Abstract: An integrated circuit for controlling operation of a motor of a fan assembly. The fan assembly includes a housing and a fan. The motor is in the housing. The housing is void of sensors. The motor is configured to rotate the fan. The integrated circuit includes a detection module and a first control module. The detection module is separate from the fan assembly. The detection module is configured to detect a voltage induced in a first coil of the motor or a back electromotive force received from the first coil of the motor. The first control module is configured to receive a control signal from a second control module and control the operation of the fan based on (a) the control signal, and (b) the voltage induced in the first coil of the motor or the back electromotive force. The second control module is separate from the integrated circuit.

Abstract: A motor control device has a motor driving circuit for driving a motor, a current detection circuit for detecting a motor current flowing through the motor driving circuit, and a controller for calculating a detected value of the motor current based on an output of the current detection circuit, comparing the detected value with a target value of the motor current, and generating a command value for allowing a motor current of the target value to flow through the motor based on a deviation therebetween, to output the command value to a motor driving circuit. The current detection circuit is configured of a first current detection circuit having a positive first gain and a second current detection circuit having a negative second gain obtained by inverting the first gain.

Abstract: A driving device capable of driving a motor more efficiently is provided. A zero-crossing detection comparator 10 compares a pair of Hall signals H+ and H? having reverse phases and representing a rotor position of a fan motor 6, and generates a level-shifted zero-crossing detection signal S1 at each zero-crossing timing when the Hall signals cross each other. A control circuit 20 receives the zero-crossing detection signal S1, switches a driving phase at each zero-crossing timing to rotationally drive the motor, and regeneratively controls the motor during a duration from a first time point ahead of each zero-crossing timing by a first time width ?1 to a second time point behind each zero-crossing timing by a second time width ?2 shorter than the first time width ?1.

Abstract: A motor drive controller to control a motor via multiple sensors includes a first phase detector to compare respective differential pairs of the sensor signals from the same sensor to detect phases of the rotor, and output a first phase information signal; a second phase detector to compare a respective one of the multiple sensor signals with another sensor signal from the different sensor to detect the phases and output a second phase information signal; a phase divider to divide the phases, detected by the first and second phase detectors, into multiple predetermined phase intervals; a signal selector to select one of the multiple sensor signals in the multiple predetermined phase intervals; and a third phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a third phase information signal.

Abstract: The system contains a controller unit comprising a memory device, a processing unit, and at least one analog-to-digital converter. A power stage has a plurality of switches, wherein the power stage receives a control signal from the control circuit and a power signal from a power source. The power stage drives two windings of the set of three stator windings to rotate a rotor and maintains one stator winding of the three stator windings undriven. The memory device stores a plurality of values for the driven current and a plurality of demodulated undriven winding voltages. The processing unit compares the plurality of values and periodically calculates a rotor sextant while the rotor rotates. The processing unit compares at least two demodulated undriven winding voltage values corresponding to at least two current values within the rotor sextant to calculate the rotor sextant parity and verify the calculation of the rotor sextant.

Abstract: A motor drive controller to drive a motor, based on multiple sensors that generates multiple sensor signals corresponding to different positions of the rotor; including a first phase detector to compare a respective one of the multiple sensor signals with a paired sensor signal from the same sensor to detect phases of the rotor, and output a first phase information signal representing a first detected phase; a phase divider to divide the phases, detected by the first phase detector into multiple predetermined phase intervals; a signal selector to select one of the respective multiple sensor signals from the multiple sensors in the multiple predetermined phase interval; and a second phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a second phase information signal representing a second detected phase.

Abstract: A soft switching control circuit for a DC motor is provided. The soft switching control circuit has an absolute value generating circuit, a threshold voltage generating circuit, and a comparing circuit. The absolute value generating circuit outputs an absolute value signal according to a pair of Hall signals from the DC motor. The threshold voltage generating circuit receives a detected state signal and at least an end voltage of a coil of the DC motor for determining a current on the coil at an actual state change time defined by the detected state signal. According to the determination, the threshold voltage generating circuit outputs a threshold voltage with an adjusted voltage level. The comparing circuit compares the absolute value signal and the threshold voltage so as to generate a state change adjusting signal for modifying the actual state change time.

Abstract: A motor driving device and a driving method thereof is disclosed herein and comprises a PWM converting circuit, an oscillator, a comparator, a controlling unit. The PWM converting circuit converts an analog signal according to an adjustable the highest setting voltage, an adjustable the lowest setting voltage and a controlling signal. The analog signal and a triangular signal generated by the oscillator are inputted to the comparator to compare to output a drive signal to the controlling unit so as to control the motor speed. The motor driving device in the present invention can adjust the motor rotating speed curve to set the lowest rotating speed of the motor so as to achieve the function of changing the motor rotating speed and maintain the lowest torque of the motor to increase the flexibility of the motor speed control.

Abstract: A motor control device has a motor driving circuit for driving a motor, a current detection circuit for detecting a motor current flowing through the motor driving circuit, and a controller for calculating a detected value of the motor current based on an output of the current detection circuit, comparing the detected value with a target value of the motor current, and generating a command value for allowing a motor current of the target value to flow through the motor based on a deviation therebetween, to output the command value to a motor driving circuit. The current detection circuit is configured of a first current detection circuit having a positive first gain and a second current detection circuit having a negative second gain obtained by inverting the first gain.

Abstract: A circuit may be configured to adjust a correction signal for each phase of an electric motor based on a rotational position of a spindle of the electric motor, generate a distorted waveform based on the correction signal, and drive the electric motor in response to the distorted waveform. In some examples, back electromotive force (BEMF) may be determined in order to adjust a motor drive waveform, which may reduce or eliminate motor vibrations. A motor drive signal may be pre-warped (i.e. distorted) such that when the correctional signal and drive signals are combined, there is a reduction in acoustic emissions or motor vibrations. Other parameters, such as cogging torque, may be measured to reduce motor vibration and acoustic emissions.

Abstract: A motor controller is disclosed. The motor controller includes a current detector that is provided in a direct current side of a power converter and that detects direct current information. A determiner determines a size of an offset voltage contained in the detected current information. The determiner calculates the offset voltage by canceling a positive current component by a negative current component both pertaining to the same one phase and contained in the detected direct current information. A modifier modifies the detected direct current information based on the calculated offset voltage.

Abstract: In a multi-phase brushless DC motor, a zero crossing N-bit filter includes a comparator and a phase multiplexer. The phase multiplexer connects each motor phase to each of a positive and a negative input of the comparator, with a switch in each connection to form a switch array. A microprocessor is disposed to operate the switches, and is configured to measure a BEMF for a first phase by opening the switches connecting all other phases to the positive input of the comparator and by opening the switch connecting the first phase being measured to the negative input of said comparator. The comparators output is received by a shift register. The microprocessor is configured to respond to a zero crossing when a majority of bits in the shift register change between high and low.

Abstract: A method for controlling a permanent magnet synchronous motor includes detecting an absolute angular position and using the angular position to calculate a rotational speed of the motor; detecting a voltage of a battery as a power source; calculating a compensated speed from a rotational speed of the permanent magnet synchronous motor based on a torque command, the rotational speed of the permanent magnet synchronous motor, and the battery voltage; generating a d-axis current command and a q-axis current command corresponding to the torque command and the compensated speed; calculating a d-axis voltage command and a q-axis voltage command based on the d-axis current command and the q-axis current command; converting the d-axis voltage command and the q-axis voltage command into three-phase voltage commands based on the detected absolute angular position; and controlling the operation of the permanent magnet synchronous motor based on the three-phase voltage commands.

Abstract: A sensorless commutation circuit and sensorless driving apparatus for a brushless motor includes a voltage divided unit, a control signal output unit, a switch unit and a comparison unit. The voltage divided unit outputs a voltage divided signal according to a phase voltage signal of the brushless motor. The control signal output unit outputs a filter control signal, wherein the filter control signal has a same switching cycle as a pulse width modulation control signal that drives the brushless motor. The switch unit is coupled to the control signal output unit and the voltage divided unit, and outputs a comparison signal according to the filter control signal and the voltage divided signal. The comparison unit is coupled to the switch unit, and outputs a correct commutation signal according to the comparison signal.

Abstract: A circuit includes a comparator having input terminals configured to be coupled across a drive transistor adapted to drive a phase of a motor. The comparator senses a drive current of the motor phase, said sensed drive current represented by a periodic signal whose period is indicative of motor speed. A motor speed calculation circuit receives the periodic signal and processes the periodic signal to determine a speed of the motor.

Abstract: An apparatus includes an integrated circuit (IC) adapted to be powered by a positive supply voltage. The IC includes a charge pump that is adapted to convert the positive supply voltage of the IC to a negative bias voltage. The IC further includes a bidirectional interface circuit. The bidirectional interface circuit includes an amplifier coupled to the negative bias voltage to accommodate a bidirectional input voltage of the IC. The bidirectional interface circuit further includes a comparator coupled to the negative bias voltage to accommodate the bidirectional input voltage of the IC.

Abstract: When a short-circuited FET is identified as one of low-side FETs, maximum phase voltages of three phases are detected when a steering operation is performed by a driver, and the detected maximum phase voltages of the three phases are compared with one another to identify a short-circuit phase. On the other hand, when a short-circuited FET is identified as one of high-side FETs, minimum phase voltages of the three phases are detected when a steering operation is performed by the driver, and the detected minimum phase voltages of the three phases are compared with one another to identify a short-circuit phase.

Abstract: Motor control circuits and associated methods to control an electric motor provide a plurality of drive signal channels at the same phase, resulting in reduced jitter in the rotational speed of the electric motor.

Abstract: The present invention relates to an AC motor control device and, particularly, to provide an AC control device capable of simply setting a state quantity of an AC motor non-linearly variable, in accordance with the motor driving state and using the setting in motor control, the present invention can be achieved by including a state quantity calculating unit (13, 13a, 13b, 13c) for calculating a state quantity corresponding to a coil interlinkage flux which is an internal quantity of the motor, calculating a setting value of the coil interlinkage flux defined on one axis out of two axes, that is, d and q axes, with a function formula using a current defined on the same one of the axes and a function formula using a state variable defined on the other one of the axes.

Abstract: There are provided a circuit for detecting back-electromotive force, a motor driving control apparatus and method using the same, the motor driving control apparatus including: a comparing unit outputting back-electromotive force of a motor apparatus using a plurality of comparators connected to a plurality of phases of the motor apparatus, respectively; a controlling unit controlling the driving of the motor apparatus using the back-electromotive force; and a comparator driving unit activating at least a portion of the plurality of comparators according to a preset operation scheduling.

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: A method and system for a commutation control circuit are provided. The system includes an integrating voltage counter electrically coupled to an electrical power bus, wherein the integrating voltage counter is configured to integrate over time a voltage signal received from the power bus and to generate a trigger signal when the integrated voltage signal equals a predetermined count. The system also includes a plurality of transistor pairs configured to receive a trigger signal generated by the integrating voltage counter and electrically coupled to respective windings of a motor.

Abstract: A motor control apparatus includes a phase sensing circuit, a current sensing circuit, a controller and a driving circuit. The driving circuit receives a first driving signal and then controls a phase switching state of the magnetic pole of the motor so as to drive the motor in accordance with the first driving signal. The phase sensing circuit detects the phase switching state of the magnetic pole to generate and output a phase switching signal to the controller during the motor is operating. The current sensing circuit detects a current flowing through the motor to generate and output a current phase signal to the controller. The controller compares a phase difference between the phase switching signal and the current phase signal to generate and output a second driving signal to the driving circuit. The driving circuit controls the phase switching state of the magnetic pole for driving the motor in accordance with the second driving signal.

Abstract: A method is provided for monitoring a motor having a stator, a rotor and a detector. The stator can receive a driving signal to produce a first magnetic field. The rotor can rotate in a circle relative to the stator. The rotor has a magnetic portion that can emit a second magnetic field in a radial direction. The detector can output a detection signal based on the position of the rotor.

Abstract: In a vehicular rotary electric machine, a switching section includes a bridge circuit having plurality of upper arms and plurality of lower arms. The arms include switching elements. A diode is connected in parallel to each switching element. One end of the switching element of each of the upper arms is connected to a positive terminal of a battery and one end of the switching element of each of the lower arms is connected to a negative terminal of the battery via a vehicle body. The switching section rectifies induced phase voltage of an armature winding. A section sets ON-timing of the switching elements. A section sets OFF-timing of the switching elements. When the switching element of each lower arm is OFF, a detector detects an energization period in which current flows to the diode. A calculator calculates a rotation frequency based on the detected energization period.

Abstract: A first calculation unit subtracts third digital data which indicates the minimum value of the duty ratio from first digital data which indicates the duty ratio of the PWM driving operation. A slope calculation unit generates slope data which is dependent on the temperature based upon second digital data which indicates the temperature. A second calculation unit multiplies the slope data by the output data of the first calculation unit. A third calculation unit sums the output data of the second calculation unit and the third digital data. A selector receives the output data of the third calculation unit and the third digital data, selects one data that corresponds to the sign of the output data of the first calculation unit, and outputs the data thus selected as a duty ratio control signal.

Abstract: According to one embodiment, a low frequency drive control circuit for use with an inductive load comprises a comparator configured to receive a high frequency signal at a first input and a smoothly varying low frequency signal for modulating the high frequency signal at a second input. The comparator is further configured to produce a pulse width modulated output of the low frequency drive control circuit for use in generating a smoothly varying low frequency load current in the inductive load. In one embodiment, the inductive load can comprise a DC brushed motor. In one embodiment, the low frequency drive control circuit can be implemented as part of an integrated circuit further comprising a switching circuit configured to use the pulse width modulated output of the comparator to generate the smoothly varying low frequency load current, which may be a substantially sinusoidal load current, for example.

Abstract: One embodiment includes a back-electromagnetic force (BEMF) sense system. The system includes a sense amplifier configured to measure an amplitude of a selected one of a plurality of phase voltages relative to a center tap voltage associated with a servo motor for the calculation of an associated BEMF voltage. The plurality of phase voltages can be provided to the sense amplifier via a respective plurality of control nodes. The selected one of the plurality of phase voltages on a respective one of the control nodes can be selected based on coupling the other of the plurality of control nodes associated with the other of the plurality of phase voltages to a voltage source configured to provide a predetermined voltage magnitude.

Abstract: The brushless motor driver includes a sample and hold circuit which samples and holds a first value of the first comparison signal in a first case in which a current is forced to flow from a first phase coil of the three-phase brushless motor to a second phase coil and no current is forced to flow to a third phase coil in a first period having a preset setting time and a second value of the first comparison signal in a second case in which a current is forced to flow from the second phase coil to the first phase coil and no current is forced to flow to the third phase coil in a second period having the preset setting time subsequent to the first period. The brushless motor driver includes an addition circuit which adds up the first value and the second value sampled and held by the sample and hold circuit and outputs an addition signal depending upon a result of the addition.

Abstract: An image forming apparatus includes an engine unit to perform an image forming job; an engine control unit to control the operation of the engine unit; a brushless direct current (BLDC) motor to drive the engine unit; a sensor unit to sense electric angle information and driving velocity information of the BLDC motor; a communication interface to receive a digital control command with respect to the BLDC motor from the engine control unit; a driving signal unit to generate a driving signal to control the BLDC motor; and a digital control unit to control the operation of the driving signal unit in a digital phase locked loop (PLL) manner for feedback controls the BLDC motor, based on the received digital control command, the detected electric angle information and the driving velocity information and a digital gain value as a control factor with respect to the BLDC motor.

Abstract: A motor control circuit and associated techniques can adjust a phase of a motor drive to keep a rotational reference position of an electric motor at the same relative phase as a zero current in a motor winding at different motor speeds and as the motor accelerates and decelerates. In some embodiments, a particular circuit and technique can be used to detect the zero current in the motor winding.

Abstract: An apparatus includes an inverter including a high-side switch coupled to a low-side switch, the inverter generating a time-varying drive current from a plurality of drive control signals, a positive rail voltage, and a negative rail voltage wherein controlling the switches to generate the time-varying drive current produces a potential transitory overshoot condition for one of the switches of the inverter; a drive control, coupled to the inverter, to generate the drive control signals and to set a level of each of the rail voltages responsive to a plurality of controller signals; and a controller monitoring one or more parameters indicative of the potential transitory voltage overshoot condition, the controller dynamically adjusting, responsive to the monitored parameters, the controller signals to reduce a risk of occurrence of the potential transitory voltage overshoot condition.

Abstract: A driving apparatus has a correction value output unit for outputting correction values ?Ta and ?Tb to correct differences between signals which are output from an A sensor a B sensor when an A-phase coil and a B-phase coil are not energized and signals which are output from the A sensor and the B sensor when the A-phase coil and the B-phase coil are energized. An energization direction of the A-phase coil is switched on the basis of a time A which is measured by a time measurement unit and the correction value ?Ta which is output from the correction value output unit. An energization direction of the B-phase coil is switched on the basis of a time B which is measured by the time measurement unit and the correction value ?Tb which is output from the correction value output unit.

Abstract: A system is disclosed for controlling motor switching in a sensorless BLDC motor having a set of three stator windings. A controller unit includes a control signal generator, a memory device, a processing unit, a signal acquisition device, and an analog-to-digital converter. A power stage having a plurality of switches receives a control signal from the control signal generator and a power signal from a power source. The power stage drives two windings of the set of three stator windings with an asymmetric pulse width modulation signal and leaves one stator of the three stator windings undriven. The processing unit acquires a demodulated measured voltage on the undriven winding. The processing unit also communicates with the power stage to change which two windings of the three stator windings are driven when the demodulated measured voltage surpasses a threshold.

Abstract: The two-phase modulation control inverter unit includes a plurality of switching devices, a shunt resistor and a controller. The switching devices drive a three-phase motor. The shunt resistor is connected between a direct-current power supply and the switching devices. The controller reads a voltage applied to the shunt resistor in a read cycle, computes command voltages based on the read voltage, and uses the command voltages and carrier signals to compute three control signals. The read cycle corresponds to two or more signal cycles of each carrier signal. Each control signal has a pulse for each signal cycle of the corresponding carrier signal. The controller integrates a plurality of pulses of each control signal in the read cycle into one or more pulses. The controller reads a voltage applied to the shunt resistor at the time of outputting of the integrated one or more pulses in the next read cycle.

Abstract: The system discloses structure for synchronizing sequential phase switching in driving a set of stator windings of a multi-phase sensorless brushless permanent magnet DC motor. A drive voltage drives a plurality of the stator windings thereby producing a magnetic field. On an undriven stator winding among the stator windings, a voltage induced by the magnetic field is sampled. The induced voltage changes as a function of a magnetic rotor transitioning across a plurality of angular positions. A first value corresponding to the sampled voltage induced on the currentless winding is compared with a commutation threshold to determine a proper commutation point. The system is switched to a next drive configuration of the sequence when the first value surpasses the threshold.

Abstract: An exemplary fan rotation speed control system for adjusting rotation speed of a fan includes a switch input module, a rotation speed control module, a signal collecting module, a decoding module, and a display module. The switch input module inputs a rotation speed signal in the rotation speed control module. The rotation speed control module outputs a first direct current (DC) voltage to provide power supply for the fan according to the rotation speed signal. The rotation speed control module adjusts values and directions of the first DC voltage according to the rotation speed signal. The signal collecting module collects rotation information of the fan. The rotation speed control module receives the rotation information and decodes the rotation information to rotation speed values by the decoding module which are displayed on the display module.

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 of determining the position of a rotor of a permanent-magnet motor. The method includes sequentially exciting and freewheeling a winding of the motor. The winding is freewheeled for a freewheel period in response to current in the winding exceeding a current limit. The method also includes measuring a parameter that corresponds to either the magnitude of current in the winding at the end of the freewheel period or the interval between the start or end of the freewheel period and the time at which current in the winding exceeds the current limit. The measured parameter is then compared against a threshold and the rotor is determined to be at a predetermined position when the measured parameter is less than or greater than the threshold.

Abstract: A triangle wave generator (4) measures the phase difference between a triangle wave (CA) and the rotor electrical angle (?m) during a first cycle in which the rotation rate of a rotor (7) is detected, and changes the frequency of the triangle wave (CA) when the value of the phase difference between the triangle wave (CA) and the rotor electrical angle (?m) exceeds a threshold value, thereby allowing rapid response to changes in rotor rotation when PWM control is performed.

Abstract: A sensorless commutation circuit and sensorless driving apparatus for a brushless motor includes a voltage divided unit, a control signal output unit, a switch unit and a comparison unit. The voltage divided unit outputs a voltage divided signal according to a phase voltage signal of the brushless motor. The control signal output unit outputs a filter control signal, wherein the filter control signal has a same switching cycle as a pulse width modulation control signal that drives the brushless motor. The switch unit is coupled to the control signal output unit and the voltage divided unit, and outputs a comparison signal according to the filter control signal and the voltage divided signal. The comparison unit is coupled to the switch unit, and outputs a correct commutation signal according to the comparison signal.

Abstract: In a method for the determination of a current initial rotational position of a rotor and in an arrangement for carrying out same, an incremental position encoder outputs an output signal. The output signal is produced by superposition of a chronologically random and systematically fluctuating signal interference on a basic signal, and composed of at least two component signals which change periodically in accordance with the rotational position of the rotor and are in a fixed angular relationship to one another. To determine the position, the output signal is used exclusively. The current initial rotational position of the rotor relative to a reference initial rotational position is determined by comparing the time profile of the portion of the systematically fluctuating signal interference of a current measured value sequence of the signal and the measured values of a signal sequence acquired starting from the reference initial rotational position.

Abstract: A self-adapting soft-starter device includes an electric current limiter limiting electric current supplied to the motor to a preset maximum current limit, a ramp-up time determiner determining the actual ramp-up time of the electric motor, a storing device storing a preset minimum ramp-up time, a comparator comparing the determined actual ramp-up time with the preset reference ramp-up time, a replacing device replacing the preset maximum current limit with an auto-adapted current limit based upon the outcome of the comparison between the determined actual ramp-up time and the preset reference ramp-up time. The soft-starter automatically optimizes the maximum current limit driven by the motor to match its load requirements which is useful to cater for load variations with time during the lifetime of the product in the application by avoiding the need for human intervention to change the soft-starter settings. Wear and tear is also reduced, extending motor lifetime.

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 motor control apparatus includes a phase sensing circuit, current sensing circuit, phase lock loop, controller and driving circuit. The phase sensing circuit detects a phase switching state of a magnetic pole of a motor circuit, then generates and outputs a phase switching signal to the phase lock loop during motor operation. The current sensing circuit detects current flowing through a coil of the motor to generate and output a current phase signal to the phase lock loop. The phase lock loop compares a phase difference between the phase switching signal and the current phase signal to generate and output a phase-switch controlling signal to the controller. The controller generates and outputs a driving signal to the driving circuit in accordance with the phase-switch controlling signal. The driving circuit controls the phase switching state of the magnetic pole to drive the motor in accordance with the driving signal.

Abstract: Disclosed is a hall sensor signal generating device which includes a rotor which has a magnetic property and rotates on the basis of a rotary axis; a hall sensor unit which is disposed to be spaced apart from a stator disposed outside the rotor; and a clock synchronization unit which receives a driving clock, performs synchronization between the driving clock and a hall sensor signal output from the hall sensor unit, and outputs the synchronized driving clock and the synchronized hall sensor signal.

Abstract: First and second A/D converters perform analog/digital conversion of first and second signals of a Hall signal so as to generate third and fourth signals as digital signals. A differential conversion circuit generates a fifth signal as a single-ended signal that corresponds to the difference between the third and fourth signals. An offset correction circuit corrects offset of the fifth signal so as to generate a sixth signal. An amplitude control circuit stabilizes the amplitude of the sixth signal to a predetermined target value, and generates its absolute value, thus generating a seventh signal. A control signal generating unit generates a control signal based upon the seventh signal. A driver circuit drives a motor according to the control signal.

Abstract: A motor drive controller to control a motor via multiple sensors includes a first phase detector to compare respective differential pairs of the sensor signals from the same sensor to detect phases of the rotor, and output a first phase information signal; a second phase detector to compare a respective one of the multiple sensor signals with another sensor signal from the different sensor to detect the phases and output a second phase information signal; a phase divider to divide the phases, detected by the first and second phase detectors, into multiple predetermined phase intervals; a signal selector to select one of the multiple sensor signals in the multiple predetermined phase intervals; and a third phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a third phase information signal.

Abstract: A motor drive controller to drive a motor, based on multiple sensors that generates multiple sensor signals corresponding to different positions of the rotor; including a first phase detector to compare a respective one of the multiple sensor signals with a paired sensor signal from the same sensor to detect phases of the rotor, and output a first phase information signal representing a first detected phase; a phase divider to divide the phases, detected by the first phase detector into multiple predetermined phase intervals; a signal selector to select one of the respective multiple sensor signals from the multiple sensors in the multiple predetermined phase interval; and a second phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a second phase information signal representing a second detected phase.

Abstract: A method of the Pulse Amplitude Modulation for the Sensorless Brushless motor, which includes a start-up circuit, a phase detect circuit, a phase commutation circuit, a driving circuit, BEMF detection circuit, and frequency detector, utilizes the control signal of the phase commutation circuit to control the driving circuit so as to drive the outer motor coil and detect the control signal for the driving motor driving circuit by a detection circuit. The motor system can be controlled to reduce the discharge speed to avoid the motor driving circuit shutdown and further speed up the start-up time for the next charging period of the motor driving circuit to achieve the effect of low speed rotation and power saving.