises at least one power transistor; the emitter terminal of a first transistor is directly connected to the output of the power transistor; the emitter terminal of a second transistor is connected to the first terminal of the power transistor by means of a first resistor. The collector terminal and the base terminal of the first transistor are connected to a current source. The base terminal of the first transistor is connected to the base terminal of the second transistor, and the circuit furthermore comprises a protection circuitry. The circuitry is connected to the collector terminal of the second transistor through a differential stage which comprises a third transistor and a fourth transistor; the third transistor and fourth transistor have a respective second resistor and third resistor arranged in series. Divider means are furthermore provided and are interposed between the second terminal of the power transistor and the base terminals of the third transistor and fourth transistor.

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