Qisda Corporation

Benq Corporation

Acer Peripherals, Inc.

Chi-Jen Chen

Fang-Chieh Lu

Chuan-Chu Chen

Chun-Hsiao Lin

Chih-Hsiang Wu

Ching-Ying Tsou

Tsung-Hsun Wu

Po-Fu Wu

Chun-Ming Shen

Min-Wen Hong

Fu-Shiung Shih

Shih-Pin Chen

Yuan-Ting Fang

Wei-Chun Huang

Chi-Hong Chen

Sung-Po Yeh

Chun-Jung Hu

A light emit diode (LED) driving circuit, an LED driving method and a display device thereof are provided. The LED driving circuit includes: a first LED driving unit for driving first and second color LEDs of the LED circuit. The first LED driving unit includes: a duty cycle circuit generating an enable signal based on at least two color light duty cycle signals, the at least two color light duty cycle signals controlling an emitting cycle of the LED circuit; a current control circuit, generating at least two color light current adjustment signals based the at least two color light duty cycle signals and at least two color light current level signals; and a constant current circuit, for adjusting current levels of the first and the second color LEDs of the LED circuit based on the enable signal and the at least two color light current adjustment signals.

LED driving circuit, LED driving method and display device applying the same

A display device includes a first luminescent device, a second luminescent device, a multi-color strobe decoder, a pseudo signal circuit and a single-color driving circuit. The multi-color strobe decoder is configured to generate two gate control signals. The second luminescent device and the pseudo signal circuit are coupled to the multi-color strobe decoder. The single-color driving circuit is coupled to the first luminescent device and the multi-color strobe decoder. When the single-color driving circuit provides first current for driving the first luminescent device according to the first gate control signal and/or a brightness enhancing signal, the pseudo signal circuit is configured to couple a first bias voltage to the multi-color strobe decoder according to the first gate control signal. When the second gate control signal drives the second luminescent device, the second luminescent device is configure to couple a second bias voltage to the multi-color strobe decoder.

Display device and related driver

A projector and a drive circuit thereof are provided. The projector includes a light source and a drive circuit. The light source includes at least one red light diode, at least one green light diode, at least one first blue light diode and at least one second blue light diode. The drive circuit includes a red light drive circuit, a green light drive circuit, a first blue light drive circuit and a second blue light drive circuit. The green light drive circuit outputs a green light drive signal to the green light diode according to a green light control signal. The second blue light drive circuit outputs a second blue light drive signal to the second blue light diode according to a second blue light control signal. The second blue light control signal and the green light drive signal have synchronous pulse.

Light emitting diode projector and drive circuit thereof

A projector drive circuit includes a first voltage converter, a light source driver, a second voltage converter, and an isolation circuit. The first voltage converter converts a first voltage into a second voltage. The light source driver converts the second voltage into a third voltage. The second voltage converter converts the second voltage into a fourth voltage. The control circuit, coupled to the second voltage converter, receives the fourth voltage and outputs a first control signal. The isolation circuit, coupled to the control circuit and the light source driver, receives the first control signal and generates a second control signal to the light source driver, which controls the light source driver to generate the third voltage and provide the third voltage to a light source according to the second control signal. The isolation circuit electrically isolates the control circuit from the light source driver.

Projector drive circuit, projector drive method and projector

A light intensity adjustment circuit includes a delay circuit, a switching circuit and a light-emitting circuit. The delay circuit includes a capacitor and is used to receive a first pulse width modulation signal and generate a delay signal according to the first pulse width modulation signal. The switching circuit includes a switching unit and an isolation circuit. The switching unit includes a control terminal coupled to the delay circuit and used to receive the delay signal, and a first terminal used to generate a current according to the delay signal. The isolation circuit is coupled to the first terminal of the switching unit and generate a second pulse width modulation signal according to the current. The light-emitting circuit is used to receive the second pulse width modulation signal and emit light accordingly.

Light intensity adjustment circuit

A driver circuit includes a first voltage conversion unit, a second voltage conversion unit, a third voltage conversion unit, a light driver and a control circuit. The first voltage conversion unit may convert a first voltage to a second voltage. The second voltage conversion unit may convert the second voltage to a third voltage in a non-electrically isolated manner. The third voltage conversion unit may convert the second voltage to a fourth voltage in a non-electrically isolated manner. The light driver may receive the third voltage and a control signal to generate a control current according to the control signal. The control circuit may receive the fourth voltage and an image signal to generate the control signal according to the image signal.

Driver circuit and projector including voltage conversion units at primary side

A power control circuit for a projector for controlling a light source of the projector. The power control circuit includes: a detector for detecting an AC input voltage is a first value or a second value; a switch coupled to the detector, conducting or disconnecting of the switch being based on the detector detecting whether the AC input voltage is the first value or the second value, the switch further outputting a first control signal; and a laser driver coupled to the switch and the light source, in response the first control signal from the switch to change power consumption of the light source. When the AC input voltage is the first value, power consumption of the light source is a default value. When the AC input voltage is the second value, power consumption of the light source decreased from the default value.

Projector, power control circuit and method for the same

An electronic device includes a casing, a circuit board, an electronic component and a fixing member. The casing includes a fixing pillar and at least one rib. The rib is connected to a periphery of the fixing pillar. The circuit board includes a through hole. The fixing pillar is disposed in the through hole. The circuit board abuts against a second top surface of the rib. A thickness of the circuit board is smaller than a height between a first top surface of the fixing pillar and the second top surface of the rib. The electronic component includes a first metal member. A first ground end of the first metal member is disposed on the first top surface of the fixing pillar. A gap exists between the first ground end and the circuit board. The fixing member fixes the first ground end to the fixing pillar.

Electronic device

A driver circuit includes a first voltage converter, a light source driver, a second voltage converter and a control circuit. The first voltage converter converts a first voltage to a second voltage. The light source driver is coupled to the first voltage converter, converts the second voltage to a third voltage and outputs the third voltage to a light source for providing light. The second voltage converter is coupled to the first voltage converter, converts the second voltage to a fourth voltage and outputs the fourth voltage. The control circuit is coupled to the second voltage converter to receive the fourth voltage and outputs a first control signal to control the light source driver for controlling the light source. The first voltage is lower than the second voltage, the second voltage is higher than the third voltage, and the second voltage is higher than the fourth voltage.

Driver circuit having light source driver at primary side

An electronic device includes a first light module, a second light module, a primary driver, and a first secondary driver. The first light module is used to emit a first light, and the second light module is used to emit a second light. The primary driver has a first control terminal for turning on the first light module during a first duration, and a second control terminal for turning on the second light module during a second duration. The first secondary driver is used to turn on the first light module during the second duration.

Method for operating an electronic device to increase light density and electronic device thereof

A projector includes an apparatus casing, a light source module, a flow generating device, a sensing module, and a power module. The light source module is disposed inside the apparatus casing and includes a light-emitting part and a lampshade surrounding the light-emitting part. The flow generating device can generate an air flow for dissipating heat by the light source module. The sensing module is disposed in the apparatus casing and includes a thermo-sensitive component disposed near the lampshade and located in a flowing path of the air flow. The power module is disposed in the apparatus casing and electrically connected to the light source module and the sensing module. The power module selectively stops powering the light source module according to an electric parameter of the thermo-sensitive component. Thereby, the invention protects the projector from being overheated by use of the thermo-sensitivity of the thermo-sensitive component.

Projector with a therm-sensitive component for overheating protection

The present invention provides a direct current generator and a pulse generator thereof. The pulse generator includes a comparator to replace a central processing unit and a logic integrated circuit to save the costs and space required by the electronic components. The pulse generator generates pulses to control the activation of the direct current generator and then to control the output current of the direct current generator. The direct current generator generates current having pulses based on pulses signals from the pulse generator to drive a load.

Direct current generator and the pulse generator thereof

An electronic apparatus, AC/DC conversion device and power factor correction circuit are provided. The power factor correction circuit includes an inductance, a switch, a power control chip, a first diode and a first capacitor. The inductance has a first end and a second end. The first end receives a first voltage. The switch has one end coupled to the second end of the inductance and has the other end coupled to a low voltage. The power control chip receives a spread spectrum synchronization signal, and controls turning on/off of the switch by a control signal according to the spread spectrum synchronization signal. The first diode has an anode coupled to the second end of the inductance. The first capacitor has one end coupled to a cathode of the first diode for generating a second voltage and has the other end coupled to the low voltage.

Electronic apparatus, AC/DC conversion device and power factor correction circuit thereof

A power factor correction apparatus with an embedded direct-current to direct-current (DC-DC) converter is provided. The apparatus includes a power factor controller, a high-voltage adapter and a low-voltage adapter. The power factor controller, which receives an AC power source, includes a transformer. The secondary side of the transformer includes a first sub-coil and a second sub-coil for outputting a first power source and a second power source respectively. The high-voltage adapter converts the first power source into a high DC power source. The low-voltage adapter converts the second power source into a first DC power source. The power factor controller corrects the power factor of the power factor correction apparatus according to the first DC power source.

Power factor correction apparatus with embedded DC&#x2014;DC converter

The invention is to provide a projector of external power supply, which comprises: a DC (direct current) power supply port, a step-up circuit, a voltage regulation circuit, a lamp, and an igniter. Wherein, a DC voltage provided from outside is received by the DC power supply port and is converted to a first electric potential by the step-up circuit. The first electric potential may actuate the igniter to light up the lamp and, after the lamp is lighted up, the step-up circuit regulates the working voltage of the lamp to a second potential voltage. Wherein, the first electric potential is higher than the second electric potential.

Growing community of inventors

Taoyuan, Taiwan

Chi-Jen Chen