Switching regulation circuit and dual-winding motor apparatus
A switching regulation circuit for a dual-winding motor apparatus is provided. The switching regulation circuit comprises a gate-controlled device and a driving circuit. When one of the two windings generates an induced voltage signal greater than a threshold value, the driving circuit generates an output signal for turning on the gate-controlled transistor. Thereby, a parasitic diode of the gate-controlled device will not be turned on and damage the entire circuit.
1. 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.
2. The switching regulation circuit as claimed in claim 1 , wherein the gate-controlled device is a N-type metal-oxide-semiconductor field transistor (N-type MOSFET).
3. The switching regulation circuit as claimed in claim 1 , wherein the driving circuit further comprises a rotation detector being configured to detect the rotational position of the rotor of the dual-winding motor apparatus for generating the detection signal.
4. The switching regulation circuit as claimed in claim 3 , wherein the rotation detector is a magnetic field detector being configured to detect a variation of magnetic field caused by rotation of the rotor of the dual-winding motor apparatus to generate the detection signal.
5. A dual-winding motor apparatus, comprising:
a rotor and a stator, in which the rotor rotates relatively to the stator;
a first winding and a second winding being wound in adverse directions at a same position of the dual-winding motor apparatus, and alternatively conducting a current, the second winding generating an induced voltage signal when the first winding conducts current and the second winding has not yet conducted a current;
a supply rail;
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.
6. The dual-winding motor apparatus as claimed in claim 5 , wherein the gate-controlled device is a N-type metal-oxide-semiconductor field transistor (N-type MOSFET).
7. The dual-winding motor apparatus as claimed in claim 5 , wherein the driving circuit further comprises a rotation detector being configured to detect the rotational position of the rotor of the dual-winding motor apparatus for generating the detection signal.
8. The dual-winding motor apparatus as claimed in claim 7 , wherein the rotation detector is a magnetic field detector being configured to detect a variation of magnetic field to generate the detection signal when the rotor rotates.