NS LM3433 带高频调光HBLED驱动方案
NS 公司的LM3433是带高频调光的HBLED驱动器,为大功率LED提供了恒流照明.工作输入电压为-9V到-14V,输出电流大于6A,PWM频率大于30kHz,适用于共阳极LED,不需要输出电容,开关频率高达1MHz,静态电流典型值为1mA,具有软起动特性,可用于LCD背景光,投映系统,固态照明和汽车照明.本文介绍了LM3433主要特性,方框图, 典型应用电路以及输出电流2A – 6A 和2A - 14A应用电路和评估板电路图与材料清单.
LM3433: Common Anode Capable High Brightness LED Driver with High Frequency Dimming
The LM3433 is an adaptive constant on-time DC/DC buck (step-down) constant current controller (a true current source). The LM3433 provides a constant current for illuminating
high power LEDs. The output configuration allows the anodes of multiple LEDs to be tied directly to the ground referenced chassis for maximum heat sink efficacy. The high
frequency capable architecture allows the use of small external passive components and no output capacitor while maintaining low LED ripple current. Two control inputs are used to modulate LED brightness. An analog current control input is provided so the LM3433 can be adjusted to compensate for LED manufacturing variations and/or color temperature correction...
