| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a dimming circuit for controlling the luminance of a light source and a method for controlling luminance. <P>SOLUTION: The dimming circuit 400 includes an inverter circuit 430 and a driving circuit 420. The inverter circuit 430 is electrically coupled to a light source 440 to be controlled, to convert a direct current (DC) power input into an alternating current (AC) power. The inverter circuit 430 includes a transformer 434, a capacitor C1 connected in parallel to the transformer 434, a plurality of switches S1 and S2 located at both ends of the capacitor C1, and an oscillating circuit 432 electrically connected to both ends of the transformer 434. The driving circuit 420 is electrically connected to the inverter circuit 430, for controlling the time period that the light source 440 is turned on. As the input of DC voltage into the transformer 434 is stopped, the driving circuit 420 opens the plurality of switches S1 and S2 in the inverter circuit 430, forming electrical isolation between the capacitor C1 and the transformer 434, which prevents voltage oscillation and stores the energy into the capacitor C1. <P>COPYRIGHT: (C)2010,JPO&INPIT |
