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:
May. 20, 2003
Filed:
Nov. 23, 2001
TDK Corporation, Tokyo, JP;
Abstract
A switching power supply unit capable of adjusting the inductance value of a resonance circuit and outputting a rated output voltage regardless of any fluctuation in an input voltage and a load. The switching power supply unit comprises first to fourth switching elements connected with each other in a bridge connection. A diode having a reverse polarity and a capacitor are disposed between main electrodes of each of the switching elements. A first winding of a transformer is connected between first and second connection points An inductor is inserted into a path ranging from the first connection point through the first winding to the second connection point and forms a resonance circuit in conjunction with the capacitors The inductance value L2 of the inductor is arranged to provide the output voltage Vout of an output circuit greater than or equal to the rated output voltage Vout (nom), in a minimum input voltage Vin (mm), a maximum output current Iout (max), and a switching phase-difference f of zero.