Patent · US Expired

DC/DC converter incorporating a skip mode regulator

US6359797B1 · kind B1 · utility

15Cited by
5References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 6, 2000
Grant dateMar 19, 2002
Priority date
Expiry dateJul 6, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M1/146
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The invention relates to a DC/DC converter operating on the principle of a charge pump, comprising at least one charge pump capacitor and several controllable switches connected thereto. The switches are actuated by a control circuit with an oscillator. A skip mode comparator signals the charge pump alternatingly ON and OFF depending on the condition of the output voltage of the converter. Prior art converters featured high output current spikes and a heavy output voltage ripple. The converter in accordance with the invention reduces these problems by a regulator circuit which receives the control signal of the comparator and converts it into a signal characterizing the momentary ON/OFF duration ratio of the charge pump with which it controls the ON resistance of at least one of the switches so that the ON/OFF duration ratio of the charge pump can be set to a predetermined design value, at which the output current spikes of the charge pump are reduced. Provided parallel to this switch is a further small switch whose ON resistance is not controlled to thus ensure a small idle current of the charge pump at a low load.

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