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:
Oct. 25, 2011
Filed:
Apr. 09, 2009
Yajiang Zhu, Shanghai, CN;
Zheng Ying, Shanghai, CN;
Xianfeng Liu, Shanghai, CN;
Yanping Wang, Shanghai, CN;
Yajiang Zhu, Shanghai, CN;
Zheng Ying, Shanghai, CN;
Xianfeng Liu, Shanghai, CN;
Yanping Wang, Shanghai, CN;
Abstract
A controller for a switching mode power supply includes two semiconductor chips. The first semiconductor chip has a high-voltage startup transistor coupled to a high voltage supply input terminal and configured to provide a charging current in a startup phase or protection mode of a switching mode power supply (SMPS) and to provide substantially no current in a normal operation phase of the SMPS. The second semiconductor chip has a control circuit for controlling the switching mode power supply. The second semiconductor chip also has first and second on-chip high-voltage resistors coupled to the high-voltage supply input terminal and the high-voltage startup transistor in the first semiconductor chip. The first and the second on-chip high-voltage resistors are configured to provide a voltage and a current related to a voltage at the high-voltage supply input terminal.