ST L4984D 基于L4984D连续导通模式PFC预稳压器参考设计方案

ST公司的L4984D是一款线性调制确定关断时间控制电流型PFC控制器，在该控制器工作在连续导通模式时，作为升压PFC转换器具有线性调制确定关断时间控制属性允许工作在确定频率操作模式。该芯片采用10引脚的SO封装，在连续导通模式下，工作在升压PFC预稳压状态时兼容EN61000-3-2 和JEIDA-MITI标准。该芯片可提供功率跨度从几百瓦到一千瓦及以上。本文首先介绍芯片的简介、特性、内部框图及应用领域，并给出相应设计方案的设计原理图、元器件列表及PCB元件布局图。

The L4984D is a current-mode PFC controller operating with line-modulated fixed-off-time (LM-FOT) control. A proprietary LM-FOT modulator allows fixed-frequency operation for boost PFC converters as long as they are operated in CCM (continuous conduction mode).

The chip comes in a 10-pin SO package and offers a low-cost solution for CCM-operated boost PFC pre-regulators in EN61000-3-2 and JEIDA-MITI compliant applications, in a power range that spans from few hundred W to 1 KW and above.

The highly linear multiplier includes a special circuit, able to reduce the crossover distortion of the AC input current, that allows wide-range-mains operation with a reasonably low THD,even over a large load range.
..

查看全文