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. 29, 2000
Filed:
Jan. 20, 1999
Seiki Igarashi, Kawasaki, JP;
Akio Suzuki, Kawasaki, JP;
Fuji Electric Co., Ltd., Kawasaki, JP;
Abstract
A switching power supply for outputting an isolated DC voltage includes a transformer TR1 having a secondary winding N21 and a tertiary winding N3; a semiconductor switch Q1; a DC voltage source (capacitor) C1 connected to the transformer TR1 and the semiconductor switch Q1; a rectifier D1 connected to the secondary winding N21; a power IC, the power supply voltage for which is obtained by rectifying the output of the tertiary winding N3 of the transformer TR1; and a comparator IC5 for detecting the voltage of the control power supply that is lower than a predetermined value, by which to shift to the power saving mode of operation. The above configuration eliminates the photo-coupler for transmitting the power saving signal and reduces the number of terminals of the power IC.