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:
Apr. 14, 2009
Filed:
May. 02, 2006
Kwan-jen Chu, Hsinchu, TW;
Chung-lung Pai, Hsinchu, TW;
Yuan-huang Cheng, Pingdung, TW;
Jing-meng Liu, Hsinchu, TW;
Kwan-Jen Chu, Hsinchu, TW;
Chung-Lung Pai, Hsinchu, TW;
Yuan-Huang Cheng, Pingdung, TW;
Jing-Meng Liu, Hsinchu, TW;
Richtek Technology Corp., Hsinchu, TW;
Abstract
In a fly-back voltage converter that includes a transformer to transform a primary current to a secondary current and a switch serially coupled to the primary winding to switch the primary current in response to a control signal, a detection signal is produced by comparing the secondary current with two threshold values after the primary current is switched off to trigger the next on-time cycle of the switch. Once the secondary current is detected to be greater than a first threshold value, it is determined that the secondary current has been switched on, and until the secondary current is detected to be lower than a second threshold value, it is determined that the secondary current is to be switched off. The hysteresis range of the threshold values prevents error detection of the secondary current.