Abstract: A step-down switching regulator includes a switching device coupled to an input terminal to which an input voltage is applied, an inductor having a first end and a second end, the first end being connected to the switching device, a smoothing unit having an output terminal and configured to smooth a voltage at the second end of the inductor and generate an output voltage at the output terminal, a rectifier configured to flow a current to the inductor when the switching device is in an OFF state, and a control circuit configured to drive the switching device so that the output voltage becomes equal to a set target voltage. The control circuit detects a difference voltage between the input voltage and the output voltage or a difference voltage between the input voltage and the set target voltage, and causes the switching device to be in an ON state when the difference voltage is lower than or equal to a predetermined voltage value.

Abstract: A step-down switching regulator includes a switching device coupled to an input terminal to which an input voltage is applied, an inductor having a first end and a second end, the first end being connected to the switching device, a smoothing unit having an output terminal and configured to smooth a voltage at the second end of the inductor and generate an output voltage at the output terminal, a rectifier configured to flow a current to the inductor when the switching device is in an OFF state, and a control circuit configured to drive the switching device so that the output voltage becomes equal to a set target voltage. The control circuit detects a difference voltage between the input voltage and the output voltage or a difference voltage between the input voltage and the set target voltage, and causes the switching device to be in an ON state when the difference voltage is lower than or equal to a predetermined voltage value.

Abstract: A motor driving apparatus includes a position detector for detecting a rotational position of a motor to output the detection result as a position signal, a frequency comparator for comparing frequencies of continuous periods in the position signal and detecting a reversed state in which the frequency of the signal in the later period is higher than the frequency of the signal in the earlier period, a brake change over unit for selecting a reverse torque brake control which applies reverse torque to the rotor for braking or a short brake control which shorts coils of the motor for braking and instructing the brake control. The brake change over unit changes over the brake control from the reverse torque brake control to the short brake control, when a command signal for applying a reverse torque is output and the frequency comparator detects the reversed state.

Abstract: A position detection section 10 outputs a position signal 101 indicating the relative position between motor windings L1 to L3 and a rotor 60. A crossing detection section 20a outputs a rotation signal 241 indicating the magnitude relation between the position signal 101 and a reference signal 102. An energization control signal generation section 30 generates, based on the rotation signal 241, energization control signals 301 for the motor windings L1 to L3. An edge signal 221 is outputted when the magnitude relation of the two signals is reversed, and a mask signal 231 is outputted over a predetermined period of time from when the edge signal 221 is outputted. While the mask signal 231 is being outputted, the crossing detection section 20a continuously outputs, as the rotation signal 241, a comparison result signal 211 which had been inputted before the mask signal 231 was outputted.

Abstract: A position detection section 10 outputs a position signal 101 indicating the relative position between motor windings L1 to L3 and a rotor 60. A crossing detection section 20a outputs a rotation signal 241 indicating the magnitude relation between the position signal 101 and a reference signal 102. An energization control signal generation section 30 generates, based on the rotation signal 241, energization control signals 301 for the motor windings L1 to L3. An edge signal 221 is outputted when the magnitude relation of the two signals is reversed, and a mask signal 231 is outputted over a predetermined period of time from when the edge signal 221 is outputted. While the mask signal 231 is being outputted, the crossing detection section 20a continuously outputs, as the rotation signal 241, a comparison result signal 211 which had been inputted before the mask signal 231 was outputted.

Abstract: A motor driving apparatus includes a position detector for detecting a rotational position of a motor to output the detection result as a position signal, a frequency comparator for comparing frequencies of continuous periods in the position signal and detecting a reversed state in which the frequency of the signal in the later period is higher than the frequency of the signal in the earlier period, a brake change over unit for selecting a reverse torque brake control which applies reverse torque to the rotor for braking or a short brake control which shorts coils of the motor for braking and instructing the brake control. The brake change over unit changes over the brake control from the reverse torque brake control to the short brake control, when a command signal for applying a reverse torque is output and the frequency comparator detects the reversed state.

Abstract: Brake mode switching signal production means detects the number of revolutions per unit time of a rotor according to a change in a positional relationship between motor windings of a plurality of phases and the rotor so as to output first and second brake mode switching signals for selecting either a short brake mode or a reverse brake mode for braking the rotation of the rotor based on the number of revolutions. Control means outputs an energization control signal for controlling energization of the motor windings of a plurality of phases in response to the first and second brake mode switching signals. Thus, it is possible to reduce the braking noise and the stopping time.

Abstract: Brake mode switching signal production means detects the number of revolutions per unit time of a rotor according to a change in a positional relationship between motor windings of a plurality of phases and the rotor so as to output first and second brake mode switching signals for selecting either a short brake mode or a reverse brake mode for braking the rotation of the rotor based on the number of revolutions. Control means outputs an energization control signal for controlling energization of the motor windings of a plurality of phases in response to the first and second brake mode switching signals. Thus, it is possible to reduce the braking noise and the stopping time.