应用与设计

LT1249 具有源功率因数校正功能的 90VAC 至 270VAC 通用离线电源系统

详情介绍

概览

产品详情

Active Power Factor Correction for 90VAC to 270VAC Universal Offline Power Systems

LT1249 采用一个包含了由电压放大器提供的一种平方增益功能的乘法器,以降低轻输出负载时的 AC 增益,从而保持低线路电流失真和高系统可靠性。另外,LT1249 还提供了滤波功能,旨在降低当馈入乘法器时有可能引发不稳定性的线路开关噪声。通过在乘法器的电流输入端上设置低偏置电压,最大限度地缩小了线路电流死区。


LT1249 拥有包括峰值电流限制和过压保护在内的诸多保护功能。开关频率在内部设定为 100kHz。


LT1249 凭借极少的元件数目简化了 PFC 设计,而 LT1248 则在开关频率、过压和电流限制方面提供了灵活性。


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