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:
Dec. 28, 2004
Filed:
Jun. 18, 2003
Ta-yung Yang, Milpitas, CA (US);
Chem-Lin Chen, Taipei, CA (US);
Jenn-yu G. Lin, Taipei, TW;
Song-Yi Lin, Taipei, TW;
Systems General Corp., Taipei Hsien, TW;
Abstract
The present invention provides a primary-side regulated PWM controller with improved load regulation. In every PWM cycle, a built-in feedback voltage samples and holds a flyback voltage from the auxiliary winding of the transformer via a sampling switch and generates a feedback voltage accordingly. A bias current sink pulls a bias current that is proportional to the feedback voltage. Via a detection resistor, the bias current will produce a voltage drop to compensate the voltage drop of an output rectifying diode as the output load changes. According to the present invention, the bias current can enable the PWM controller to regulate the output voltage very precisely without using a secondary feedback circuit.