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. 24, 2007
Filed:
May. 10, 2006
Hidenori Takahashi, Saitama, JP;
Koichi Nagata, Saitama, JP;
Hidenori Takahashi, Saitama, JP;
Koichi Nagata, Saitama, JP;
Fujinon Corporation, Saitama-shi, JP;
Abstract
A motor drive circuit is provided and includes: a PWM wave generation circuit for generating a PWM (pulse-width-modulated) wave having a high frequency, whose pulse width has been modulated, in response to a rotational frequency control signal used for driving a motor; a switching element (FET) that receives an input of a PWM wave output from the PWM wave generation circuit and performs switching operation; and a current resonance circuit including an inductance and a capacitor. Current resonance is induced in response to power of a battery cell imparted by means of operation of the switching element. A value falling within the range of 60 to 90 KHz, which is 1.1 to 1.7 times as large as a switching frequency 54 KHz of the switching element, may be selected and set for the resonance frequency.