Patent · US Expired

Variable frequency soft switching power supply with reduced noise and improved power factor

US6061253A · kind A · utility

39Cited by
2References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 3, 1998
Grant dateMay 9, 2000
Priority date
Expiry dateDec 3, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B70/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A switching power supply uses zero-current and zero-voltage switching to reduce switching noise. A main switch and an auxiliary switch channel current and voltage between various component paths to maintain a DC output voltage while switching in zero-current or zero-voltage states. Switch ON-OFF time ratios are controlled with a simple scheme to improve the circuit power factor. The switching rate can be set to arbitrary frequencies, with switch ON time and OFF time being controlled independently. This scheme permits efficient driving of a load that is substantially less than the rated load, as generally found in portable TV circuits. The switches and control functions can be implemented on an integrated circuit.

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