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:
Mar. 31, 2009
Filed:
Mar. 06, 2007
Manabu Oyama, Kyoto, JP;
Daisuke Uchimoto, Kyoto, JP;
Manabu Oyama, Kyoto, JP;
Daisuke Uchimoto, Kyoto, JP;
Rohm Co., Ltd., , JP;
Abstract
A switching power supply apparatus generates a first output voltage with a reversed polarity of an input voltage and a second input voltage of double the input voltage with the reversed polarity, and then outputs them from the first output terminal and the second output terminal. A driver circuit includes a control unit and a first switch to a sixth switch. The driver circuit repeats three charging periods in a time-division manner. The three charging periods are a first charging period during which a flying capacitor is charged with the input voltage, a second charging period in which a low-potential-side terminal of the flying capacitor is connected to a ground terminal and a first output capacitor is charged with a voltage appearing at the other end of the flying capacitor, and a third charging period in which a high-potential-side of the flying capacitor is connected with the first output terminal and a second output capacitor is charged with a voltage appearing at the other end of the flying capacitor.