Driving circuit for stepping motor
US8416664B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2012 |
| Grant date | Apr 9, 2013 |
| Priority date | — |
| Expiry date | Sep 28, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08582
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A stepping-motor-driving circuit for an optical pickup: includes a control-signal-generating circuit to generate a plurality of control signals for supplying driving currents to driving coils having a plurality of phases during energized periods, with a de-energized period therebetween; a plurality of output circuits to supply the currents to the respective coils, in response to the signals; an induced-voltage-detecting circuit to compare a voltage generated each in the coils with a threshold voltage during the de-energized period; a threshold-voltage-setting circuit; and a determining circuit to determine whether a collision state is present where the pickup reaches an end of a movement range, based on an induced-voltage-detecting-circuit-detection result, the threshold voltage set at a voltage between a voltage generated each in the coils during the de-energized period when the stepping motor stops or rotates in the state, and a voltage generated therein in the de-energized period when no collision state is present.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.