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:
Jul. 23, 2013
Filed:
May. 23, 2011
Zhiye Zhang, San Jose, CA (US);
Kuang Ming Chang, Fremont, CA (US);
Zhiye Zhang, San Jose, CA (US);
Kuang Ming Chang, Fremont, CA (US);
Alpha and Omega Semiconductor Incorporated, Sunnyvale, CA (US);
Abstract
A control circuit for a switching regulator implements constant on-time control scheme with synchronous rectification and applies dual control loops to improve light load efficiency and enhance transient response. In one embodiment, the control circuit includes a first control loop configured to control a one-shot timer to generate a control signal to turn on the main switch when the feedback voltage is below a first reference voltage and a minimum off-time duration has expired. The control circuit further includes a second control loop configured to control the one-shot timer to generate the control signal to turn on the main switch when the feedback voltage is below a second reference voltage and the minimum off-time duration has expired and a low-side current signal has a first state indicative of a light load condition at the output node.