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:
Jul. 14, 2015
Filed:
Dec. 03, 2012
Fujitsu Limited, Kawasaki-shi, Kanagawa, JP;
Hiroyuki Nakamoto, Kawasaki, JP;
FUJITSU LIMITED, Kawasaki, JP;
Abstract
A DC-DC converter includes: a step-up-or-step-down circuit including a choke coil and step-down and step-up transistor pairs; and a control circuit to control the transistor pairs based on an output voltage, wherein the control circuit includes: a differential triangular wave generation circuit to generate a positive-phase triangular wave signal and a negative-phase triangular wave signal; a switch to select the positive-phase triangular wave signal or the negative-phase triangular wave signal in response to a switching signal; an error detector to output an error signal; a PWM comparator to compare the positive-phase triangular wave signal or the negative-phase triangular wave signal with the error signal to generate a control pulse signal; a switching comparator to compare the error signal with reference potential and generate the switching signal; and a driver control circuit to generate a control signal for the transistor pairs based on the control pulse signal and the switching signal.