System General Corporation

Richtek Technology Corporation

Fairchild Semiconductor Corporation

Shih-Jen Yang

Hung-Sen Tu

Ta-Yung Yang

I-Hsing Chen

Chen-Chia Yang

Pei-Sheng Tsu

Yi-Min Hsu

Chung-Hui Yeh

Yi-Min Shiu

Yi-Chi Lin

Chung-En Chen

Wei-Hsu Chang

Yi-Wei Lee

Chao-Chi Chen

I-Chi Lin

Chang-Yi Lin

Ming-Hsuan Lee

Jian Chang

Yung-Sheng Wu

Wen-Chang Lu

Chih-Ping Yin

Chen-Cha Yang

Ming-Wei Cheng

Shin-Li Lin

He-Yi Shu

Yu-Chieh Hsieh

Chih-Ching Lee

Yi-Shan Chu

Ta-Hsu Huang

A method for predicting failure of a cooling fan includes driving a motor of the cooling fan based on a control speed, generating a first speed according to an average speed of the motor, generating a first current according to an average current of the motor, retrieving a system coefficient from a memory, generating a current threshold according to the first speed and the system coefficient, and triggering an alarm signal if the first current exceeds the current threshold by a threshold amount.

Method and system for failure predication of cooling fan

A flyback power converter includes a power transformer, a first lossless voltage conversion circuit, a first low-dropout linear regulator and a secondary side power supply circuit. The first low-dropout linear regulator (LDO) generates a first operation voltage as power supply for being supplied to a sub-operation circuit. The secondary side power supply circuit includes a second lossless voltage conversion circuit and a second LDO. The second LDO generates a second operation voltage. The first operation voltage and the second operation voltage are shunted to a common node. When a first lossless conversion voltage is greater than a first threshold voltage, the second LDO is enabled to generate the second operation voltage to replace the first operation voltage as power supply supplied to the sub-operation circuit; wherein the second lossless conversion voltage is lower than the first lossless switching voltage.

Flyback power converter and secondary side power supply circuit and control method thereof

A multiple output universal serial bus travel adaptor includes: at least one AC-DC converter for converting an AC power to a first DC power; at least one DC-DC converter for providing a second DC power according to the first DC power; plural switches which are coupled to the AC-DC converter and/or the DC-DC converter to provide the first DC power or the second DC power to corresponding connectors according to operation signals; and a protocol controller configured to generate the operation signals according to at least one of the following parameters: a) the types of the connectors; b) whether there is a mobile device connected with the connectors; c) a first command from the mobile device; d) the power consumed by the mobile devices; e) the currents flowing through the connectors; and f) the voltages at the connectors.

Multiple outputs universal serial bus travel adaptor and control method thereof

An abnormal connection detection method is used between a power supplier and a power receiver. The power supplier and the power receiver are connected through a cable. The cable includes positive and negative power transmission lines. The abnormal connection detection method includes: providing an output voltage from the power supplier, wherein the output voltage is lower than a predetermined voltage threshold; detecting, according to the output voltage, whether an output current generated by the power supplier is higher than a predetermined current threshold; and when the output current is higher than the predetermined current threshold, determining that an abnormal connection occurs between the power supplier and the power receiver.

Abnormal connection detection method

A back electromotive force (EMF) detector for a motor is disclosed. The back EMF detector includes an upper switch, a lower switch, a current sensing resistor and a first to third resistance providers. The upper and lower switches are controlled by a first and a second control signal respectively. The current sensing resistor coupled between the lower switch and a reference ground voltage. A first terminal of the first resistance provider coupled to the upper switch, and a back EMF detection result is generated at a second terminal of the first resistance provider. The second resistance provider coupled between the reference ground voltage and the first resistance provider. The third resistance provider is coupled between the coupled terminal of the first and second resistance provider and the lower switch. Wherein, the first to the third resistance providers are determined by at least one characteristic parameter of the motor.

Sensorless motor apparatus, back EMF detector and detection method thereof

A sensor fastening method and a sensor fastening frame for use therewith are provided. The sensor fastening frame is coupled to a motor stator of a brushless motor having distributed coils and extends over the distributed coils to allow the sensor fastening frame to rotate about the axle of a motor rotor, without interference with the distributed coils. At least a sensor is fastened in position to the sensor fastening frame proximate to one end of the axle of the motor stator for positioning the sensor to detect magnetic field variations of the motor rotor.

Sensor fastening method and sensor fastening frame for use therewith

An end cover adapted to engage with an end surface of a spindle of a motor rotor is proposed for securely coupling to the spindle with a plurality of permanent magnets disposed around the peripheral wall of the spindle. The end cover has a first surface facing an end surface of the spindle and an second surface opposing to the first surface, which is formed with a plurality of inserting slots indentedly disposed around the rim thereof and corresponding to the permanent magnets for coupling the ends of the permanent magnets, thereby securely fastening each of the permanent magnets to the spindle of the motor rotor. Further, the present invention further provides a motor rotor having the end covers described above.

End cover and motor rotor having the end cover

A speed-control circuit for a BLDC motor is provided. The speed-control circuit includes a pulse generator, a current source circuit, a filter circuit, an error amplification circuit and a PWM circuit. The pulse generator detects a speed signal of the BLDC motor to generate a pulse signal. The filter circuit is coupled to the current source circuit to generate an average signal. The error amplification circuit receives the average signal and a speed-reference signal for generating a speed-control signal. The PWM circuit generates a switching signal to drive the BLDC motor in response to the speed-control signal. A pulse width of the switching signal is determined by the speed-control signal.

Constant-speed control circuit for BLDC motors

A motor rotor includes an annular body and a plurality of magnetic bodies installed on an inner lateral surface of the annular body in an irregular manner, to prevent a rotating motor from generating a cogging effect, disperse the frequency of the cogging torque, and reduce the amplitude. Accordingly, noises generated while the motor is operating are reduced, the periodicity of a cogging torque is changed, and cogging torque is reduced.

Motor rotor and a motor having the same

A dual-switch flyback power converter includes a control circuit to generate a switching signal. A high-side driving circuit includes a pulse generation circuit. The pulse generation circuit generates a pulse-on signal and a pulse-off signal to control two transistors in response to the switching signal. The two transistors further respectively provide a level-shift-on signal and a level-shift-off signal to a comparison circuit to enable/disable a high-side driving signal. Without using a charge pump circuit to power the high-side driving circuit, a floating winding of a transformer is utilized to provide a floating voltage to power the high-side driving circuit, which reduces the cost of the dual-switch flyback power converter and ensures a sufficient high-side driving capability of the high-side driving circuit.

Flyback power converters having a high side driving circuit

A power management interface is provided and includes a switch, a transmitting circuit, and a receiving circuit. The switch is coupled to an AC power line for controlling a power line signal to a load. The transmitting circuit generates a switching signal to control the switch and achieve a phase modulation to the power line signal in response to a transmitting-data. The receiving circuit is coupled to receive the power line signal for detecting a phase of the power line signal and generating a receiving-data to control power of the load. The receiving-data is generated in accordance with the phase detection of the power line signal and correlated to the transmitting-data.

Power management interface

A BLDC (brushless direct current) motor system of the present invention includes a control circuit, a sequencer, a driving circuit, and a BLDC motor. The control circuit determines the maximum torque and the maximum speed of the BLDC motor. The control circuit includes an over-current detection circuit to generate a reset signal in response to a switching current of the BLDC motor. The reset signal is generated when the switching current of the BLDC motor exceeds a threshold. A pulse width of the PWM signal is correlated to the level of a speed-control signal and the level of the torque-control signal. The pulse width of the PWM signal is also controlled by the reset signal generated by the over-current detection circuit.

Control circuit for BLDC motors

A BLDC (brushless direct current) motor system of the present invention includes a control circuit, a sequencer, a driving circuit, and a BLDC motor. The control circuit comprises a speed-feedback loop and a torque-feedback loop to control the maximum speed and the maximum torque of the BLDC motor in parallel configuration. The speed-feedback loop generates a speed-control signal. The torque-feedback loop generates a torque-control signal. A PWM circuit receives the speed-control signal and the torque-control signal to generate a PWM signal. A pulse width of the PWM signal is correlated to the level of the speed-control signal and/or the level of the torque-control signal.

Control circuit with dual programmable feedback loops for BLDC motors

A mounting structure for fixing an electronic element on a heat dissipation unit is provided. The mounting structure includes a heat dissipation unit, a fixing member, electronic elements and elastic elements. The fixing member is fixed on the heat dissipation unit. The elastic elements are sandwiched between the electronic elements and the fixing member, wherein the fixing member and the elastic elements press the electronic elements to make the electronic elements tightly contact the heat dissipation unit.

Mounting structure for an electronic element

A rotating shaft disclosed by the present invention includes a plurality of bumps spacedly formed along an outer circumferential surface thereof. The bumps are each formed with two engagement portions extending outwardly and bilaterally and a deformation space therebetween. The engagement portions undergo resilient deformation toward the deformation space when subjected to a force, thus providing stable engagement with a magnetic body, protecting the magnetic body from cracks and damages during assembling, and enhancing yield. The present invention further discloses a motor rotor having the above-described rotating shaft.

Growing community of inventors

Taipei County, Taiwan

Shih-Jen Yang