原标题：Allegro A6262汽车LED阵列驱动方案

　　Allegro公司的A6262是汽车LED阵列驱动器，是线性可编程电流稳压器，四个输出中每一个能提供高达100mA的电流，每个输出电流精度达5%，每串电流匹配优于10%，6-50V工作电源，可驱动高亮LED(HB LED)阵列,工作温度–40℃到150℃，主要用在屋顶照明，地图照明，空间照明以及情景照明等。本文介绍了A6262主要特性和优势，功能方框图以及采用各种电源和输出的典型应用框图。

　　A6262: Automotive LED Array Driver

　　The A6262 is a linear, programmable current regulator providing up to 100 mA from each of four outputs to drive arrays of high brightness LEDs. The regulated LED current from each output, accurate to 5%, is set by a single reference resistor. Current matching in each string is better than 10% without the use of ballast resistors. Driving LEDs with constant current ensures safe operation with maximum possible light output. Output control is provided by an enable input, giving direct control for PWM applications, and by a debounced switch input, proving an on/off toggle action.

　　For automotive applications, optimum performance is achieved when driving 4 strings with 1 to 3 LEDs in each string, at a total current of up to 100 mA in each string. Outputs can be

　　connected in parallel or left unused as required.

　　Short detection is provided to protect the LEDs and the A6262 during a short-to-ground at any LED output pin. The output will automatically resume the regulated current when the short is removed.

　　A temperature monitor is included to reduce the LED drive current if the chip temperature exceeds an adjustable thermal threshold.

　　The device packages are a 10-pin MSOP (LY) and a 16-pin TSSOP (LP), both with exposed pad for enhanced thermal dissipation. They are lead (Pb) free, with 100% matte tin leadframe plating.

　　A6262主要特性和优势：

　　▪ Total LED drive current up to 400 mA

　　▪ Current shared equally up to 100 mA by up to 4 strings

　　▪ 6 to 50 V supply

　　▪ Low dropout voltage

　　▪ LED output short-to-ground and thermal protection

　　▪ On/off toggle switch input

　　▪ Enable input for PWM control

　　▪ Current slew rate limit during PWM

　　▪ Current set by reference resistor

　　▪ Automotive K-temperature range version (–40℃ to 150℃)

　　A6262应用：

　　▪ Dome light, map light, space lighting, mood lighting

　　图1。A6262功能方框图

　　图2。A6262典型应用框图

　　图3。A6262各种电源和输出选择典型应用框图

　　图4。A6262采用SW和EN一起的典型应用框图