【LP3321】TSOT-23封装升压驱动器。单列驱动2~拾颗白光LED
LP3321概述
LP3321是一款专为白光LED设计的升压型恒流驱动器。LP3321通过LED串联使得每一个LED通过相同电流,从而获得均匀亮度。1MHz的工作频率允许用户选用较小的外部元器件。相比于其它应用方案,输出电容可以减小至0.22μF,节省了面积和成本。回馈电压低至0.3V,极大程度地减小了回馈电阻上的功耗。LP3321具有很高的输出电压,使其完全能够驱动串联的拾颗白光LED,为中、大型屏幕提供背光。可以通过三种方式调节LED亮度:DC电压调节、逻辑信号调节、PWM信号调节。芯片使能端可以保证芯片在关断时静态电流为零。
LP3321采用TSOT23-5封装。
LP3321特点
• 2.6V~5.5V输入电压
• 最高输出电压38V,具有过压保护功能
• 内置软启动功能
• 具有Analog/PWM两种亮度调节方式
• 内置40V高压功率管
• 工作频率高达1MHz
• 外围元件尺寸小
• TSOT23-5封装
• 符合RoHS规范及Pb-Free
LP3321应用
• GPS 导航系统
• 便携媒体播放器
• 手持设备、数码相机
• 便携游戏机
LP3321概述
The LP3321 is a 1.3MHz PWM boost switching regulator designed for constant- current white LED driver applications. The LP3321 can drive a string of up to 10 white LEDs in series, ensuring uniform brightness and eliminating several ballast resistors. The LP3321 implements a constant frequency 1.3MHz PWM control scheme. The high frequency PWM operation also saves board space by reducing external component sizes. To improve efficiency, the feedback voltage is set to 195 mV, which reduces the power dissipation in the current setting resistor. Highly integration and internal compensation network minimizes as 5 external component counts. Optimized operation frequency can meet the requirement of small LC filters value and low operation current with high efficiency.
LP3321主要特征
· High Efficiency: 90%
· 1.3MHzFixed-Frequency PWM Operation
· Maximum Output Voltage up to 40V
· Operating Range : 2.7V to 5.5V
· Shutdown Supply Current:<1uA
· Available in TSOT23-5/TSOT23-6 Package
· Built-in 40V Over Voltage Protection
· Minimize the External Component
· RoHS Compliant and 100% Lead (Pb)-Free
LP3321应用领域
· WLED Backlight driver
· OLED Backlight driver
· PDA
· MID/PTV