Patent · US Expired

Method of reducing a ripple of a heavy loading pulse frequency modulated voltage regulator

US7071665B2 · kind B2 · utility

11Cited by
9References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 25, 2003
Grant dateJul 4, 2006
Priority date
Expiry dateJul 20, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M1/15
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a pulse frequency modulated (PFM) voltage regulator, a PFM switching signal is provided for converting a DC voltage source to an output voltage. The output voltage is detected. When the output voltage is lower than a predetermined target voltage, a duty cycle of the PFM switching signal is reduced. For example, a minimum OFF-time of the PFM switching signal may be prolonged or a constant ON-time of the PFM switching signal may be shortened. In other words, a period of delivering energy to a capacitor from an inductor may be prolonged or a period of storing energy in the inductor may be shortened. Therefore, a ripple of the output voltage is effectively reduced when the PFM voltage regulator is operated in a heavy loading condition.

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