Patent · US Expired

Soft start of a switching power supply system

US6683442B1 · kind B1 · utility

6Cited by
7References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 15, 2002
Grant dateJan 27, 2004
Priority date
Expiry dateAug 15, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S323/901
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A synch FET power supply uses a plurality of electronic switches to periodically connect the primary of a transformer to a direct current input source of power to generate a time varying magnetic field. The time varying magnetic field is coupled to two secondary windings. An electronic switch connected to each secondary winding periodically connects its secondary to the other output terminal. A reference voltage is applied to the control circuits, and the control circuits adjust the switches so that the output voltage tracks the reference voltage. Logic AND gates control the “turn on” signals to the electronic switches in the secondary circuits so that the secondary windings are not connected to an output terminal until a “synch FET enable” signal is applied to the AND gates. During soft start, the secondary windings remain disconnected from an output terminal until a “synch FET enable” signal is applied to an input of the logic AND gates, and since the secondary windings do not provide a complete circuit between the output terminals, no power flows into the synch FET power supply even though a back bias is applied between the output terminals by…

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