Patent · US Expired

PWM control apparatus

US6208538A · kind A · utility

29Cited by
8References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 1, 2000
Grant dateMar 27, 2001
Priority date
Expiry dateJun 1, 2020

Classification

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

Abstract

A Pulse Width Modulation (PWM) control circuit is used in a switched-mode power supply (SMPS) having a normal mode and a standby mode, for controlling and regulating the SMPS. An input of the PWM control circuit is arranged to receive a signal indicating an amount of current supplied by the supply. An over-current determining arrangement provides an over-current signal in the event of there being an over-current condition in the signal indicating the amount of current supplied by the supply. A further input of the PWM control circuit receives a regulation signal in the event of there being a regulation output from circuitry coupled to receive power from the SMPS. A logic circuit within the PWM control circuit compares the over-current signal and the regulation signal in order to determine whether the switched-mode power supply is in standby mode or normal mode, thus avoiding the need for a dedicated control pin to indicate standby and normal modes.

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