Abstract: A coffee machine including a grinder configured to grind coffee beans, and a coffee machine devised to be able to bring an air volume for separating waste such as chaff as close as possible to a target air volume. A first grinder configured to grind coffee beans; a fan configured to generate a wind pressure by rotating to separate waste from the ground beans ground by the first grinder; a fan motor configured to cause the fan to rotate; and a control unit configured to control rotation of the fan motor according to a set value, and the control unit acquires information (the number of rotation pulses) related to a rotation speed of the actually rotating fan motor, corrects the set value based on the acquired information, and controls the rotation of the fan motor according to the corrected set value.

Abstract: An actuator includes a polyphased brushless motor having a two-wire connection for receiving a modulated power supply signal with a cyclic ratio or a modulated frequency, supplied by a motor control unit. The actuator also includes an electronic circuit having a microcontroller and a power stage delivering the power supply signals of the coils of the brushless motor, and a power supply stage including a rectifier and/or a filtering of the modulated signal for delivering a continuous power supply signal of the electronic circuit.

Abstract: A soft start circuit for a mixer is provided that includes an input for receiving an analog voltage representing a raw target speed; a current mirror for causing a speed target to change at a constant rate when the raw target speed represents a change from a current speed; and a comparator for receiving and comparing the raw target speed and an output from the current mirror and restricting the output from exceeding the raw target speed in order to restrict a soft start to only impede the speed target change when the raw target speed is increasing while not impeding the speed target change when the raw target speed is decreasing. The output of the soft start circuit is an analog representation of a soft start modified desired target speed.

Abstract: A feedback line to an embedded controller from a component that intermittently sends data not distinguishable by the embedded controller initiates an error if data expected at the embedded controller is not distinguishable, such as with low cooling fan speed tachometer feedback. The embedded controller has a resistor divider circuit associated with the component that provides a high or low pin value at the embedded circuit based upon whether a component interfaces with a pin, such as a pulse width modulation output. The embedded controller checks for presence of the component in the absence of feedback as a reference to know whether an error exists relating to component feedback.

Abstract: Systems and methods for operating an inverter that is electrically coupled to a battery and an electric machine that provides propulsive force to vehicle are described. The systems and methods may selectively adjust a duty cycle of an inverter transistor responsive to battery voltage and a dead time between when a first transistor is deactivated and when a second transistor is activated.

Abstract: To provide a multi-phase power conversion device control circuit capable of preventing switching elements and driver circuits of a multi-phase power conversion device from being damaged even when arm short circuits have occurred to a plurality of phases simultaneously. The control circuit includes: a current detection unit configured to detect a current flowing through the switching element as a voltage value; an overcurrent detection unit configured to, when a voltage value detected by the current detection unit is higher than a first reference voltage, output an individual overcurrent detection signal Scu; and an overcurrent state control unit configured to, when overcurrent state is detected at the current detection unit of each of two or more phases, output a multi-phase overcurrent signal and short-circuit the control terminal of the switching element to an emitter terminal thereof.

Abstract: Between the lower stage in respective phases of inverter circuit and the negative potential side, shunt resistors are inserted for respective phases. The potential differences across shunt resistors occurring by current flowing through shunt resistors are amplified by amplifier unit. From the output of amplifier unit, current detecting unit detects current of each phase flowing through motor formed by a sensorless brushless DC motor. Rotation detecting unit calculates the rotation speed and position of motor based on the current detected by current detecting unit. This structure makes it possible to directly detect solely the current flowing through the windings of motor. Therefore, it becomes possible to accurately detect the current of the motor windings, and the ventilation device can maintain the ventilation air volume from a small air volume to a large air volume always at a constant value.

Abstract: A duty cycle detecting circuit for pulse width modulation (PWM). The circuit includes a clock generating circuit, a sampling circuit and a calculation circuit. The clock generating circuit is for generating a clock signal. The sampling circuit receives a PWM signal and the clock signal, samples the PWM signal based on the clock signal, and generates a sampling signal. The calculation circuit is for calculating the duty cycle of the PWM signal based on the sampling signal.

Abstract: A motor driving apparatus is applied to a fan and motor mechanism and a voltage supply unit. The motor driving apparatus includes a motor driving unit, a voltage division resistor, a first resistor, a first switch unit, a second resistor, a second switch unit, a third resistor, a third switch unit, a transistor switch, and a pulse width modulation unit. The first switch unit, the second switch unit, and the third switch unit are configured to select the rotational speed upper limitation of the fan and motor mechanism for suppressing noise.

Abstract: A lower limit value setting unit (52) variably sets a lower limit value (Vth) of a target voltage (Vh*) in a range of a voltage that is higher than the maximum value of voltages (Vb1, Vb2) of power storage devices and is not affected by a dead time provided for converters, based on temperatures (Tb1, Tb2) and required electric powers (Pb1*, Pb2*). A maximum value selection unit (53) sets the maximum value among the voltages (Vb1, Vb2) of the power storage devices and required voltages (Vm1*, Vm2*) of motor-generators, as the target voltage. A target voltage limiting unit (54) compares the target voltage with the lower limit value (Vth), and if the target voltage is lower than the lower limit value (Vth), the target voltage limiting unit (54) sets the lower limit value (Vth) as the target voltage (Vh*).

Abstract: Having a correlative relation indicator for indicating a correlative relation so that the supply current to be supplied to an inverter circuit may be varied proportionally to the voltage applied to the inverter circuit, a supply current value controller controls the average current to be supplied to the inverter circuit so as to be equal to the value of the supply current indicated by the correlative relation indicator, and therefore if the pressure loss or the static pressure is changed, a wind volume-static pressure of high precision extremely small in the changing amount of wind volume is realized.

Abstract: A control device of a synchronous machine is disclosed. The control device includes an inverter configured to provide an output current to a synchronous machine. A controller configured to control the output current and to estimate a voltage command, at least in part, by using pulse width modulation to choose a non-zero vector at a time when the inverter is not driving the synchronous machine with the output current. The estimating the voltage command is performed without using a zero vector. A phase angle and angular velocity estimating section configured to estimate a phase angle and an angular velocity of a rotor of the synchronous machine based, at least in part, on an inductance value, an induction voltage value, the voltage command, and the output current. The controller is further configured to control the output current based, at least in part, on the phase angle and the angular velocity.

Abstract: The invention relates to a hand-guided electric tool having a motor and a pulse width modulator for generating a pulse width modulated signal for operating the motor. A unit is provided for reducing the EMC interferences emitted by the electric tool.

Abstract: Disclosed is a multi-speed control apparatus for a fan motor. The apparatus includes a driving member, a motor speed sensing member, a resistor circuit, a voltage-division resistor, and a multi-segment switch. The driving member has a controlled end connected with the multi-segment switch. The driving member has an output end connected with the fan motor. The driving member has a detection end connected with the motor speed sensing member. The resistor circuit includes some resistors with various resistances. The multi-segment switch interconnects the resistor circuit, the voltage-division resistor, the controlled end of the driving member, and a voltage source. This switch is optionally connected to the resistor disposed in the voltage source or voltage-division resistor. An input voltage is created across the resistor by dividing the voltage. The driving member is therefore provided for driving the fan motor to a rotating speed according to the input voltage.

Abstract: A control circuit is electrically connected to at least one fan device. The fan device has a motor and generates a sensing signal. The control circuit receives a power-source signal and the sensing signal and includes a power converting unit, a control unit and a switch unit. The power converting unit receives the power-source signal and thus respectively outputs a first power-source signal and a second power-source signal according to the power-source signal. The control unit receives the first power-source signal and the sensing signal and thus generates a control signal according to the sensing signal. The switch unit receives the control signal and generates at least one switch signal according to the control signal. The fan device receives the second power-source signal and the switch signal and drives the motor according to the switch signal.

Abstract: A fan motor control device for controlling the soft start of a fan motor is disclosed. The fan motor control device comprises a converter, a starting capacitor, and a controller. The converter sends out a control signal to the controller based on an input pulse-width modulation signal. The starting capacitor is coupled between a voltage source terminal and a controlled terminal of the controller. Thereby, based on an input voltage to the controlled terminal, the controller controls the soft start of the fan motor. For the soft start period, the magnitude of the input voltage is determined by the base working voltage outputted via the voltage source terminal. While for normal operation, based on the input voltage to the controlled terminal, the controller controls the speed of the fan motor, with the magnitude of the input voltage determined by the control voltage outputted by the converter.

Abstract: A computer program product stored in a computing device has a processor and a communication interface to determine cooling specifications of a remote housing. The computer program product includes a machine-readable storage medium and machine-readable program code, stored on the machine-readable storage medium. The machine readable program code includes instructions, which when executed, to cause the processor to interact with a user to obtain fan motor operating parameters and conditions. Motor operation is then controlled in accordance with the user-provided operating parameters and conditions.

Abstract: A fan delay controlling apparatus includes a connector connected to a fan of an electronic device, a power supplying module connected to the connector, and a power controlling module connected to the power supplying module. The power supplying module is connected to a fan power source and a stand-by power source. The power controlling module controls the power supplying module supply power to the fan when the electronic device including the fan powers off until an ambient temperature is lower than a predetermined value.

Abstract: In a method for reliably monitoring the speed of a moveable coordinate measuring device, a first value of the speed is calculated from measured values of the coordinate measurement system. The measured values contain information on positions of the coordinate measuring device. The measured values are further used to determine the coordinates of a measurement object. A second value of the speed is ascertained from measurement signals of at least one additional movement sensor. The measurement signals can also be used for controlling a drive device of the coordinate measuring device. A fault signal can be generated if the first value and/or the second value deviate from one another, from a predetermined value and/or a limit value according to a predefined criterion.

Abstract: A motor driving circuit generates pulse driving signals, and controls the ON/OFF state of a switching circuit connected to a coil of a motor which is to be driven, thereby controlling the conduction period of the motor. A driving signal generating circuit generates the driving signals such that they are pulse modulated according to the torque target value for the motor, and outputs the driving signals to the switching circuit. A current detection circuit detects the current flowing through the coil of the motor. A current limiting circuit controls the logical values of the driving signals generated by the driving signal generating circuit such that the current detected by the current detection circuit does not exceed a predetermined current upper limit. The current limiting circuit increases the current upper limit according to the time elapsed in the starting operation of the motor. After the starting operation of the motor, the current upper limit is set to a predetermined fixed value.

Abstract: When the fan inserted in the fan header is a 4-pin fan, the control chip outputs PWM signals with different duty factors to the control pin of the fan header, to automatically change the rotary speed of the 4-pin fan. When the fan inserted in the fan header is a 3-pin fan, the control chip outputs the PWM signals whose duty factor changes with temperature of a chip under the fan to control the first power source to provide a voltage to the adjusting circuit. The adjusting circuit rectifies the voltage output from the first power source as an analog voltage signal to the control circuit. The control circuit controls the third power source to output a changeable driving voltage to the power pin of the fan header to control the rotary speed of the 3-pin fan.

Abstract: A master station has a master-station transmission circuit that extracts a serial monitor signal so as to convert a control data signal into monitor data by changing a duty ratio of negative and positive voltage-level periods, converting the control signal into a serial pulsing voltage signal, transmitting a monitor data signal that is superimposed on the serial pulsing voltage signal, and detecting the presence or absence of a signal of a current that flows during the negative and positive voltage-level periods. A plurality of slave stations respectively have a slave-station transmission circuit that identifies a duty ratio of the positive and negative voltage-level periods relative to each serial pulsing voltage signal, that extracts a control data signal so as to output the data to a controllable unit of the slave station.

Abstract: An aspect of the invention is a method and a device for controlling a rotating field machine having several phase windings, which can be controlled by means of pulse width modulation, wherein a pulse width modulation controller is adapted in such a way that an individual winding of the phase windings of the rotating field machine is energized at a specifiable sampling time.

Abstract: Disclosed is a drive circuit for generating the drive current used to energize the windings of a motor. The drive circuit includes a data processing unit that produces two outputs used to control an H-bridge and generation of the drive current. One output, a commutation signal, controls the timing of generation of drive current. The drive current in turn is determined based on the other output, a speed signal. The speed signal waveform includes blanking portions to avoid occurrences of shoot through in the H-bridge.

Abstract: A motor control apparatus provided with an inverter for successively commutating the current to a motor using a PWM signal; a PWM signal generating device for generating the PWM signal using a carrier signal; a rotational state quantity sensor for detecting a rotational state quantity; a phase difference detecting device for detecting the phase difference between the carrier signal and the rotational period based on the rotational state quantity; a frequency setting device for setting a frequency of the carrier signal to a value in accordance with a multiplier for one period in terms of electrical angle of the rotational period of the motor, when the rotational frequency is equal to or greater than a specified frequency and the phase difference is equal to or less than a specified value; and a synchronizing device for synchronizing a control period of the carrier signal to the rotational period.

Abstract: A method for controlling a fan speed is disclosed. The fan cools a CPU in a computer. The method includes defining a CPU-max-temp value of a CPU, such that the first fan speed is linearly enhanced with the increase of a real temperature value of the CPU, when the real temperature value of the CPU is lower than the CPU-max-temp value, and changing the CPU-max-temp value to a higher CPU-max-temp value in a basic input output system. A second fan speed is linearly enhanced with an increase of the real temperature value, when the real temperature value is lower than the higher CPU-max-temp value. The second fan speed is less than the first fan speed at the real temperature value.

Abstract: A power converter circuit for providing maximum utilization of a DC bus voltage to a two-phase Permanent Magnet Synchronous Motor (PMSM) is disclosed. The circuit includes first, second, and third nodes, each node being the junction between series connected high and low side switches connected across a DC bus; a PMSM having first and second windings and a star point at which the first and second windings are coupled to each other, the first winding having a terminal connected to the first node, the second winding having a terminal connected to the second node, and the star point being connected to the third node; and a controller for performing a three-point Pulse Width Modulation (PWM) coupled to a gate of each switch.

Abstract: The invention relates to a method for increasing the capacity of an installation used to carry out an industrial process in an economical and sustainable manner. Said method consists of the following steps: process variables relevant to the capacity of the installation are determined; said process variables are monitored during variable operating conditions of the installation; and a very small control reserve of the control loops of the installation is established on the basis of the monitored process variables.

Abstract: A method of controlling the velocity of a voice coil motor (VCM), including sensing a voltage difference between the VCM and a sense resistor and driving a velocity control loop (VCL) based on the voltage difference. There is also a control loop circuit, including a current output connected to drive a voice coil motor, the voice coil motor producing a back electromagnetic field (BEMF) voltage. The circuit also includes a sense resistor connected to the BEMF output, and a BEMF resistive network comprising a first resistor and a second resistor. The circuit also includes a velocity control loop (VCL) connected to control the voltage output according to a voltage difference between (i) a junction of the sense resistor and the current output and (ii) a junction of the first resistor and the second resistor.

Abstract: A method is proposed for supplying electrical power to a DC motor (16) which can be commutated electronically via a semiconductor power output stage (28), preferably a three-phase DC motor, through which a control unit (22) passes current in blocks, corresponding to the signals from a rotor position sensor (20). Current is passed through the motor (16) variably in steps, in such a manner that the magnitude and/or the duration and/or the trigger angle of the current blocks can be varied as a function of the rotation speed and/or of the load, with respect to the profile of the induced voltage (E).

Abstract: The present invention is aimed at provision of a control apparatus for and a control method of controlling a motor for a vehicle driven by a driving circuit that operates according to a pulse width modulation (PWM) signal. Measurement of a duty of an output signal from the driving circuit is executed, and a difference between the measured duty and a target duty in a PWM control is then obtained to further execute setting of a correction value for correcting the target duty based on the above difference and to generate the PWM signal based on the corrected target duty.

Abstract: An electronic control circuit controls a brushless DC motor. It includes an input power supply control circuit. A microcontroller integrated circuit has control functions to control a brushless DC motor. Additional control functions are provided by software program instructions, which when executed, cause the microcontroller integrated circuit to perform additional control functions for the brushless DC motor.

Abstract: A fan rotation speed control circuit of a power supply system is provided, which is applicable for controlling the rotation speed of the fan according to a loading state outputted by the power supply system. The fan rotation speed control circuit of the power supply system includes a waveform generating module, for generating an oscillating waveform signal; a current retrieving module, for retrieving a current signal corresponding to the loading state; a rotation speed control signal generating module, for comparing the oscillating waveform signal with the current signal, and generating a rotation speed control signal; a signal amplifying module, for amplifying an amplitude of the rotation speed control signal and outputting the amplified rotation speed control signal to the fan, so as to control the rotation speed of the fan.

Abstract: A fan speed control circuit is used for controlling rotation speed of a fan. The fan speed control circuit receives a pulse width modulation (PWM) signal from a system and comprises a programmable control unit and a current control unit. The programmable control unit receives the PWM signal, is connected to a Hall element for receiving a voltage signal therefrom, and provides a control signal. The current control unit takes the control signal to control current flowing through a stator coil unit of the fan so as to control the speed of the fan. The programmable control unit has a program written for the PWM signal, and when the fan speed control circuit is used in another system with a different PWM signal, the programmable control unit can be given a new program for the different PWM signal for controlling the speed of the fan.

Abstract: Disclosed is a starting device and method for eliminating a peak current introduced when an inductive circuit such as a motor or a direct-current (DC) motor is actuated, The starting device includes a signal generator electrically connected to the inductive circuit and generating a first signal corresponding to a signal output by the inductive circuit, a comparative circuit electrically connected to the signal generator for converting the first signal to a second signal to be compared with a reference signal to generate a control signal, and a controlling device electrically connected with the inductive circuit and the comparative circuit for receiving the control signal and gradually increasing a current input into the inductive circuit corresponding to the control signal, thereby eliminating the peak current introduced when the inductive circuit is actuated.

Abstract: In a PWM-controlled motor, a motor rotation frequency f, lock determination frequency d, and power supply voltage E are acquired (S1 to S3). The d is compared to the f (S4). When f is not less than that of d, Max.Duty is calculated by the following equation for setting: Max.Duty=D0*Kf (S5, S6). D0 is an allowable Duty value and can be calculated by [DP0=a?bE] (a: fixed Duty value, b: Duty characteristic coefficient). Kf is a frequency adjustment coefficient. Kf corrects the allowable Duty value D0 in accordance with the motor rotation frequency f and can be calculated by the following equation: Kf=1+(f?d)/c (c: restriction start frequency, d: lock determination frequency). When f is less than d, Max.Duty=D0 is set (S7, S6). When the motor enters a locked state, the Duty value is suppressed to not more than the allowable Duty value D0 to thereby suppress a lock current. This reduces a lock current at low temperature time to prevent demagnetization of a magnet as well as reduces a load of a switching device.

Abstract: An improved fan arrangement features a radial or diagonal fan (370) with which a direct current motor (32) is associated as its drive motor, further comprising a digital control element (23, 24) which executes a program, for controlling the current flowing through the direct current motor (32), which program is so configured that it applies a substantially constant current in the motor (32) in the working rotation speed range of the fan.

Abstract: A control system and a method of using the same for an electric machine having a random number generating module generating a random number ranging from a first value to a second value, a multiplying module multiplying the random number and a sample rate to generate an random delay value; and a delay limiter module limiting the random delay value as a function of speed of the electric machine and generating a limited delay value.

Abstract: A method and system for providing sensorless brushless DC motor control using predictive switch timing requires connecting a stator coil in a bridge configuration, applying a positive excitation voltage across the coil for a predetermined time period, deactivating the excitation voltage, and monitoring the voltage (VEMF) generated due to electro-motive force (EMF) across the coil. The polarity of VEMF changes when the rotor has moved a known distance—typically 90°. After detecting a polarity change, a negative excitation voltage is applied across the coil, deactivated, and VEMF monitored to detect a polarity change. This sequence is repeated to maintain the rotation of the rotor. The motor is preferably set into motion using a start-up routine, which also determines the predetermined time period used during steady-state operation.

Abstract: A method is specified for controlling a polyphase brushless electric motor, wherein the motor phase currents which are associated with the phases are produced by clocked variation of the respectively applied electrical potential. In this case, the motor phase currents flow back from the electric motor via a common return line with the peak current value in the return line being detected and being included in a controlled variable. Furthermore, a circuit configuration is specified, which is provided in a corresponding manner in order to carry out the control method. The control method and the circuit configuration allow the motor phase currents to be taken into account in the control of the electric motor in a simple and cost-effective manner.

Abstract: The invention teaches a brushless DC motor, comprising a brushless DC motor unit and a controller unit, wherein the brushless DC motor unit comprises a stator assembly, a permanent magnet rotor assembly magnetically coupled with the stator assembly, an enclosure supporting the installation of stator assembly and the permanent magnet rotator assembly, an end shield installed at the end of the enclosure, the rotating shaft of the permanent magnet rotor assembly projecting out of the end shield; the controller unit comprises an integrated power module, a microprocessor unit, a rotor position sensing circuit, a power source circuit, an I/O interface circuit, a current-sensing circuit, and a controller box; and the controller unit is electrically connected to the brushless DC motor unit.

Abstract: Taught herein is a controller for a direct current brushless motor connected to a high voltage control system, comprising a microprocessor and an input/output interface circuit connected between the high voltage control system and the microprocessor; wherein the input/output interface circuit is a step-down circuit for transforming a high voltage control signal into a low-voltage control signal. The controller enables the high voltage control system to cooperate with motor, therefore a user is not necessary to design a new high voltage control system when replacing the conventional AC motor with the DC brushless motor, which saves time, and reduces cost.

Abstract: An integrated control and power driving system moves a read/write head carrying arm over the surface of a disk. The integrated control and power driving system is applicable to a spindle motor, a mass storage disk drive and a voice-coil motor, for example, and includes a first chip and a second chip. The first chip integrates the output power stages driving the motors, and has an interface for outputting feedback signals representing functioning conditions of the voice-coil motor and of the spindle motor, and for receiving digital control signals of the output power stages. The second chip integrates logic drive and control circuitries of the power stages and an interface for receiving the feedback signals output by the first chip, and for transmitting to the first chip the digital control signals.

Abstract: An inductive load driving device includes two inductive loads (20A, 20B) connected to a power source (21), two switching elements (15A, 15B), which are connected in series to the two inductive loads, respectively, their on/off are controlled by a pulse width modulation signal, respectively, and a control device (30), which outputs the pulse width modulation signal to each of the two switching elements, and the pulse width modulation signal is configured such that a rising edge of one pulse of the pulse width modulation signal to be output to one switching element starts between an end point of a rising edge and a start point of a trailing edge of one pulse of the pulse width modulation signal to be output to the other switching element, and a time from a start point of a trailing edge to an end point of the trailing edge of the one pulse of the pulse modulation signal to be output to one switching element does not overlap with a time from the start point of the trailing edge to an end point of the trailing ed

Abstract: A motor speed control integrated circuit which controls a rotational speed of a motor by controlling the amount of current flowing through a drive coil of the motor. The integrated circuit comprises a first input terminal to have an analog speed-specifying signal in analog amount specifying the rotational speed of the motor input thereto; a second input terminal to have a digital speed-specifying signal in digital amount specifying the rotational speed of the motor input thereto; a reference voltage circuit that generates a reference voltage corresponding to the analog speed-specifying signal and/or the digital speed-specifying signal; a comparator that compares a speed voltage corresponding to the actual rotational speed of the motor and the reference voltage; and a control signal generator that generates and outputs a control signal for controlling the amount of current flowing through the drive coil based on the comparing result of the comparator.

Abstract: The invention is directed to a system and method for regulating a load (such as a CPU). A pulse-width-modulation (PWM) regulator calculates the duty cycle of the control pulse from a PWM controller, and then compares the duty cycle to a predetermined threshold. Thereafter, the PWM regulator regulates working conditions, such as clock frequency, supplied voltage, or fan spin speed, based on the above comparison.

Abstract: An apparatus includes a multi-phase inverter, a fault detector to indicate a detection of a fault, a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed, and a controller. The controller is operable to apply either an open-circuit response or a short-circuit response to the multi-phase inverter. The open-circuit response is applied when the speed of the PM motor is greater than the transition speed and a fault is detected. The short-circuit response is applied when the speed of the PM motor is less than the transition speed and the fault is detected. The transition speed is either a fixed predetermined speed or an adjusted predetermined speed.

Abstract: A PWM controller for a direct current brushless motor comprising first and second windings includes a motor drive circuit receiving pulse width modulation control signals to drive the first and the second windings; and a control circuit having inputs coupled to the first and second windings to control a pulse width modulation control circuit such that pulse width modulated control signals are provided to the motor drive circuit only when the voltage across the first and second windings are at a predetermined level.

Abstract: An integrated control and power driving system moves a read/write head carrying arm over the surface of a disk. The integrated control and power driving system is applicable to a spindle motor, a mass storage disk drive and a voice-coil motor, for example, and includes a first chip and a second chip. The first chip integrates the output power stages driving the motors, and has an interface for outputting feedback signals representing functioning conditions of the voice-coil motor and of the spindle motor, and for receiving digital control signals of the output power stages. The second chip integrates logic drive and control circuitries of the power stages and an interface for receiving the feedback signals output by the first chip, and for transmitting to the first chip the digital control signals.

Abstract: An apparatus includes a multi-phase inverter, a fault detector to indicate a detection of a fault, a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed, and a controller. The controller is operable to apply either an open-circuit response or a short-circuit response to the multi-phase inverter. The open-circuit response is applied when the speed of the PM motor is greater less than the transition speed and a fault is detected. The short-circuit response is applied when the speed of the PM motor is less greater than the transition speed and the fault is detected. The transition speed is either a fixed predetermined speed or an adjusted predetermined speed.