Study of Alternating electricity voltage for High Power AC LED

• Main Authors: MING-TE LIN, 林明德
• Other Authors: 孫慶成
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/06117705555394417841

碩士 === 國立中央大學 === 光電科學研究所碩士在職專班 === 95 === In this thesis, we study so-called AC-LEDs, which can be driven by AC electrical power directly. We build up an equivalent circuit to model the electrical characteristic of the AC-LED. We apply "ITRI''s limited LED package" on AC-LEDs to study the effect by driving the LEDs with the general electrical power system. In room temperature, we obtain that the output brightness holds at the same level or above when the 20%-30% chips fail since the critical voltage drops but the drive current and power increase. Such characteristic enables AC-LED suitable to security-required lighting systems because the variation of the drive current and power can be applied to failure estimation so that the damage LEDs can be replaced before the lighting brightness drops.