Abstract: In a drive control circuit of a linear vibration motor, a differential amplifier circuit includes an operational amplifier in which an P-channel type transistor is used as a transistor that receives an input voltage, and the differential amplifier circuit detects an induced voltage occurring in a coil. Before the H-bridge circuit is controlled to a high impedance state, a drive signal generating unit turns on a first transistor and a second transistor, and delivers a regenerative current through the coil, the first transistor, the second transistor and the power supply potential.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil. The drive signal is such that nonconducting periods are set before and after a positive current conducting period and the nonconducting periods are set before and after a negative current conducting period. A driver unit generates the drive current in response to the drive signal generated by the drive signal generating unit and then supplies the drive current to the coil. The drive signal generating unit sets the width of a nonconducting period such that, after the drive start of the linear vibration motor, the width of a nonconducting period to be set before at least the first conducting period of the drive signal is shorter than the width of a nonconducting period to be set before each conducting period during steady operation of the linear vibration motor.

Abstract: A drive control signal is effectively obtained. An offset is added to a rotational state signal. A drive control signal having a period which is reduced by a predetermined period compared to the sine wave form signal is generated between a crossing of a reference value for a second time and a crossing of the reference value for a next time by an added signal obtained by sequentially offsetting the rotational state signal in a direction reaching the reference value. A pulse indicating that the polarity has been reversed when the offset is added is added to the crossing of the reference value for the first time, to reliably detect crossing of the reference value for the second time.

Abstract: A PWM mode for turning on and off two output transistors by an output of a high impedance circuit and a constant voltage mode for controlling voltages at two output terminals by an output of an op amp are provided. Then, the two modes are switched by a switching signal.

Abstract: A driving circuit for a single-phase brushless motor includes: a driving-signal-generating circuit to generate a driving signal for supplying first and second driving currents to a driving coil of the single-phase brushless motor in an alternate manner with a de-energized period therebetween; an output circuit to supply the first or the second driving current to the driving coil in response to the driving signal; and a zero-cross detecting circuit to detect a zero cross of an induced voltage, generated across the driving coil, during the de-energized period, wherein the driving-signal-generating circuit determines a length of a subsequent energized period, based on a driving cycle from a start of an energized period to a time when the zero-cross detecting circuit detects the zero cross, and the zero-cross-detecting circuit starts detection of the zero-cross after a predetermined time period has elapsed from a start of the de-energized period.

Abstract: A PWM mode for turning on and off two output transistors by an output of a high impedance circuit and a constant voltage mode for controlling voltages at two output terminals by an output of an op amp are provided. Then, the two modes are switched by a switching signal.

Abstract: A driving circuit for a single-phase-brushless motor, includes: a driving-signal-generating circuit to generate a driving signal for supplying, to a driving coil of the single-phase-brushless motor, first- and second-driving currents, alternately with a de-energized period therebetween during which neither of the first or the second driving current is supplied to the driving coil; an output circuit to supply the first or the second driving current to the driving coil in response to the driving signal; and a zero-cross detecting circuit to detect a zero cross of an induced voltage, generated across the driving coil, during the de-energized period, wherein the driving-signal-generating circuit determines a length of a subsequent energized period based on a driving cycle from a start of an energized period, during which the output circuit supplies the first or the second driving current to the driving coil, to a time when the zero-cross-detecting circuit detects the zero cross.

Abstract: A driving circuit for a single-phase-brushless motor includes a driving-signal-generating circuit to generate a driving signal for supplying, to a driving coil of the single-phase-brushless motor, first- and second-driving currents alternately with a de-energized period therebetween, an output circuit, and a zero-cross-detecting circuit.

Abstract: A drive control signal is effectively obtained. An offset control circuit (32) adds an offset to a rotational state signal.

Abstract: PWM conversion is efficiently executed. An output control circuit comprises a flip-flop which reads crossing of a reference value by a rotational state signal from a motor, and generates a motor drive control signal according to a state of the flip-flop. A clock generator generates a clock which defines a time of reading data in the flip-flop of the output control circuit. A PWM conversion circuit PWM-converts the drive control signal using the clock as a PWM signal.

Abstract: A drive control signal is effectively obtained. An offset is added to a rotational state signal. A drive control signal having a period which is reduced by a predetermined period compared to the sine wave form signal is generated between a crossing of a reference value for a second time and a crossing of the reference value for a next time by an added signal obtained by sequentially offsetting the rotational state signal in a direction reaching the reference value. A pulse indicating that the polarity has been reversed when the offset is added is added to the crossing of the reference value for the first time, to reliably detect crossing of the reference value for the second time.

Abstract: A drive signal generating unit generates a drive signal having a cyclic waveform containing a zero period in a vibration mode. A driver unit generates the drive current in response to the drive signal generated by the drive signal generating unit so as to supply the drive current to a voice coil. An induced voltage detector detects the induced voltage occurring in the voice coil during a nonconducting period. A zero-cross detector detects the zero cross of the induced voltage detected by the induced voltage detector. The drive signal generating unit estimates the eigen-frequency of a vibration speaker from a detected position of the zero cross and brings the frequency of the drive signal close to the estimated eigen-frequency.

Abstract: In a drive control circuit of a linear vibration motor, the drive signal generating unit generates a drive signal whose phase is opposite to that of the drive signal generated during the motor running, after the running of the linear vibration motor has terminated; this drive signal of opposite phase includes a high impedance period during which the driver unit is controlled to a high impedance state. An induced voltage detector detects an induced voltage occurring in the coil. A comparator has a function as a hysteresis comparator in which the output level does not vary in a predetermined dead band, and the comparator outputs a high-level signal or a low-level signal during the high impedance period. When an in-phase signal is consecutively outputted from the comparator during the consecutive high-impedance periods, the drive signal generating unit determines that the linear vibration motor has come to a stop.

Abstract: In a drive control circuit of a linear vibration motor, a differential amplifier circuit includes an operational amplifier in which an P-channel type transistor is used as a transistor that receives an input voltage, and the differential amplifier circuit detects an induced voltage occurring in a coil. Before the H-bridge circuit is controlled to a high impedance state, a drive signal generating unit turns on a first transistor and a second transistor, and delivers a regenerative current through the coil, the first transistor, the second transistor and the power supply potential.

Abstract: In a drive control circuit of a linear vibration motor, a drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil. A driver unit generates a drive current in response to the drive signal generated by the drive signal generating unit and supplies the drive current to the coil. An induced voltage detector detects an induced voltage occurring in the coil. After a running of the linear vibration motor has terminated, the drive signal generating unit generates a drive signal whose phase is opposite to that of the drive signal generated during the motor running; this drive signal of opposite phase includes a high impedance period during which the driver unit is controlled to a high impedance state. The induced voltage detector detects the induced voltage occurring in the coil during the high impedance period.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil with a nonconducting period inserted between conducting periods. A driver unit generates a drive current in response to the drive signal generated by the drive signal generating unit and supplies the drive current to a coil. The drive signal generating unit estimates the eigen frequency of a linear vibration motor based on a detected position of the zero cross occurring in the coil during the nonconduting period, and the frequency of the drive signal is brought close to the estimated eigen frequency. The zero-cross detecting unit sets a detection window for avoiding the detection of zero cross of voltages other than the induced voltage. The zero-cross detecting unit enables a zero cross detected within the detection window and disables a zero cross detected outside the detection window.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil. A driver unit generates the drive current in response to the drive signal generated by the drive signal generating unit and supplies the drive current to the coil. After the drive termination of a linear vibration motor, the drive signal generating unit generates a drive signal whose phase is opposite to the phase of the drive signal generated during the motor running. The driver unit quickens the stop of the linear vibration motor by supplying to the coil the drive current of opposite phase according to the drive signal of opposite phase.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil. The drive signal is such that nonconducting periods are set before and after a positive current conducting period and the nonconducting periods are set before and after a negative current conducting period. A driver unit generates the drive current in response to the drive signal generated by the drive signal generating unit and then supplies the drive current to the coil. The drive signal generating unit sets the width of a nonconducting period such that, after the drive start of the linear vibration motor, the width of a nonconducting period to be set before at least the first conducting period of the drive signal is shorter than the width of a nonconducting period to be set before each conducting period during steady operation of the linear vibration motor.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil with a nonconducting period inserted between conducting periods. A driver unit generates a drive current in response to the drive signal generated by the drive signal generating unit and supplies the drive current to a coil. An induced voltage detector detects an induced voltage occurring in the coil during the nonconducting period. A zero-cross detecting unit detects the zero cross of the induced voltage detected by the induced voltage detector. The drive signal generator estimates the eigen frequency of the linear vibration motor based on a detected position of the zero cross, and the frequency of the drive signal is brought close to the estimated eigen frequency.

Abstract: An integrated driving apparatus having an elongated shape mounted at a peripheral portion of a display apparatus comprising a display section on a panel substrate comprises a logic section, a power supply circuit section, and a D/A converter. The logic section comprises a digital display data processor and a timing signal generator which generates a timing control signal necessary for the display apparatus and the D/A converter converts digital display data obtained by the digital display data processor into analog data. The power supply circuit section generates a power supply voltage used in the display apparatus using a signal from the timing signal generator. The power supply circuit section and the D/A converter are provided on left and right of the logic section with the logic section therebetween so that the power supply circuit section and the D/A converter are placed adjacent to the logic section along a long side direction of the elongated shape of the integrated driving apparatus.