Patent · US Expired

Power supply with multiple isolated regulators and isolation mode

US5659208A · kind A · utility

33Cited by
3References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 14, 1995
Grant dateAug 19, 1997
Priority date
Expiry dateJul 14, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M3/285
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A method of operating a redundant power supply is disclosed wherein two or more converters are separately connected to a common output node through separate diodes to isolate the converters and allow the outputs to be separately tested for diagnostic purposes. The diodes are selectively bypassed by connecting drain-to-source paths of P-channel MOS field-effect transistors separately across the diodes. During the diagnostic mode of operation, a controller shuts off the MOS transistors, so the diodes are effective in isolating the converters. During the bypass mode of operation, the transistors are turned on by the controller so the diodes are bypassed and their forward voltage drop does not appear in the circuit and so power dissipation is reduced. It is noted that the P-channel MOS transistor is connected such that it's intrinsic PN-junction diode conducts in a forward direction in parallel with the isolation diode, so that isolation during the diagnostic mode is not cancelled. The controller switches from the diagnostic mode to the bypass mode after a delay allowing the diagnostics routine to complete.

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