Drive circuit and method
AssigneeSemiconductor Components Industries, LLC
InventorKosaku Hioki
Life of this patent
Estimating the term…
Abstract
A stepping motor includes two coils. A driver circuit drives the stepping motor by setting dissimilar phases of supply currents to these two coils. One terminal of one coil is connected to ground and another terminal is set to a high impedance state, and an induced voltage generated at that coil is detected as a voltage with respect to ground. Then, in accordance with the state of the detected induced voltage, the magnitude of motor drive current supplied to the two coils is controlled.
Claims24
A method for controlling a motor, comprising:
- generating a drive control signal in response to an input signal;
- generating a first output signal in response to the drive control signal, wherein the first output signal has a voltage component and a current component;
- generating an adjustment signal in response to the voltage component of the first output signal;
- and
- generating an adjusted drive control signal in response to the input signal and the adjustment signal.
A method for adjusting a drive current of a motor driver, comprising:
- generating an adjustment signal in response to the amplitude of the drive current;
- generating a drive control signal in response to the adjustment signal;
- and
- generating an adjusted drive current in response to the drive control signal.
A driver circuit suitable for driving a motor, comprising:
- an output control circuit having first and second inputs and an output;
- an output circuit having first and second inputs and a plurality of outputs, the first input of the output circuit coupled to the output of the output control circuit;
- an adjustment circuit having a plurality of inputs and first and second outputs, the first output coupled to the second input of the output control circuit and the second output coupled to the second input of the output circuit, wherein the adjustment circuit generates an adjustment signal at its first output in response to at least one input signal appearing at a first input of the plurality of inputs.
The driver circuit of 19, wherein the adjustment circuit comprises a timing circuit having an input coupled to the output control circuit and an output coupled to the output circuit.
Dependencies are inferred from the claim text.