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:
Feb. 07, 2017
Filed:
Dec. 19, 2014
Sanken Electric Co., Ltd., Niiza-Shi, Saitama, JP;
Akira Hayakawa, Niiza, JP;
Masaaki Shimada, Niiza, JP;
SANKEN ELECTRIC CO., LTD., Niiza-shi, JP;
Abstract
Disclosed is a switching power-supply device that induces a pulse voltage in a secondary winding of the transformer, and outputs, to a load, an output voltage rectified and smoothened by a secondary-side rectification smoothing circuit including a rectifier diode and a smoothing capacitor. An input-voltage detection circuit detects the input voltage of the alternating-current power supply. An error amplifier compares the output voltage with a reference voltage, and transmits a resultant error voltage to a primary side as a feedback signal. An internal oscillation circuit selects any of frequency decrease settings according to the input voltage detected by the input-voltage detection circuit, and performs, by using the selected frequency decrease setting, a frequency decreasing function of decreasing a switching frequency of the switching element at a light load, in response to the feedback signal transmitted from a secondary side to inform a state of the load.