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. 07, 2015
Filed:
Mar. 13, 2013
Cirrus Logic, Inc., Austin, TX (US);
Stephen James Sanchez, Tucson, AZ (US);
Marc John Kobayashi, Oro Valley, AZ (US);
Branislav Pjetar, Novi Sad, RS;
Cirrus Logic, Inc., Austin, TX (US);
Abstract
The system discloses structure for synchronizing sequential phase switching in driving a set of stator windings of a multi-phase sensorless brushless permanent magnet DC motor. A drive voltage drives a plurality of the stator windings thereby producing a magnetic field. On an undriven stator winding among the stator windings, a voltage induced by the magnetic field is sampled. The induced voltage changes as a function of a magnetic rotor transitioning across a plurality of angular positions. A first value corresponding to the sampled voltage induced on the currentless winding is compared with a commutation threshold to determine a proper commutation point. The system is switched to a next drive configuration of the sequence when the first value surpasses the threshold.