Motor controller
AssigneeGlobal Mixed-mode Technology Inc.
InventorChing-Feng Lai
Life of this patent
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Abstract
A motor controller configured to reduce the motor noise by detecting the zero point of the motor current is disclosed. The motor controller comprises a switch circuit, a pre-driver, a phase detecting unit, a control unit, a comparator, a first resistor, and a second resistor. The switch circuit is an H-bridge circuit. The switch circuit includes a first upper-side switch, a second upper-side switch, a first lower-side switch, and a second lower-side switch. When the motor controller performs the last pulse width modulation driving with respect to the first lower-side switch before phase switching, the second upper-side switch is turned off and the first lower-side switch is kept turning on, so as to facilitate the detection of the zero point of the motor current.
Claims4
A motor controller configured to drive a motor, wherein the motor has a motor coil, the motor coil has a first terminal and a second terminal, and the motor controller comprises:
- a switch circuit, configured to supply a motor current to the motor coil, wherein the switch circuit comprises a first upper-side switch, a second upper-side switch, a first lower-side switch, and a second lower-side switch, the first upper switch is coupled to a third terminal and the first terminal, the first lower-side switch is coupled to the first terminal and a fourth terminal, the second upper-side switch is coupled to the third terminal and the second terminal, and the second lower-side switch is coupled to the second terminal and the fourth terminal;
- a pre-driver, configured to generate a plurality of driving signals to control the switch circuit;
- a control unit, configured to generate a control signal to the pre-driver;
- a phase detecting unit, configured to generate a phase signal to the control unit;
- a first resistor, coupled to the fourth terminal and a fifth terminal;
- and
- a comparator, coupled to the first terminal and the fourth terminal for generating a detecting signal to the control unit, wherein when the motor controller performs a last pulse width modulation driving with respect to the first lower-side switch before phase switching, the second upper-side switch is turned off and the first lower-side switch is kept turning on.
Dependencies are inferred from the claim text.