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 control circuit includes a first switch element, a second switch element, and a fan connector. A first control terminal of the first switch element is connected to a fan control terminal to receive a pulse width modulation signal. A first terminal of the first switch element is connected to a first voltage source. A second control terminal of the second switch element is connected to the first terminal of the first switch element. A fourth terminal of the second switch is connected to a second voltage source via a NTC resistor. A first pin of the fan connector is connected to ground. A second pin of the fan connector is connected to a third terminal of the second switch element. A third pin of the fan connector is connected to a signal receiving terminal. The third pin is configured to receive a feedback signal indicating a rotating speeding of the fan.

Abstract: An electric power tool is provided that includes a motor as a driving source, a first operation switch, a first semiconductor switch, and a second semiconductor switch. The first operation switch is operated by a user to be turned ON/OFF. The first semiconductor switch, provided on a current path from the power source to the motor, includes at least one semiconductor switching device. When the first operation switch is OFF, the first semiconductor switch is turned OFF to interrupt the current path. When the first operation switch is ON, the first semiconductor switch is turned ON to close the current path. The second semiconductor switch is provided on the current path in series with the first semiconductor switch and includes at least one semiconductor switching device. The second semiconductor switch closes/interrupts the current path by being turned ON/OFF in accordance with an input control signal.

Abstract: The circuit structured to drive a motor is provided. The circuit includes: a division signal generator that generates a division signal dividing each of a high level period and a low level period of a binary position signal representing a relative position of a magnetic coil to a permanent magnet into a preset number of multiple divisions; a pulse width setter that sets a pulse width for PWM control corresponding to each of the multiple divisions represented by the division signal; and a PWM signal generator that performs PWM control with the set pulse width, thereby generating a PWM signal as a driving signal for driving the motor.

Abstract: A fan controlling circuit is provided. The fan controlling circuit includes an integral unit, an operational amplifier, a PMOS transistor, and an NMOS transistor. The integral unit transforms pulse width modulation (PWM) signals to voltages, and transmits the voltages to positive and negative input terminals of the operational amplifier. The PMOS transistor is coupled between a first PWM signal and an output terminal, and a gate of the PMOS transistor is coupled to an output of the operational amplifier. The NMOS transistor is coupled between a second PWM signal and the output terminal, and a gate of the NMOS transistor is coupled to the output of the operational amplifier. The fan controlling circuit may be formed by discrete elements and use a same voltage source as fans, so that the design cost and complexity are reduced.

Abstract: In an embodiment, an integrated circuit includes an input configured to receive a first control signal and an output module configured to generate an output signal based at least on the first control signal and a second control signal generated based at least on a measured temperature of the IC. The output signal is configured to control a cooling device.

Abstract: A voltage regulator for a pair of electric motors has an input for a signal indicative of the desired speed for the motors and a pulse width modulation control circuit device. A control module provides a conditioning signal to the control circuit to output to the motors a square wave voltage having a duty-cycle which varies according to a predetermined function of the signal applied to the input of the regulator. The control circuit device has first and second electronic solid state switches associated with the motor and controlled by the control module.

Abstract: A fan circuit controls a speed of a fan. A control chip outputs a pulse width modulation (PWM) signal that changes with the temperature of an electronic device that the fan is mounted in. An input circuit converts the PWM signal into a continual voltage signal. An amplifier circuit amplifies the voltage signal and outputs a control signal. When the control signal is less than a threshold voltage, the control circuit is turned on and the fan receives current which is less than preset current. When the control signal is greater than the threshold voltage, the control circuit is turned off and the fan receives current which is greater than the preset current.

Abstract: An information handling system includes a three phase brushless direct current motor and a motherboard which in turn includes a drive circuit. The three phase brushless direct current motor is configured to rotate a cooling fan in the information handling system based on a control signal. The drive circuit is connected to the three phase brushless direct current motor, and the drive circuit is configured to adjust the control signal sent to the three phase brushless direct current motor based on a back electromagnetic flux signal.

Abstract: A fan controlling circuit is provided. The fan controlling circuit includes an integral unit, an operational amplifier, and an output unit. The integral unit transforms pulse width modulation signals to voltages, and then the output unit outputs one of the pulse width modulation signals having a higher operation frequency according to the comparison result between the voltages. As the fan controlling circuit may be constituted with discrete elements and use a same voltage source as fans, the design cost and complexity are reduced.

Abstract: A dual-speed single-phase AC motor, including: a stator, including a stator core, and a coil winding, including a starting winding, a first main winding, and a second main winding, a rotor, and a starting circuit, including a rectifying and voltage-stabilizing circuit, a detecting circuit, a voltage comparison circuit, a first switching circuit, a second switching circuit, and a third switching circuit. The number of poles of the starting winding is the same as that of the first main winding. The number of poles of the first main winding is less than that of the second main winding.

Abstract: A DC motor is provided. The DC motor prevents rush or overload of current in the DC motor during and/or after power input irregularities to the DC motor. A control circuit of the DC motor is configured to control current provided to the DC motor. When power irregularities in the power input to the DC motor are detected by the control circuit, the control circuit stops generating PWM (Pulse Width Modulated) signals and stops the current provided to the DC motor. After the stoppage of PWM signals, the control circuit can perform a soft-start of the PWM signals when the power irregularities are no longer detected. The soft starting of the PWM signals generates gradual increase in current to the DC motor, thus, preventing sudden rush of current that cause malfunction of the DC motor.

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: A circuit for controlling a rotation speed of a computer fan includes a control chip, a conversion circuit, a fan header, a first switch, and a second switch. When a first terminal of the first switch is connected to a second terminal of the first switch, and a first terminal of the second switch is connected to a second terminal of the second switch, the conversion circuit converts a control signal received from the control chip to a voltage signal, and outputs the voltage signal to a power pin of the fan header. When the first terminal of the first switch is connected to a third terminal of the first switch, and the first terminal of the second switch is connected to a third terminal of the second switch, a control pin of the fan header receives the control signal, the power pin receives power from a first power supply.

Abstract: When the bit number of an error signal ERR2 is n and the magnitude of the error signal ERR2 is “a” (a is an integer) in decimal notation, a pulse-width modulator generates a PWM signal Spwm as a set of k (k is an integer of 2 or more) continuous sub-pulses. Further, the pulse-width modulator generates k sub-pulses in such a manner that the average value of the duty ratios of the sub-pulses becomes approximately a/2n.

Abstract: A method for controlling an electric motor by using the PWM technique including the steps of: applying to the clamps of the electric motor an electric voltage varying in time, which displays a square waveform and consists of a sequence of pulses having a uniform wave period and a variable width; adjusting the average value of the electric voltage by varying the width of the pulses; determining the overall required width variation; subdividing the overall required width variation in a determined number of partial variations, the overall sum of which is equivalent to the overall required width variation; and gradually varying the width amplitude of the pulses of the electric voltage by applying in a sequence a corresponding partial variation to each pulse, so that the difference between the width amplitude of a pulse and the width of a following pulse is equivalent to the corresponding partial variation.

Abstract: An electric power tool is provided that includes a motor as a driving source, a first operation switch, a first semiconductor switch, and a second semiconductor switch. The first operation switch is operated by a user to be turned ON/OFF. The first semiconductor switch, provided on a current path from the power source to the motor, includes at least one semiconductor switching device. When the first operation switch is OFF, the first semiconductor switch is turned OFF to interrupt the current path. When the first operation switch is ON, the first semiconductor switch is turned ON to close the current path. The second semiconductor switch is provided on the current path in series with the first semiconductor switch and includes at least one semiconductor switching device. The second semiconductor switch closes/interrupts the current path by being turned ON/OFF in accordance with an input control signal.

Abstract: A system for controlling the fan speed is described. Specifically, one embodiment of the present invention set forth a computing system, which includes a first processing unit including a first sensor, wherein the first processing unit is configured to generate a first pulse-width modulation signal, and a first transmission line further including a first direct current voltage converter configured to convert the first pulse-width modulation signal to a first direct current voltage and a first diode coupled to the first direct current voltage converter, wherein the first diode determines whether the first direct current voltage passes through the first diode. The computing system further includes an amplifier coupled to the first diode, wherein the amplifier is configured to amplify a selected direct current voltage to drive a fan.

Abstract: Circuitry for controlling a motor, such as a brushless motor (BLM), is disclosed. The circuitry may comprise one or more inputs for receiving rotor position signals from one or more Hall effect sensors that detect the position of, for example, a BLM rotor. The circuitry may also comprise an input for receiving a pulse width modulated speed control signal. The circuitry generates one or more drive signals, each drive signal having a plurality of driving intervals. Each drive signal may control power switches during its driving intervals, the power switches being coupled to electromagnets of the BLM. The circuitry may cause the driving intervals of a first drive signal to be temporally spaced from the driving intervals of a second drive signal.

Abstract: A system can control a rotary speed of a computer fan according to the type of the computer fan. If the computer fan is determined to be a 3-pin fan, the system can output a changeable voltage to control the rotary speed of the 3-pin fan.

Abstract: A trigger mechanism for starting current acquisition for motor control applications is disclosed. The present invention may generate an edge (ADC trigger) that can be used to start current acquisition by the ADC. The present invention may reduce the overhead involved in synchronizing the current acquisition with PWM generation and also minimize the wait period for software conversions to complete by replacing software-based timing with a hardware-based trigger mechanism.

Abstract: A rotation detecting apparatus for detecting a rotational state of a direct-current motor includes a driving device, a control device, an energization detecting device, an alternating-current component detecting device, and a rotational state detecting device. An impedance between brushes of the motor changes periodically in accordance with rotation of the motor. The alternating-current component detecting device detects change of an alternating-current component of electric current that is supplied to the motor based on an electrical quantity. The change of the alternating-current component is caused by change of the impedance caused in accordance with the rotation. The rotational state detecting device detects at least one of a rotation angle, a rotational direction, and a rotational speed of the motor based on a detection result of the alternating-current component detecting device.

Abstract: A motor and a motor speed control system are disclosed. Two power signal lines and one feedback/speed-control signal line are coupled between a control device and the motor. The two power signal lines electrically connect the control device to the motor. The feedback/speed-control signal line bi-directionally transmits signals coming from the control device to the motor and from the motor to the control device.

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: The invention concerns an electronic module for a motor vehicle, in particular a fan regulator (4?) with a control input (S) for a signal, in particular a pulse width modulated signal, transmitted via a signal line (3). The electronic module is designed for the generation of an essentially constant potential (Ubias, Ubias?UBE) at the control input (S), which preferably is designed as a current-controlled, low resistance control input. The invention also concerns an arrangement (1?) for the transmission of a preferably pulse width modulated signal with: a control device (2?) for the generation of the signal, a signal line for the transmission of the signal, and an electronic module as described above.

Abstract: A method for controlling a heat-dissipating fan for an electronic component includes the steps of: detecting a temperature of the electronic component, and outputting a first control signal corresponding to the temperature thus detected; receiving a load current of the electronic component, and converting the load current into a second control signal; and controlling a rotating speed of the heat-dissipating fan with reference to the first control signal and the second control signal. A device employing the method includes a current detecting module adapted for detecting a load current, a temperature control circuit adapted for detecting a temperature, and a logic circuit unit coupled to the current detecting module and the temperature control circuit and controlling a rotating speed of a heat-dissipating fan.

Abstract: A motor speed control system includes a pulse outputting device capable of outputting a pulse each time a motor rotates, a pulse interval determining device capable of determining a pulse interval between the pulses outputted, and a comparative value calculating device capable of obtaining a comparative value as the product of a first value and a second value. The first value can correspond to the pulse interval determined, and the second value can correspond to a set rotational speed of the motor. The system can further include a set value calculating device capable of obtaining a set value as the product of the second value and a third value and a controller capable of controlling a supply of power to the motor such that a difference between the set value and the comparative value decreases.

Abstract: If a PWM duty instruction D1 determined by a duty calculation circuit exceeds an upper limit value, a duty signal processing circuit in a motor drive apparatus divides a switching current supply period in each of the phases into a first current supply period and a second current supply period. In the first current supply period, the duty is set to the upper limit value. In the second current supply period, the duty is set to 100%, and the length of the second current supply period is set depending upon the duty instruction.

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: A driving device is provided for controlling rotation of a motor. The driving device comprises an inputting module, a comparing module and a processing module. The inputting module includes a first current source, a first voltage source and a first capacitance. The first capacitance is coupled between the first current source and the first voltage source for charging/discharging and generating a voltage signal. The comparing module is coupled to the inputting module for comparing a selecting signal with the voltage signal and generating a comparing signal. The processing module is coupled to the comparing module and generates a control signal according to a clock signal and the comparing signal, wherein the driving device controls the rotation of the motor by the control signal.

Abstract: The circuit structured to drive a motor is provided. The circuit includes: a division signal generator that generates a division signal dividing each of a high level period and a low level period of a binary position signal representing a relative position of a magnetic coil to a permanent magnet into a preset number of multiple divisions; a pulse width setter that sets a pulse width for PWM control corresponding to each of the multiple divisions represented by the division signal; and a PWM signal generator that performs PWM control with the set pulse width, thereby generating a PWM signal as a driving signal for driving the motor.

Abstract: An electronic switch for controlling a motor. The switch includes at least one deflectable resistor including a substrate having a first configuration. The substrate being bendable to a second configuration relative to the first configuration. A layer of conductive material is disposed on a surface of the substrate, wherein the layer of conductive material having a resistance that changes predictably when an electrical signal is applied thereto. The change of resistance of the layer of conductive material reflects an amount of deflection between the first configuration and the second configuration and for various configurations in between. A motor assembly is coupled to the at least one deflectable resistor. The deflectable resistor, when positioned in the first configuration turns off the motor assembly. Also, the deflectable resistor when bent towards the second configuration and away from the first configuration turns on the motor assembly.

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 two-stranded electronically commutated DC motor has a permanent-magnet rotor (36), power supply terminals (28, 30) for connecting the motor to a current source (22) and a stator (102) having a winding arrangement which includes first and second winding strands (52, 54). The latter are controlled by respective first and second semiconductor switches (70, 80). The motor also has a third controllable semiconductor switch (50), arranged in a supply lead from one of the terminals (28, 30) to the winding strands (52, 54), which third switch is alternately switched on and off by applying to it a PWM (Pulse Width Modulated) signal 24. During switch-off intervals, magnetic flux energy stored in the motor causes a decaying loop current (i2) to run through the windings, continuing to drive the rotor. This facilitates conformal mapping of temperature information in the PWM signal onto a target motor rotation speed.

Abstract: A motor control apparatus that controls a DC motor includes a detection unit configured to detect angular speed of the DC motor, a driven member configured to be driven by the DC motor, and a control unit configured to increase, when starting to drive the DC motor, a control value for controlling driving of the DC motor from a first control value to a second control value at a predetermined increase rate, wherein the control unit detects a start-up characteristic of the DC motor based on a detection result of the detection unit, and corrects the first control value or the increase rate according to a result of comparing a detected start-up characteristic and a predetermined start-up characteristic such that the start-up characteristic of the DC motor becomes closer to the predetermined start-up characteristic.

Abstract: A method and circuit enabling off-the-shelf controllers designed for use with a two-level AC drive inverter bridge (1920) to drive inverter bridges with three-or-more levels. Signals from an ordinary induction motor controller or a two-level induction motor controller (2200) are used to drive the twelve-or-more switches of a three-or-more level inverter bridge (1920), as are used in medium-and-high voltage applications. The proper sequence and timing of switching for the three-or-more-level inverter bridge is based in-part upon either the output of the six pulse-width modulators, or the output of the flux and torque control device, or the voltage control device (2210), of the two-level controller (2200).

Abstract: A method and apparatus are disclosed for determining a negative pressure generated by a suction pump of a topical negative pressure (TNP) system. The method includes the steps of disconnecting a drive voltage from a pump of the TNP system, determining an EMF generated by a free-wheeling element of the pump, selecting a new drive voltage for the pump and reconnecting the new drive voltage to the pump.

Abstract: A driving apparatus for fan motors, electrically connected between a pulse width modulation (PWM) signal generator and a controller, includes a converter electrically connected to the PWM signal generator, generating a first reference voltage according to the duty cycle of a PWM signal generated by the PWM signal generator; a reference voltage generator electrically connected to an external power source, generating a second reference voltage according to the external power source; and a comparator having a first and second input terminal and an output terminal; wherein the first input terminal is electrically connected to the converter, the second input terminal is connected to the reference voltage generator and the output terminal is connected to the controller, and when the first reference voltage is greater than the second reference voltage, a driving signal is output from the output terminal to the controller to control the rotation speed of the fan motor.

Abstract: A method and a device for controlling and/or regulating an electric motor. Such electric motors are used for example in motor vehicles in the form of pump motors. In general, the electric motor is supplied with electrical energy from a battery and/or using a generator. The controlling and regulation take place using a high-frequency pulse width modulation (PWM). When the electric motor is started, the PWM is used to continuously increase the motor current required for the operation of the electric motor, e.g. beginning from 0.

Abstract: Circuitry for controlling motors, such as a brushless motor (BLM), is disclosed. The circuitry may comprise one or more inputs for receiving rotor position signals from one or more Hall effect sensors that detect the position of, for example, a BLM rotor. The circuitry may also comprise an input for receiving a pulse width modulated speed control signal. The circuitry generates one or more drive signals, each of which may comprise a logical combination (e.g., a logical AND combination) of the speed control signal and a rotor position signal, for controlling power switches that are coupled to electromagnets of the BLM.

Abstract: The present invention discloses a control system for controlling a motor for a heating, ventilation and air conditioning (HVAC) or a pump comprising: an opto-isolated speed command signal processing interface into which a signal for controlling a speed of the motor is inputted and which outputs an output signal for controlling the speed of the motor being transformed as having a specific single frequency; a communication device into which a plurality of operation control commands of the motor; an opto-isolated interface for isolating the plurality of operation control commands inputted through the communication device and the transformed output signal for controlling the speed of the motor, respectively; a microprocessor, being connected to the opto-isolated interface, for outputting an output signal for controlling an operation of the motor depending on the plurality of operation control commands and the transformed output signal for controlling the speed of the motor; a sensor, being connected to the motor,

Abstract: A drive circuit of a fan motor is provided. In an embodiment of the drive circuit, a first PWM comparator compares a temperature detection voltage with a cyclic voltage, and outputs a first PWM signal. A second PWM comparator compares a minimum frequency setting voltage indicating a minimum frequency of the fan motor, with the cyclic voltage, and outputs a second PWM signal. The drive circuit combines the first PWM signal and the second PWM signal by a logical operation, to drive the fan motor. The drive circuit includes a first logic gate which generates a logical sum of the first PWM signal and the second PWM signal, and a second logic gate which generates a logical product of the first PWM signal and an inverted signal of the second PWM signal. The drive circuit switches drive mode based on the first logic gate and the second logic gate.

Abstract: The invention relates to a method for measuring a current that flows through a motor, in which a power switch that supplies the motor with electric energy is controlled by a control unit via a pulse width-modulation signal. The pulse width-modulation signal comprises a cycle of operation and the motor current is determined in a feeder to the power switch or a feeder to the motor. Since exactly one measured value representing the motor current is sampled in each cycle of operation, this permits the provision of a method for measuring the motor current, which determines the motor current in a more rapid, more cost-effective manner than in prior art. The method is used for the motor control of direct current motors.

Abstract: Provided are a method, computer-readable medium, and system for automatically determining a proper operational current input to an electric motor. In an exemplary embodiment, a method for determining the proper operational current input includes sending a test signal to an input of an electric motor. A response to the test signal is measured using an output of the electric motor. Based on the measured response, a position of a brush that is capable of conducting current through a commutator of the electric motor is determined. The electric motor is supplied with a first current input if the brush is in a first position and a second current input if the brush is in a second position.

Abstract: A motor control apparatus for controlling a DC motor includes a detection unit configured to detect an angular speed of the DC motor, and a control unit configured to, when the DC motor is accelerated, increase a control value that controls a driving of the DC motor at a constant rate from a first control value corresponding to an angular speed lower than a target angular speed up to a second control value corresponding to an angular speed higher than the target angular speed, and switch the control value that controls the driving of the DC motor to a control value corresponding to the target angular speed in response to the detection result of the detection unit reaching the target angular speed.

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: A motor drive device of the present invention includes: an output circuit provided with a switch element connected to a motor; a PWM signal generating circuit for generating a PWM signal having a duty corresponding to a ratio between a power supply voltage applied to the motor and a predetermined control voltage; a control circuit for performing on/off control of the switch element according to the PWM signal; and a control voltage generating circuit for generating the control voltage such that the back electromotive voltage of the motor is maintained at a desired value.

Abstract: An exemplary method for controlling rotation speed of a computer fan includes: judging the type of a fan by comparing two rotation speeds detected before and after changing a duty cycle of a PWM signal respectively; controlling the computer fan as a 4-pin fan the PWM signals if the rotation speeds are different; and controlling the computer fan as a 3-pin fan via voltage signals converted from the PWM signals if the rotation speeds are equal. And an exemplary circuit for controlling rotation speed of a computer fan is capable of controlling rotation speed of the 4-pin fan via PWM signals, and controlling rotation peed of the 3-pin fan via voltage signals converted from PWM signals.

Abstract: A motor drive device comprising an H-bridge circuit having four switching elements connected in an H bridge form to a motor coil L, a control circuit for on-off controlling each switching element, and a PWM signal generating circuit for generating a PWM signal having a duty according to a ration between a power supply voltage Vcc and a control voltage Vref, wherein the control circuit is so constituted as to select a switching element to be turned on according to an operation mode control signal FIN, RIN and control its on-duty according to the PWM signal. This constitution can variably control easily and over a wide range a drive voltage applied to one end of the motor coil L according to an externally input control voltage Vref.

Abstract: In one aspect, a control circuit to control a speed of a motor includes a control logic circuit connected to a multifunction port. The control logic circuit is configured to receive a control signal provided at the multifunction port and to provide response signals based on the control signal to place the motor in at least two of a sleep mode, a brake mode and a pulse-width modulation (PWM) mode. The motor control circuit also includes an H-bridge circuit configured to control the motor based on the response signals.