Constant current electronic load with soft start function used for aging testing of LED power supply
Guo Zhuang-long · Modern Electronics Technique · 2013
The constant current electronic load with soft start function is design for LED power supply in this paper.It is used to control the classic simulation constant current load circuit through the constant voltage output circuit by the input voltage of the load terminals V+ and V-.In combination with the power-on delay start circuit composed of the simple RC delay network,it can make the load current rise slowly from 0mA to the rated current.With the power-down fast discharge circuit composed of dual transistors,resistors and capacitors,it can ensure the startup delay effect.The constant current electronic load with soft start function,which dose not need any external power supply,connects directly with the electronic load access voltage to realize pas sive soft start without software delay and other hardware delay.Its advantages are low cost,series and parallel application.In the LED power supply aging test,the soft start constant current electronic load can simulate the LED load instead of the resistance load in order to ensure normal LED power supply testing.