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:
Apr. 19, 2016
Filed:
Sep. 08, 2011
Daisuke Aoki, Aichi-ken, JP;
Tsutomu Murata, Mizuho, JP;
Daisuke Aoki, Aichi-ken, JP;
Tsutomu Murata, Mizuho, JP;
SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC, Phoenix, AZ (US);
Abstract
A drive signal generating unit generates a drive signal having a cyclic waveform containing a zero period in a vibration mode. A driver unit generates the drive current in response to the drive signal generated by the drive signal generating unit so as to supply the drive current to a voice coil. An induced voltage detector detects the induced voltage occurring in the voice coil during a nonconducting period. A zero-cross detector detects the zero cross of the induced voltage detected by the induced voltage detector. The drive signal generating unit estimates the eigen-frequency of a vibration speaker from a detected position of the zero cross and brings the frequency of the drive signal close to the estimated eigen-frequency.