Patent · US Expired

Driver circuit for use with inductive loads or the like

US4358812A · kind A · utility

10Cited by
4References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 4, 1981
Grant dateNov 9, 1982
Priority date
Expiry dateFeb 4, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H47/325
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An integrated circuit is operative to produce an output current to a load and for switching the output current when a predetermined peak magnitude of load current is reached to a lower predetermined constant value. The circuit includes an internal power stage rendered conductive for producing maximum load current through the external load which is connected in series therewith in response to an internally generated reference current. The power stage comprises a multi-emitter power transistor with each emitter coupled to a respective emitter ballast resistor such that the load current through one of the resistors may be sensed and compared to the reference current to cause the magnitude of this reference current to be switched from a maximum value to a minimum value when the sensed current is representative of the peak magnitude value of current to thereby reduce the load current until the magnitude thereof is representative of the lower level of reference current.

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