Patent ID: 7323839

Claim:
A controlling method for a direct current motor, comprising: getting a duty signal by a microprocessor unit and then transforming the duty signal to computed value by a function; producing a duty level after computing the computed value by a microprocessor from executing a dichotomy method, after producing said duty level, said microprocessor unit producing a target value by executing a rotation method and a transformed function; according to said target value, said microprocessor unit providing a frequency signal to a driving circuit unit, according to said frequency signal received from said microprocessor unit, providing a driving voltage to a power switch by said driving circuit unit; according to said driving voltage, said switch power providing a voltage to said direct current motor or not in order to controlling output performance of said direct current motor; providing a status signal after detecting said direct current motor by a direct current motor voltage detecting unit; transforming said status signal received from said direct current motor voltage detecting unit to a compared signal and then providing said compared signal to said microprocessor unit by a direct current motor voltage feedback unit; and while said compared signal received from said direct current motor voltage feedback unit, comparing said compared signal to said target value for modifying said frequency signal and then sending said modified frequency signal to said driving circuit unit by said microprocessor unit.