Patent ID: 8912744

Claim:
A method for dynamically adjusting a dead time of a brushless direct-current motor during a phase change, wherein the brushless direct-current motor is connected between two output terminals of an H-bridge circuit that is established by a first upper-side switch, a first lower-side switch, a second upper-side switch, and a second lower-side switch, the method comprising: A.) during the dead time, turning on the second lower-side switch while turning off the other switches, or turning on the first and the second lower-side switches while turning off the other switches, for consuming a winding current of the brushless direct-current motor; B.) detecting the winding current during the dead time; and C.) terminating the dead time once the winding current is detected equal to or smaller than a zero-current threshold; wherein the step B comprises temporarily turning off the second lower-side switch for the winding current to be detected.