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:
Mar. 18, 2003
Filed:
Mar. 30, 2001
STMicroelectronics S.r.l., Agrate Brianza, IT;
Abstract
A current control method controls current for drive systems of multi-phase brushless motors, in particular at phase switching, wherein the motor coils coupled to a common node are driven by applying a respective drive voltage to the free end of each coil via corresponding power stages. The method comprises switching the current flow from one phase to the next in the direction of rotation of the motor at the phase switch, thereby forcing the unaffected one of said coils by the phase switch into a state of high impedance. Advantageously, the decreasing rate of the current in the coil unaffected by the phase switch can be twice as high as the decreasing rate of the current in the phase being switched from.