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. 17, 2007
Filed:
Jul. 15, 2005
Chu Yu Chu, Taipei County, TW;
You Min Sun, Taipei County, TW;
Mao Cyuan Jian, Taipei County, TW;
Shih Jie Liao, Taipei, TW;
Chu Yu Chu, Taipei County, TW;
You Min Sun, Taipei County, TW;
Mao Cyuan Jian, Taipei County, TW;
Shih Jie Liao, Taipei, TW;
Advanced Analog Technology, Inc., Hsinchu, TW;
Abstract
The present invention discloses a DC-to-DC step-up converter to which a logic control unit is added in order to reduce the ripples of a DC output voltage and improve the power quality. The converter of the present invention comprises a step-up circuit, a ring oscillator, a divider circuit, a PFM (pulse frequency modulation) comparator and a logic control unit. The step-up circuit is used to step up a source voltage to generate a DC output voltage. The ring oscillator is used to generate an oscillator output signal. The divider circuit receives the DC output voltage to generate a feedback voltage. The PFM comparator compares the feedback voltage with a reference voltage to generate a comparator output signal to control outputting of the oscillator output signal. The logic control unit is used to make the conductive period of a MOS transistor in the step-up circuit identical to the high-level period of an output signal of the ring oscillator to reduce the noise and the ripple of the DC output voltage of the converter.