A motor unit comprises a motor controller, a motor, and a Hall sensor, where the motor controller is used for driving the motor. The motor controller comprises a switch circuit, a control unit, a phase signal generating unit, and an operational amplifier. The control unit generates a plurality of control signals to control the switch circuit. The motor comprises a rotor, a silicon steel plate, and a coil. To increase a success rate of starting a forward rotation, the silicon steel plate may have an asymmetrical structure, such that a fan blade is inclined to a forward rotation direction in a still state. When a Hall voltage is zero, the motor controller may start the motor and switch phases.

A single-strand EC motor with a winding strand with two winding connections, has a current regulating device in the winding strands between the winding connections. The current regulating device regulates the winding current of the single-strand EC motor during a first commutation phase with a positive current flow and a second commutation phase with a negative current flow. In each case, at a constant value. The value of the average output voltage uw(t) of the current regulator is used to ascertain the commutation time.

A single-strand EC motor with a winding strand with two winding connections, has a current regulating device in the winding strands between the winding connections. The current regulating device regulates the winding current of the single-strand EC motor during a first commutation phase with a positive current flow and a second commutation phase with a negative current flow. In each case, at a constant value. The value of the average output voltage uw(t) of the current regulator is used to ascertain the commutation time.

A motor control apparatus operable to control a motor includes a phase determiner for determining a rotational phase of a rotor of the motor, and a controller having a first control mode for controlling a driving current flowing through a winding of the motor based on a current of a predetermined magnitude, and a second control mode for controlling a driving current flowing through the winding so that a deviation between a command phase representing a target phase of the rotor and a rotational phase determined by the phase determiner is reduced. The controller executes the first control mode without executing the second control mode in a case of rotating the motor in a first direction, and executes the second control mode in a case of rotating the motor in a second direction which is a reverse direction to the first direction.

A motor control apparatus operable to control a motor includes a phase determiner for determining a rotational phase of a rotor of the motor, and a controller having a first control mode for controlling a driving current flowing through a winding of the motor based on a current of a predetermined magnitude, and a second control mode for controlling a driving current flowing through the winding so that a deviation between a command phase representing a target phase of the rotor and a rotational phase determined by the phase determiner is reduced. The controller executes the first control mode without executing the second control mode in a case of rotating the motor in a first direction, and executes the second control mode in a case of rotating the motor in a second direction which is a reverse direction to the first direction.

A laser projection apparatus includes a main control circuit, a diffusion wheel driving circuit and a temperature sensor. The temperature sensor is electrically connected to the main control circuit, and configured to detect an ambient temperature. The main control circuit is configured to: determine a target starting current according to the ambient temperature; determine a duty cycle of a second startup pulse width modulation signal according to the target starting current, and provide the second startup pulse width modulation signal to the diffusion wheel driving circuit; and output an operating pulse width modulation signal to the diffusion wheel driving circuit when the diffusion wheel reaches a target rotation speed. The target starting current is a minimum drive current required to drive the motor from standstill to starting to rotate. The target rotation speed is a preset speed at which the diffusion wheel operates normally and speckles are eliminated.

A semiconductor device has an A/D converter configured to convert an analog signal representing a current flowing in a control target into a digital signal, an overcurrent determination unit configured to, based on the analog signal, determine that an overcurrent has occurred in the control target when the current flowing in the control target has exceeded an overcurrent threshold, and determine that the overcurrent has not occurred in the control target when the current flowing in the control target has not exceeded the overcurrent threshold, a drive control signal generation unit configured to generate a drive control signal for controlling driving of the control target so that the current flowing in the control target is equal to a target current, based on a conversion result of the A/D converter, and generate the drive control signal to reduce the current flowing in the control target when the overcurrent determination unit determines that the overcurrent has occurred, and an overcurrent threshold setting unit configured to set the overcurrent threshold based on the conversion result of the A/D converter and the target current.

Disclosed is a motor control apparatus including an inverter part configured to convert DC power into AC power and provide the AC power to a motor, and a controller configured to control driving of the motor by using the inverter part, the controller configured to identify a stop position of a rotor in previous driving of the motor, and control the inverter part to apply an input signal of a specific pattern to the motor according to a start of driving the motor, wherein a phase of the input signal of the specific pattern is determined on the basis of the stop position of the rotor. Other example embodiments may be provided.

Disclosed is a motor control apparatus including an inverter part configured to convert DC power into AC power and provide the AC power to a motor, and a controller configured to control driving of the motor by using the inverter part, the controller configured to identify a stop position of a rotor in previous driving of the motor, and control the inverter part to apply an input signal of a specific pattern to the motor according to a start of driving the motor, wherein a phase of the input signal of the specific pattern is determined on the basis of the stop position of the rotor. Other example embodiments may be provided.

A BLDC motor driver circuit includes: a driving power stage circuit configured to provide a start-up test signal in a start-up mode to excite a BLDC motor, to drive a rotor of the BLDC motor to rotate for a test; a current unidirectional circuit coupled to the BLDC motor at a reverse end for detecting a BEMF, to generate a detection signal at a forward end of the current unidirectional circuit, wherein when a voltage at the reverse end exceeds a voltage at the forward end, the current unidirectional circuit limits the voltage at the forward end not to be higher than a clamp voltage; a biasing circuit for biasing the current unidirectional circuit in a forward operation state and for providing the clamp voltage; and a sensor circuit for generating a sensing signal according to the detection signal to indicate a test rotation state of the BLDC motor.