Unity Opto Technology Co., Ltd.

Shao-Wei Chiu

Chih-Hsien Wu

Wei Chang

Kai-Cheng Chuang

Huan-Ying Lu

Cheng-Han Hung

A self-excited TRIAC dimming circuit applied in a panel light includes a dimming module and at least one conversion module, and a power factor controller (PFC) is installed in the dimming module, and the conversion module is a self-excited electronic isolation transformer, and the TRIAC PFC is integrated with the circuit structure of a self-excited electronic transformer to improve the overall circuit stability, so that the panel light complies with a high safety standard to enhance product applicability and competitiveness.

Self-excited TRIAC dimming circuit

An LED driver circuit for supplying a TRIAC holding current by using a controllable current source has a single-stage power factor correction circuit architecture, and the circuit receives an input voltage received by a conversion module of the controllable current source to form an operating current for driving an LED light source to emit light and monitoring the change of the input voltage by a control chip, and adopts a switching method of a fixed cut-off time of a switch unit, so that the controllable current source outputs a constant operating current in a standard peak value to achieve the constant current status during the operation of the LED light source while assuring the operating current is always greater than a holding current required by the TRIAC element when the TRIAC element is conducted.

LED driver circuit for supplying TRIAC holding current by using controllable current source

An LED driving device with open circuit protection and color temperature and brightness adjustment is applied in a lamp to drive LEDs which are divided into strings, and at least one string is formed by connecting blue light diodes in series, and the remaining strings are formed by connecting yellow light LEDs in series, and at least one of the yellow light strings is connected to the blue light string in parallel and then connected to the remaining strings in series to form a node. The LED driving device employs a switch to conduct the blue or yellow light string to change the color temperature of the emitted light of the lamp, and a power input pin of a control chip is electrically coupled to the node. If there is an open circuit caused by an abnormality of the LEDs, the operation will be stopped to provide protection.

LED driving device with open circuit protection and color temperature and brightness adjustment

A ceiling lamp adopting a non-separating driver circuit includes a conversion module and a control module. The conversion module converts an input voltage into an operating voltage to drive the LEDs and forming a driving current, and the control module monitors the operating voltage and the driving current to adjust the operating cycle of the conversion module, change the output voltage value of the operating voltage, and linearly change the driving current at a constant current state. The conversion module just executes the power conversion for one time to provide the driving power of the LEDs instead of using the conventional driving method that executes a two-stage power conversion by a separating power converter and a negative booster of the conventional ceiling lamp. Therefore, the ceiling lamp adopting a non-separating driver circuit is capable of lowering the circuit cost and improving the operating efficiency.

Ceiling lamp adopting non-separating driver circuit

Disclosed is a variable power dimming control circuit for driving and linearly adjusting the illumination brightness of a plurality of light emitting diodes (LEDs), and the circuit includes a dimming stabilization unit and a control unit. The control unit is provided for detecting an input current of a circuit, and the dimming stabilization unit is driven for outputting a holding current when the input power is smaller than a standard, and stopping the output the holding current when the input power is greater than the standard. When the LEDs are dimmed to low luminance, a chip controls the operation of the dimming stabilization unit to assure the stability of the dimming operation of a TRIAC. When the LEDs are adjusted to high or full brightness, the chip stops the output of the holding current to reduce unnecessary power consumption and enhance the overall circuit performance effectively.

Variable power dimming control circuit

An adaptive LED dimming driving circuit is disclosed, wherein its control module is disposed with a first resistor, a second resistor, a retainer, a third resistor and a fourth resistor. When the control module receives an input voltage, the retainer is driven to output a retaining current Ito the second resistor, thereby ensuring normal dimming. The first resistor and the third resistor detect the input voltage so that when an input current Isatisfies a correlation I=I+I, the retaining current has the minimum value to increase work efficiency during the LED that is dimmed to the maximum intensity. When the input voltage is too low, the reference level is reduced to prevent the LED from generating twinkling. The fourth resistor detects the voltage energy of the LED. Therefore, when the voltage energy is changed, a high-low-voltage compensation is performed to achieve a constant power state.

Growing community of inventors

Taipei, Taiwan

Shao-Wei Chiu