| US 7,514,882 B2 | ||
| Lamp driving device and method | ||
| Shu-Ming Chang, Hsinhua (Taiwan); Yu-Pei Huang, Hsinhua (Taiwan); Shen-Yao Liang, Hsinhua (Taiwan); and Shwang-Shi Bai, Hsinhua (Taiwan) | ||
| Assigned to Himax Technologies Limited, Tainan County, Taiwan (China) | ||
| Filed on Jul. 13, 2006, as Appl. No. 11/485,896. | ||
| Claims priority of application No. 95100636 A (TW), filed on Jan. 06, 2006. | ||
| Prior Publication US 2007/0159112 A1, Jul. 12, 2007 | ||
| Int. Cl. H05B 37/02 (2006.01) | ||
| U.S. Cl. 315—291 [315/276; 315/307; 315/361; 315/362] | 11 Claims |
| 1. A lamp driving device, comprising:
a pulse width modulation circuit arranged to generate a pulse width modulation signal;
a phase splitter coupled to the pulse width modulation circuit and arranged to split the pulse width modulation signal into
a plurality of phased signals having different phases, wherein pulses of each phased signal are non-overlapping with those
of another phased signal, wherein the phase splitter comprises:
a plurality of flip-flops coupled to the pulse width modulation circuit, and arranged to receive the pulse width modulation
signal and a reset signal to generate flip-flop signals; and
a plurality of logic gates coupled to the pulse width modulation circuit and the flip-flops, and arranged to receive the pulse
width modulation signal and the flip-flop signals to generate the phased signals;
a plurality of transformers each having a secondary winding respectively coupled to a lamp; and
a plurality of bridge circuits each having a plurality of switches and being controlled by corresponding one of the phased
signals to conduct a current alternately flowing to and from a primary winding of corresponding one of the transformers.
|