Research Of White LED Based On AC Chip Integrated Fabrication

The alternating current(AC)light emitting diode(LED)has longer lifetime than direct current(DC)LED,because it can alternately turn on two sets of LED grains in an alternating cycle.However,for white AC LED,there are still the following problems.Firstly,the optical coherence and color region stability are poor.Secondly,the luminous efficiency of AC LED is low and the power is also not high,which can not meet the requirements of large-scale commercial lighting.Finally,the AC is used to drive the AC LED,and the isolation between load and power is difficult,so there is still risk in security.This paper is based on AC chip structure,semiconductor light-emitting principle and phosphor precipitation theory by adopting integrated packaging to solve the circuit security risk.The stability and luminous efficiency of white LED are improved by controlling the precipitation of phosphor.It was mainly carried out the following issues.(1)The phenomenon of phosphor precipitation of white LED with 3.5 W,220 V and 3000 K was integrated during packaging,and 7 sets of control experiments were set up to examine the phenomenon of optical coherence and colour region coordinate instability.(2)The results show when phosphor sedimentation time is between 0 and 20 min,the colour coordinate placement is concentrated,and the central coordinates are(x = 0.4432 ± 0.004,y = 0.4052 ± 0.002),with Supply/Demand Chain Management(SDCM)no greater than 7.When phosphor sedimentation time is between 30 and 40 min,the central coordinates are(x = 0.4366 ± 0.003,y = 0.4012 ± 0.003),with SDCM value high than 7,more discrete colour placement and large volatility,which is not accord with international standard for general lighting LED module performance requirements.(3)Based on white LED packaging,the FLoEFD software is used to simulate the heat distribution of white LED lamps.Through the analysis,it is found that the working temperature of the LED device accords with the laboratory test standard and meets the requirements of industrial production.