基于MAX16834设计的112W升压LED驱动器技术

     MAX16834 是电流模式高亮LED(HBLED)驱动器，可用于升压，升压-降压,SEPIC和高边降压拓扑。工作电压4.75V 到 28V，3000:1 PWM调光/模拟调光，可编频率从100kHz到1MHz，主要用在单串LED LCD背光,汽车前后照明，投映系统RGB LED光源，点和环境照明以及DC/DC升压/升-降压转换器。本文介绍了MAX16834主要特性，方框图，多种应用电路以及112W升压LED驱动器参考设计，电路图和材料清单(BOM)。

图1.MAX16834内部方框图

图2.MAX16834升压LED驱动器

图3.MAX16834升压-降压LED驱动器(VLED+ < 28V)

图4.MAX16834带汽车负载突变保护的升压LED驱动器

图5.MAX16834高边降压LED驱动器

图6.MAX16834升压DC/DC转换器

图7.MAX16834升压-降压DC/DC转换器

　　全陶瓷电容的112W升压长串LED驱动器参考设计

　　112W boost driver for long strings of LEDs using all ceramic capacitors

　　This is a reference design for a 112.5W boost LED driver that uses the MAX16834 for long strings of LEDs. These long LED strings are commonly found in streetlights and parking garage lights.

　　Input voltage: 24VDC ±5% (at 1.49A)

　　VLED configuration: Two parallel strings. Each string consists of 19 WLEDs and a 5Ω resistor for current balancing. Current is 750mA per sting for a total of 1.5A into 75V.

　　Dimming: 50μs (min) on-pulse for up to a 200:1 dimming ratio with a 100Hz dimming frequency

图8.112W升压长串LED驱动器参考设计外形图

图9.112W升压长串LED驱动器参考设计电路图

　　112W升压长串LED驱动器参考设计材料清单(BOM):