Stephen C Sanchez

US Patent:

20130342145, Dec 26, 2013

Filed:

Mar 15, 2013

Appl. No.:

13/835101

Inventors:

Jason William Lawrence - Austin TX, US
Stephen James Sanchez - Tucson AZ, US
John L. Melanson - Austin TX, US
Miroslav Oljaca - Tucson AZ, US

Assignee:

Cirrus Logic, Inc. - Austin TX

International Classification:

H02P 6/18

US Classification:

31840033

Abstract:

The system and method disclose for the controlling of sequential phase switching in driving a set of stator windings of a multi-phase sensorless brushless permanent magnet DC motor. A motor controller controls a power stage that drives two windings of a set of three windings in the motor with pulse width modulated signal. A plurality of voltage values on an undriven winding of the set of three windings are sampled within a window of time, wherein a period beginning when the driven windings are energized and ending when the driven windings are de-energized encompasses the window of time. The sampled voltage values are processed. When the processed voltage values exceed a threshold, the motor controller changes which two windings are driven.