Summary: | 碩士 === 逢甲大學 === 自動控制工程學系 === 103 === As the epitaxial process for the manufacture of light emitting diodes (LED) and packaging technology has been continuously improved, the lifetime and luminous efficiency of LEDs have increased greatly. Due to the thermal energy affects on the electrical property of LED, its driving power requires constant current control to adjust brightness. However, this approach needs extensive electronic parts to conduct signal processing, which will decrease the reliability and lifetime of LED. Moreover, as the packaging volume increases, manufacturing costs become relatively higher. In order to address these problems, a silicon-based LED packaging module with a temperature compensating capacitor is proposed, which can provide stable luminous efficiency, and be applied to the constant voltage driving mode. The packaging module uses 3D stacking technology to integrate LED and capacitor on a silicon micromachining substrate. The inductor is used for electrical impedance with capacitor, when supplying a constant voltage with periodical switch mode to LED. Based on this configuration, the temperature variation that generated by the LED can directly changes the capacitance in a series driving circuit; thereby, compensating the resistance variation in the LED to stable the driving current. Thus, a miniaturized, low-cost, constant voltage controllable LED lighting module can be achieved.
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