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:
Jan. 31, 2012
Filed:
May. 21, 2009
Yoshiyuki Hojo, Kyoto, JP;
Hirotaka Nakabayashi, Kyoto, JP;
Yoshiyuki Hojo, Kyoto, JP;
Hirotaka Nakabayashi, Kyoto, JP;
Rohm Co., Ltd., Kyoto-shi, Kyoto-fu, JP;
Abstract
A switching power supply includes a switching element connected to a power supply voltage and performs ON and OFF operation; a control circuit; a coil; a capacitor connected to the coil and performs a rectifying operation with the coil; an oscillator to output an oscillator signal to the control circuit; a first comparator for comparing a current detection voltage which transforms a detection current flowing through the coil into a voltage, and the feedback voltage according to a difference of a voltage according to an output voltage with a reference voltage; and a second comparator for comparing a deep threshold voltage set as a value higher than the current detection voltage and is lower than the power supply voltage, with the feedback voltage. A Deep Simple Light Load Mode control is introduced to improve efficiency in a light or no-load area in addition to PWM mode in a heavy loading.