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:
Jun. 12, 2012
Filed:
Feb. 19, 2009
Liang Yan, Milpitas, CA (US);
Xiaoyan Wang, Milpitas, CA (US);
Jun Zheng, Shenzhen, CN;
Junjie Zheng, Santa Clara, CA (US);
Clarita Poon, Pleasanton, CA (US);
Liang Yan, Milpitas, CA (US);
Xiaoyan Wang, Milpitas, CA (US);
Jun Zheng, Shenzhen, CN;
Junjie Zheng, Santa Clara, CA (US);
Clarita Poon, Pleasanton, CA (US);
iWatt Inc., Campbell, CA (US);
Abstract
A switching power converter detects low load conditions based on the ratio of a first peak current value for peak current switching in constant voltage regulation mode to a second peak current value for peak current switching in constant current regulation mode. The power supply load is considered to have a low load if the ratio is lower than a predetermined threshold. Once a low load condition is detected, the switching frequency of the switching power converter is reduced to a level that minimizes switching loss in the power converter. In addition, the switching power converter also adjusts the switching frequency according to the sensed input line voltage. An offset is added to the switching period to reduce the switching frequency of the switching power converter, as the input line voltage is increased.