Research And Design Of High Power LED Temperature Control System Based On Cortex-M3

Compared with the traditional light source,the new fourth generation LED has the advantages of high luminous efficiency,long service life,high safety and high reliability.And the LED drive control device has updated continuously because of the drastic development of the LED.In this paper,a load identification system based on Cortex-M3 technology is designed for high-power LED design,and the corresponding control drive is adopted to achieve the temperature control.Currently,the development of LED technology target mainly includes three aspects: the stability of light efficiency,energy saving and light source chip,this paper developed a high-power LED temperature control scheme to help the high power LED work under the given parameters and different environment,and ensure its stable current.The constant current driving mode is the most commonly used to drive the high-power LED,which could guarantee the stability of the LED luminous efficiency.However,the starting current of different structured light source chips has the difference,it is necessary to replace the driving power.Hence,it is vital to design a new LED light source driving device which could realize the conversion of constant current and constant power when the environment changes.The high power LED is easily affected by the environment and heat dissipation when used in practice.In order to make the driving device adapt to the different environment,the designed system should be able to monitor the changes of the working conditions and the temperature of the high power LED,when these two factors are monitored well,the efficiency of the control of the LED temperature and the luminescence would be largely improved.At the same time,it is necessary to judge the faults of the system and solve the problems in time.It can not be a vicious circle,resulting in a complete paralysis of the system.In view of the above content,the temperature control system in this paper chooses Cortex-M3 as the core,uses the variable frequency power sources to provide the stable voltage,Simultaneous use the A/D module to collect the LED current voltage signal.The temperature sensor is used to monitor the temperature signal of the LED,and environmental illumination can be monitored by photosensitive sensor which could collect the environmental illumination signal when LED working.Finally,considering the environment and its own load,and controlling the LED temperature reasonably can make LED keep high luminous efficiency.