Analysis and Implementation of AC LED Driving Circuits

• Main Authors: Chung-yue Chen, 陳長嶽
• Other Authors: Ｙie-Tone Chen
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/18914313242656714133

碩士 === 雲林科技大學 === 電機工程系碩士班 === 98 === This thesis presents an AC LED electrical control circuit with light stabilization function. The output luminance of the AC LED will be variable while the input voltage is changed. In addition, if the input voltage rises too high, it will cause the AC LED being overheated and reduce the efficiency. Although the traditional structure of the AC LED with external resistance can simply control the output luminance of the AC LED, it is unable to keep the output luminance in the stable state while the input voltage is changed. Therefore, a light adjustment and temperature-controlled circuit for AC LED is presented in this thesis first, to control the light and temperature of the AC LED at different input voltage condition. However, this circuit is still unable to keep the variation of the output luminance less than 20%. So a new control circuit for AC LED with light stabilization function is further proposed. By using the voltage sensor circuit, the output luminance of the proposed AC LED driver can be adjusted automatically with adaption to the input voltage variation. The experimental results verify that the proposed light stabilization circuit of AC LED can automatically adjust the output luminance of the AC LED, and the variation of the output luminance is controlled to be lower than 20%. So the stability of the output luminance and the lifetime of the AC LED can be much improved.