高調光比新型汽車日行燈HB LED光源驅動器

摘要：高亮度LED用于汽車大燈是未來的發展方向，其中HB LED日行燈已開始作為產品應用于一些高檔轎車。本文設計了一款基于專用IC MAX16831與反激式變換器的汽車日行燈HB LED驅動電路，實現了HB LED的恒流驅動和PWM調光，并能滿足日行燈的有關驅動要求。詳細介紹了線路的設計原理，并對PWM調光控制功能和調光比影響因素等進行了分析，給出主要實驗參數和實驗結果，輸入電壓6V～19V，輸出電壓40V～57V，PWM調光占空比可調5％－100％，輸出LED電流160mA，有關實驗驗證了所給出設計的可行性。 敘詞：高亮度LED MAX16831 恒流 PWM調光 調光比 Abstract：Applying high brightness LED to car lamps is future trend of this industry, and even now HB LED daytime running lamps(DRLs) have been installed in some high-end cars. This article designs an automobile DRL HB LED driving circuit based on the use of IC MAX16831 and flyback convertor, which realizes constant-current drive and PWM dimming and in the meantime can meet related driving requirements of DRLs. The author introduces in detail the principles of designing the circuit, analyzes some factors such as the function of PWM dimming control and the influence of dimming ratio, and finally, presents major experimental parameters and results as follows: input voltage 6V to 19V, output voltage 40V to 57V, PWM dimming adjustable duty cycle 5% to 100%, and LED output current 160mA. Related experiments demonstrates that the design is applicable. Keyword：High Brightness LED, MAX16831, Constant Current, PWM Dimming, Dimming Ratio