Patent ID: 8106611

Claim:
A switching regulation circuit for a dual-winding motor apparatus, the dual-winding motor apparatus comprising a first winding, a second winding and a supply rail, the first winding and the second winding being wound in adverse directions at a same position of the dual-winding motor apparatus, and alternately conducting a current, the dual-winding motor apparatus generating an induced voltage signal that represents an induced voltage of the second winding when the second winding has not yet conducted a current, the switching regulation circuit comprising: a gate-controlled device, having a gate, a drain and a source, the drain being coupled to the second winding, and the source being coupled to a ground end of the supply rail; and a driving circuit, comprising a negative-voltage comparator, the driving circuit being coupled to the gate and configured to detect the dual-winding motor apparatus with a rotational position of a rotor thereof to generate a detection signal, the negative-voltage comparator being configured to compare the induced voltage signal with a threshold value having a zero voltage level; wherein when the gate-controlled device has been turned off by the driving circuit in response to the detection signal, the negative-voltage comparator generates an output signal to turn on the gate-controlled device while the induced voltage signal is smaller than the zero voltage level.