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:
Aug. 03, 1999
Filed:
Apr. 28, 1998
Steven F Liepe, Ft. Collins, CO (US);
Tessa H Velasquez, Loveland, CO (US);
Kenneth G Richardson, Ft. Collins, CO (US);
Hewlett-Packard Co., Palo Alto, CA (US);
Abstract
A switching power supply that uses the intrinsic series resistance of an output bypass capacitor to sense changes in current flow through a switch that is connects between the input and output of the switching power supply. When the switch runs on, current flows from the input to the output and through a bypass capacitor. The intrinsic series resistance of the bypass capacitor develops a voltage across it as current flows through the capacitor. This voltage is used by a sense circuit to help determine when to shut off the switch. A low-cost regulator develops an output voltage that is divided and compared to a reference to determine if the input voltage is sufficient. If it is not, the power supply is not allowed to operate and the switch is not allowed to turn on.