原标题：Maxim MAX25611汽车高压HB－LED控制器解决方案

　　Maxim公司的MAX25611A/MAX25611B是单路HBLED驱动器,主要用在汽车前端照明如远光,近光,日间行车灯(DRL),转向指示灯,雾灯和其它LED照明.输入电压5V-36V,最大输出电压65V,可以驱动一串LED灯.PWM输入提供LED调光比高达5000:1,而REFI输入提供另外模拟调光功能.器件采用广谱调制,以改善电磁兼容性能.MAX25611A/MAX25611B还可以用在Zeta和Cuk转换器配置.满足汽车规范AEC-Q100,可以组成升压,降压-升压,高边降压,Zeta和Cuk转换器等拓扑.主要用在汽车外部照明,远光/近光/信号/位置灯,日间行车灯(DRL),雾灯和自适应前灯总成,抬头显示器以及商用,工业和建筑物照明.本文介绍了MAX25611主要优势和特性,功能框图,多种应用电路包括升压应用,降压-升压应用,高边降压应用,SEPIC应用,Zeta应用,直流开关电源(CUK变换器)应用和电压稳压器应用电路图等以及评估板MAX25611 EVK主要特性,电路图,材料清单和PCB设计图.

　　The MAX25611A/MAX25611B are single-channel HBLED drivers for automotive front light applications such as high beam, low beam, daytime running light (DRL), turn indicator, fog light, and other LED lights. It can take an input voltage from 5V to 36V and can drive a string of LEDs with a maximum output voltage of 65V.

　　The MAX25611A/MAX25611B sense output current at the high side of the LED string. High-side current sensing is required to protect for shorts from the output to the ground or battery input. It is also the most flex­ible scheme for driving LEDs, allowing boost, high-side buck, SEPIC mode, or buck-boost mode configurations. The PWM input provides LED dimming ratios of up to 5000:1, and the REFI input provides additional analog dimming capability in the MAX25611A/MAX25611B. The MAX25611A/MAX25611B have built in spread-spectrum modulation for improved electromagnetic compatibility performance. The MAX25611A/MAX25611B can also be used in zeta and Cuk converter configurations if it is necessary in some applications.

　　The MAX25611A/MAX25611B are available in a space-saving 12-pin SWTQFN-EP package. They are speci­fied to operate over the -40°C to +125°C automotive temperature range. The switching frequency is internally set at 350kHz for the MAX25611A and 2.2MHz for the MAX25611B.

　　MAX25611主要优势和特性:

　　Automotive Ready: AEC-Q100 Qualified

　　Integration Minimizes BOM for High-Brightness LED DriverIntegrated pMOS Dimming FET Gate Driver Allows Single-Wire Connection to LED String

　　PWM, Analog-to-PWM and Analog Dimming

　　Integrated High-Side, Current-Sense Amplifier

　　12-Pin SWTQFN-EP Package

　　Flexible Application Configurations+5V to +36V Wide Input Voltage Range with a Maximum +65V Boost Output

　　Boost, Buck-Boost, High-Side Buck, SEPIC, Zeta, and Cuk Single-Channel LED Drivers

　　Protection Features and Wide Temperature Range Increase System Reliability Short-Circuit, Overvoltage, and Thermal Protection

　　-40℃ to +125℃ Operating Temperature Range

　　MAX25611应用:

　　Automotive Exterior Lighting

　　High Beam/Low Beam/Signal/Position lights

　　Daytime Running Lights (DRLs)

　　Fog Lights and Adaptive Front Light Assemblies

　　Head-Up Displays

　　Commercial, Industrial, and Architectural Lighting

　　图1.MAX25611功能框图

　　图2.MAX25611简化应用电路图

　　图3.MAX25611典型应用电路图

　　图4.MAX25611典型升压应用电路图

　　图5.MAX25611典型降压-升压应用电路图

　　图6.MAX25611典型高边降压应用电路图

　　图7.MAX25611典型SEPIC应用电路图

　　图8.MAX25611典型Zeta应用电路图

　　图9. MAX25611典型直流开关电源(CUK变换器)应用电路图

　　图10.MAX25611电压稳压器应用电路图

　　评估板MAX25611 EVK

　　The MAX25611 evaluation kit (EV kit) provides a proven design to evaluate the MAX25611A/MAX25611B auto­motive high-voltage, high-brightness LED (HB LED) controller. The EV kit is set up for boost and buck-boost configurations and operates from a 6V to 18V DC supply voltage. The EV kit is configured to deliver up to 0.88A to one string of LEDs. The total voltage of the string can vary from 3V to 36V. The anode of the LED string should be connected to the LED+ terminal. The cathode of the LED string can be connected either to GND (boost mode) or IN (buck-boost mode). In the case of boost mode, the input voltage should not exceed the LED string voltage.

　　评估板MAX25611 EVK主要特性和优势:

　　Configured for Boost and Buck-Boost Application

　　Analog Dimming Control

　　Proven PCB Layout

　　Fully Assembled and Tested Feature

　　图11.评估板MAX25611 EVK电路图

　　评估板MAX25611 EVK材料清单: