Invention Grant
- Patent Title: Electronic watch
- Patent Title (中): 电子手表
-
Application No.: US13578929Application Date: 2011-02-09
-
Publication No.: US08848492B2Publication Date: 2014-09-30
- Inventor: Masaaki Namekawa , Yu Takyo
- Applicant: Masaaki Namekawa , Yu Takyo
- Applicant Address: JP Tokyo JP Tokyo
- Assignee: Citizen Holdings Co., Ltd.,Citizen Watch Co., Ltd
- Current Assignee: Citizen Holdings Co., Ltd.,Citizen Watch Co., Ltd
- Current Assignee Address: JP Tokyo JP Tokyo
- Agency: Sughrue Mion, PLLC
- Priority: JP2010-029909 20100215
- International Application: PCT/JP2011/052786 WO 20110209
- International Announcement: WO2011/099536 WO 20110818
- Main IPC: H02P8/00
- IPC: H02P8/00 ; G04C3/14 ; G04G19/10 ; H02P8/02

Abstract:
When recovering power from a motor driver, a forward voltage across a parasitic diode can reduce the recovery efficiency, and control of a power recovery operation can take an unnecessarily long time. In order to address this problem, the power recovery operation is performed as follows without being affected by a parasitic diode: near a peak position of a waveform of an induced current resulting from free oscillation of a rotor after a drive pulse is output, a recovery pulse having such a level that the rotor does not rotate is output from a terminal different from a motor driver terminal to which the drive pulse was output. Also, by adjusting the width and output timing of the recovery pulse based on a power supply voltage, the power recovery can be optimized for the power supply voltage.
Public/Granted literature
- US20120307602A1 ELECTRONIC WATCH Public/Granted day:2012-12-06
Information query