National Cheng-kung University

Wei-Ching Tseng

Tsorng-Juu Liang

Jiann-Fuh Chen

Yi-Chuan Tsai

An LED driver circuit includes: a bridge rectifier, a first compensation capacitor, a second compensation capacitor, and an LED module. The bridge rectifier is connected to an AC input power for producing a rectification output power. The first compensation capacitor is connected to a first rectification output terminal and an AC input terminal of the bridge rectifier. The second compensation capacitor is connected to a second rectification terminal and the AC input terminal of the bridge rectifier. The LED module is connected to the first rectification output terminal and the second rectification output terminal of the bridge rectifier. The first and second compensation capacitors in the present invention can effectively improve the total current harmonic distortion of the LED module and its utilization.

LED driver circuit

An LED driving device includes a rectifier circuit, a first LED module, a first switch, a second LED module, a second switch, and a diode module. The rectifier circuit includes a pair of input terminals and first and second output terminals for receiving an AC voltage and rectifying the AC voltage to output a pulsed rectified voltage. The first LED module and first switch connected in series are electrically connected between the first and second output terminals of the rectifier circuit. The second LED module and second switch connected in series are electrically connected between the first and second output terminals of the rectifier circuit. The diode module is connected between a common node of the first LED module and the first switch and a common node of the second LED module and the second switch.

LED driving device

An LED driving device includes: an LED circuit having an input side for receiving a driving current corresponding to an AC input voltage from an external power source when the magnitude of a driving voltage across the input side is greater than a predetermined value; and a clamp circuit coupled between the input side of the LED circuit and the external power source, and permitting the driving current to pass through for clamping the magnitude of the driving current to a predetermined current level and for clamping the magnitude of the driving voltage to a predetermined voltage level.

Growing community of inventors

Kaohsiung, Taiwan

Wei-Ching Tseng