Patent · US Expired

Protective device electronic semiconductor component

US4355344A · kind A · utility

16Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 25, 1980
Grant dateOct 19, 1982
Priority date
Expiry dateFeb 25, 2000

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/0002
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

To protect a discrete electronic component such as a bipolar transistor or a field-effect transistor against destructive current surges, one or two ancillary transistors are formed in the same semiconductor body which has a major portion thereof overlain by an output electrode constituting a variable-voltage terminal connected to a load. This major portion, acting as the collector of the bipolar transistor (or of two such transistors in a Darlington configuration) or as the drain of the FET to be protected, also forms the collector of each ancillary transistor whose emitter is grounded through a constant-current generator or through a resistor. The emitter potential of a single ancillary transistor, or the potential difference of the emitters of two such transistors of mutually different current densities, varies as a function of temperature and is compared with a reference voltage to apply, in the event of an overload, an inhibiting signal to a driver stage for blocking or limiting the conduction of the protected component.

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