应用与设计

具热降额功能的 30W 白光 LED 车前灯驱动器

详情介绍

概览

产品详情

TRIAC Dimmable 20W Offline LED Driver Using the LT3799

本电路示出了一款完整的 LED 驱动器解决方案。LT3799 从主端开关电流波形来检测输出电流。该 IC 利用一种新颖的反馈控制来调整峰值开关电流和占空比,由此调节输出电流。与其他需要了解输入功率和输出电压信息的主端检测方法不同,此种新型方案可提供大为改善的输出电流调节性能,这是因为准确度仅仅受到变压器绕组电阻、开关接通电阻 R DS(ON)、输出二极管正向电压降和 LED 电缆电压降的影响。

工具及仿真模型

LTspice

LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

To launch ready-to-run LTspice demonstration circuits for this part:

Step 1: Download and install LTspice on your computer.

Step 2: Click on the link in the section below to download a demonstration circuit.

Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.

LTspice