Patent · US Expired

Power supply circuit with load protection function

US5774321A · kind A · utility

22Cited by
2References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 1996
Grant dateJun 30, 1998
Priority date
Expiry dateAug 30, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H3/04
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A power supply circuit interrupts power to a load in response to a short-circuit or an open-circuit condition and automatically restores power after a momentary short-circuit. A short-circuit detector monitors the current flowing through the load and generates a short-circuit signal if the current exceeds a predetermined level. An open-circuit detector monitors the load voltage and generates an open-circuit signal if the voltage exceeds a predetermined level. A latch converts the short-circuit signal to a latch signal. A logic unit combines the latch signal with the open-circuit signal and a pulse signal from a pulse generator to generate a drive signal. A driver uses the drive signal to control a switch which is connected between the power source and the load to interrupt power to the load. During a short-circuit, a timer generates a periodic pulse signal that toggles the latch signal and intermittently restarts the power to the load. If the short-circuit was of short duration, power is restored to the load. If the short-circuit persists, the power supply circuit continues to intermittently restore power to the load until the short-circuit is removed. The logic unit also generates…

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