Patent ID: 7412156
Filing Date: 2008-08-12
Classification: H02P,Y10S

Abstract:
1. A brushless dc motor driver circuit capable of reducing vibration or shock noise, comprising: a brushless dc motor; at least one magnetic field detecting circuit, detecting a periodically varying magnetic field of said brushless dc motor and then outputting a detected signal; at least one counter, connected to said magnetic field detecting circuits and used to calculate a time interval of a rising signal and a time interval of a falling signal during the magnetic field variation of said brushless dc motor via said magnetic field detecting circuits; a signal processor, connected to said counters, dividing the time interval of said rising signal and the time interval of said falling signal into a plurality of time segments respectively, generating and outputting a corresponding linearly rising signal and a corresponding linearly falling signal according to said detected signal; and a driver circuit, connected to said signal processor and said brushless dc motor, receiving said linearly falling signal and said linearly rising signal, and utilizing said linearly falling signal and said linearly rising signal to drive said brushless dc motor.