Abstract: A motor driver having a motor abnormality detection mechanism is provided. A motor position detecting circuit detects a change in a state of a rotor of the motor switching between a plurality of magnetic pole positions to output a commutation signal. An abnormality determining circuit, according the commutation signal, determines a plurality of time intervals during which the rotor of the motor is switched to the plurality of magnetic pole positions respectively to output an abnormality detected signal. A rotational protection controller circuit outputs a rotation protecting signal to a motor driving circuit according to the abnormality detected signal. A motor driving circuit drives the motor according to the rotation protecting signal. When the abnormality detected signal received by the rotational protection controller circuit indicates that the motor abnormally rotates, the rotational protection controller circuit adjusts the rotation protecting signal outputted to the motor driving circuit.

Abstract: A motor driver using a motor magnetic pole reference controlling mechanism is provided. A motor position detecting circuit detects a rotor of a motor to determine a plurality of magnetic pole positions to which the rotor of the motor is switched respectively during a plurality of time intervals. A reference magnetic pole switching circuit selects one of the plurality of time intervals according to a change in rotational speed of the motor over time. The reference magnetic pole switching circuit uses the magnetic pole position to which the rotor of the motor is switched during the one of the plurality of time intervals as magnetic pole reference data. A motor driving circuit drives the motor according to the magnetic pole reference data from the reference magnetic pole switching circuit.

Abstract: A motor driver having a motor abnormality detection mechanism is provided. A motor position detecting circuit detects a change in a state of a rotor of the motor switching between a plurality of magnetic pole positions to output a commutation signal. An abnormality determining circuit, according the commutation signal, determines a plurality of time intervals during which the rotor of the motor is switched to the plurality of magnetic pole positions respectively to output an abnormality detected signal. A rotational protection controller circuit outputs a rotation protecting signal to a motor driving circuit according to the abnormality detected signal. A motor driving circuit drives the motor according to the rotation protecting signal. When the abnormality detected signal received by the rotational protection controller circuit indicates that the motor abnormally rotates, the rotational protection controller circuit adjusts the rotation protecting signal outputted to the motor driving circuit.

Abstract: A motor driver using a motor magnetic pole reference controlling mechanism is provided. A motor position detecting circuit detects a rotor of a motor to determine a plurality of magnetic pole positions to which the rotor of the motor is switched respectively during a plurality of time intervals. A reference magnetic pole switching circuit selects one of the plurality of time intervals according to a change in rotational speed of the motor over time. The reference magnetic pole switching circuit uses the magnetic pole position to which the rotor of the motor is switched during the one of the plurality of time intervals as magnetic pole reference data. A motor driving circuit drives the motor according to the magnetic pole reference data from the reference magnetic pole switching circuit.

Abstract: An overvoltage protecting system and method of a motor pre-driver are provided. An overvoltage protecting circuit compares a first reference voltage with a common voltage inputted to a single phase motor to output a first comparison signal. When a controller circuit determines that the common voltage is higher than the first reference voltage according to the first comparison signal, the controller circuit turns off a first high-side switch and a second high-side switch, and turns on the first low-side switch and the second low-side switch, during a phase time of a phase transition signal of the single phase motor. After the phase time ends, the controller circuit alternately turns on the first low-side switch and the second low-side switch according to a level of the phase transition signal.

Abstract: A brake control system of a motor is provided. When a control circuit intends to brake the motor, the control circuit controls a driver circuit to turn off a first high-side switch and a second high-side switch, and to fully turn on the first low-side switch and the second low-side switch, for a period of time. Then, the control circuit controls the driver circuit to turn off one of the first low-side switch and the second low-side switch, and to continually turn on the other one of the first low-side switch and the second low-side switch, for a period of time. Then, the control circuit controls the driver circuit to turn off the other one of the first low-side switch and the second low-side switch, and to turn on the one of the first low-side switch and the second low-side switch, for a period of time.

Abstract: A brake control system of a motor is provided. When a control circuit intends to brake the motor, the control circuit controls a driver circuit to turn off a first high-side switch and a second high-side switch, and to fully turn on the first low-side switch and the second low-side switch, for a period of time. Then, the control circuit controls the driver circuit to turn off one of the first low-side switch and the second low-side switch, and to continually turn on the other one of the first low-side switch and the second low-side switch, for a period of time. Then, the control circuit controls the driver circuit to turn off the other one of the first low-side switch and the second low-side switch, and to turn on the one of the first low-side switch and the second low-side switch, for a period of time.

Abstract: A current limit protecting system and method of a motor pre-driver are provided. A current limiting circuit detects a current of a resistor that is connected to a motor, and then compares the current of the resistor with a current threshold to output a current comparing signal. When a controller circuit determines that the current of the resistor is larger than the current threshold according to the current comparing signal, and a working period of a first signal of a first node or a working period of a second signal of a second node of the motor reaches a preset value, a first high-side switch and a second high-side switch are turned off, and a first low-side switch and a second low-side switch are alternately turned on. As a result, a temperature of the motor generally reduces.

Abstract: A current limit protecting system and method of a motor pre-driver are provided. A current limiting circuit detects a current of a resistor that is connected to a motor, and then compares the current of the resistor with a current threshold to output a current comparing signal. When a controller circuit determines that the current of the resistor is larger than the current threshold according to the current comparing signal, and a working period of a first signal of a first node or a working period of a second signal of a second node of the motor reaches a preset value, a first high-side switch and a second high-side switch are turned off, and a first low-side switch and a second low-side switch are alternately turned on. As a result, a temperature of the motor generally reduces.

Abstract: An overvoltage protecting system and method of a motor pre-driver are provided. An overvoltage protecting circuit compares a first reference voltage with a common voltage inputted to a single phase motor to output a first comparison signal. When a controller circuit determines that the common voltage is higher than the first reference voltage according to the first comparison signal, the controller circuit turns off a first high-side switch and a second high-side switch, and turns on the first low-side switch and the second low-side switch, during a phase time of a phase transition signal of the single phase motor. After the phase time ends, the controller circuit alternately turns on the first low-side switch and the second low-side switch according to a level of the phase transition signal.

Abstract: A method for adjusting rotational speed of a motor is also disclosed. The method includes determining whether an input voltage of the motor enters into a predetermined voltage range; generating a pulse width modulation signal when the input voltage of the motor enters into the predetermined voltage range; and driving the motor to rotate according to the pulse width modulation signal.

Abstract: A method for adjusting rotational speed of a motor is also disclosed. The method includes determining whether an input voltage of the motor enters into a predetermined voltage range; generating a pulse width modulation signal when the input voltage of the motor enters into the predetermined voltage range; and driving the motor to rotate according to the pulse width modulation signal.

Abstract: An output buffer circuit with enhanced slew rate is disclosed. A first and a second slew-rate enhancing transistor are configured to enhance the slew rate of the source transistor and the sink transistor of an output stage. A first control circuit and a second control circuit turn off the first and the second slew-rate enhancing transistors during the static state, and turn on the first and the second slew-rate enhancing transistors during the transition.

Abstract: An output buffer circuit with enhanced slew rate is disclosed. A first and a second slew-rate enhancing transistor are configured to enhance the slew rate of the source transistor and the sink transistor of an output stage. A first control circuit and a second control circuit turn off the first and the second slew-rate enhancing transistors during the static state, and turn on the first and the second slew-rate enhancing transistors during the transition.