L4984D Current-Mode PFC Controller
STMicroelectronics L4984D Current-Mode PFC Controller operates 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 a few hundred W to 1KW and above. The highly linear multiplier includes a special circuit that is able to reduce the crossover distortion of the AC input current and allows wide-range maintenance operation with a reasonably low THD, even over a large load range.
