The Study Of AC Driving Power LED Unit Electrothermal Characteristics

LED, as its luminescent efficiency increasing by years, has been the researching focus, of which the application fields is broaden. Conventional illumination has more advantages than semiconductor which is centering with high-power LED. The electroheat characteristics of high power LED is studied in this article, and the main occupation can be summarized as:(1) we analysed the structures of the high-power LED chip of series of GaN substrate according to the ones produced by Pengyuan photoelectricity company, and the electrical features effect by the different active layers, thickness, the substrate, P-GaN, N-GaN, cementation meterials, pedestal, hatching is researched. In addition, the influence to the electrical features of different structures of LED, like the forward-form or backward, are well investigated, respectively.(2) The electrical model of LED in the case of alternating current(AC) weak signal is established. LED is researched as an special P-N junction, and its electrical features, such as the leakage current, junction capacitance, rectification effect, are well studied. We also obtain the variation of these parameters under the alternating current excitation. The periphery AC driver module is designed, and the simulation is well complished based on the proposed system. Therefore, a stable LED system driven by pulse AC at low voltage, in which overcurrent and over temp protection are embedded. At last, the circuit simulation of the system is enforced.(3) The heat-removal system is proposed, which is encapsulation independent. Meanwhile, the sysetem can afford LED lighting driven by AC. The heatsource and heatremoval layers of the system are analysed detailed, furthermore, the entire thermal resistance can be calculated by the chip breakdown principle so that the reliability of the designed heatremoval system is well proved, since the active refrigeration is emploied. Therefore, the heatremoval is obviously.