Research On The Cold Cathode Flat Fluorescent Indicator Light

CCFL is a new kind of economic lamp-house on energy. this light has some excellence on long life time, high brightness, effective luminescence for long time, shockproof, normally startup in the circumstance of low temperature continually, and high lighting efficiency and economy on energy. By changing the driving shape, the lighting area is changed from tube shape to flat panel shape, so the commerce of the cold cathode fluorescent light is put into practice. But because the specially top-grade IC is used with costly value, especially the SCM is used for driving source, which results in the fatal limitation.This paper introduces the radial structure of the CCFL including the panel, driving IC, the outline, etc. and also this paper interprets its working principle in details. A new simple circuit is renovated by designing over again, the detailed case is as such, using the usual DM74LS123N IC as the controlling chip, connecting theoutput pin- Q₁ with the input pin- A₁ ,using the resistance- R₂ and the capacitance- C₃ as time-lapse unit, and so a multi-concussion circuit comes into being. And connecting the other output-pin Q₁|— and the other simple-stable trigger A₂. Q₂ isused to drive the N-MOS transistor of IRFZ48N sealed by TO-220, this leakage pole of the transistor controls the primary coil's connection and disconnection of the specially designed E16 high frequency transformer. A small shape three port manostat of 78L05 with the output current of 150mA is added on the electrical source end, so the input voltage is decreased from 15V to 12V to supply DM74LS123N.The above-mentioned circuit is welt with the glass panel which was made beforehand, and then we measure the electric performance of the CCFL, by contrast the quality of this light to the quality of the original one, these conclusions are drawn,(1) as a whole, the lighting uniformity is 87.9%, which is above 85% and up to the industry regulation;(2)the luminance of the CCFL is increased by 8.8% which isup to 7250 cd/m² ;(3)the average startup voltage is decreased from 390V to 337VThis new light has this performance which is proved by testing: the capability is...