| Light Emitting Diode is a kind of semiconductor lamp-house invented in the late 1960s. In the recent years, LED's manufacture technology has developed a lot and its luminous intensity has improved evidently, which makes it possible to be used in illumination. Further more, LED has its advantages of smallness, long life, quick response, etc. So the research of LED replacing traditional lamp-houses is practical and significant.With a view to the application of LED in traffic field, this paper designed the LED traffic lamp and the LED flash lamp of new type; research the problem of LED's brightness adjustment and high-power LED driving technic. Thus advantages of LED compared with traditional lamps are developed in the traffic field. A traffic control system is designed to realize the linkage control of signal lamp and flash lamp, complex with the function of brightness dimming at night and time data setting. Thus signal lamp causing giddiness at night is avoided, and leading traffic is more capable.Standard LED and 1W high-power white LED are chosen as the lamp-house based on the present state of LED productions. Different driving circuits are designed aiming at the difference of LED's characteristics, emphasized respectively on Pulse-Width Modulation dimming and constant current driving. MSP430F149 as the core, traffic control system is realized, which outputs the control signal to traffic lamp and flash lamp and realizes the linkage control function. PWM dimming pulse is output making use of real time clock module to change brightness according to the alternation of day and night. By 485 interface and key board, time data is inquired and changed to realize the function of time data setting. The software system is programmed in C language.With the improvement of LED products' capability and technology, LED traffic signal lamp, high-power LED flash lamp of electronic police and the control system will surely take the place of traditional lamps and improve their characteristics.
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