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:
Jan. 26, 2016
Filed:
Mar. 24, 2014
Texas Instruments Incorporated, Dallas, TX (US);
Anuj Jain, Irving, TX (US);
Mario Marascutti, Fontanafredda, IT;
Wenchao Qu, Dallas, TX (US);
Michael Edwin Butenhoff, Minnesota City, MN (US);
TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US);
Abstract
Stepper motor winding current regulation methods and apparatus continuously and bi-directionally sense winding current to determine both the magnitude of the winding current and the slope of a waveform representing the winding current. The magnitude and slope information is used to more precisely control periods of current rise and characteristics of fast and slow current decay during pulse-width modulation ('PWM') regulation cycles. Winding current rise and decay shaping is based upon the sensed magnitude of the winding current, the magnitude of the winding current regulation set-point ITRIP, whether the sensed winding current is greater than or less than ITRIP at a selected sampling time, whether the sensed winding current is increasing or decreasing when a waveform of the sensed winding current crosses over ITRIP, and whether or not the magnitude of ITRIP changes during a PWM cycle in response to a receipt of a subsequent DAC code.