dc.description.abstract | This paper elaborates how to design a Pulse Mode Driver Circuit for Light Emitting Diode with Automatic Photo-Power Control, which can still maintain the stability of optical power in the circumstances of ambient temperature changes. Compare to other modes; the most important advantage of this paper is that it doesn’t need PhotoDiode from externals to induct the changes of LED optical power, while it can straightly make use from circuit to compensate the changes of LED optical power,. And compare to general successive driving modes, the driving mode based on Pulse Mode makes the applications of last stage lots more handier. According to the LED driven by Pulse Mode, driver current of red, green, and blue LED can respectively reach stable numbers 62.5mA, 37.5mA, and 37.5mA. The frequency of Pulse Mode circuit can reach, the highest number, 200Hz, but without the problems of phase delay. When the circuit is controlled by the Automatic Power Control without of PhotoDiode, it can maintain the stability of optical power in the temperature range of 0℃ to 70℃. And the stable optical power of red, green , and blue PhotoDiode are respectively 8.4mW, 5.2mW, and 9.9mW。About related applications; after practicing the pulse to drive RGB, when the number of Duty Cycle is 1:3:1, the highest CRI number 78.789 will be reached. And upon the Duty Cycle number are respectively 2:3:1, the closest color temperature to 6500K, 6534K can be acquired, meanwhile, the CRI number will be 52.299.
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