The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 21, 2012
Filed:
Dec. 21, 2011
Roger Colbeck, Ottawa, CA;
Paul Demone, Kanata, CA;
Anthony Peter Ernest Reinberger, Nepean, CA;
Power Integrations, Inc., San Jose, CA (US);
Abstract
An apparatus includes a control unit to generate a control signal to control a duty cycle of a PWM switching signal that controls a switch in a PFC converter. The control unit includes a PWM converter to produce a PWM signal responsive to an output voltage of the PFC converter. A switching circuit switches a current representing an input current of the PFC converter in response to the PWM signal. A circuit generates the control signal in response to the switched current. The control unit includes an amplifier that receives a current sense signal and provides the current representing the input current of the PFC converter. An offset unit generates a variable offset signal to generate the control signal. The offset unit provides the offset signal as an offset current for offsetting a current at an input of the amplifier.