UCC28056 High Performance PFC Controllers Texas Instruments UCC28056 6-Pin High-Performance PFC Controllers offer an innovative mixed-mode method derived from the devices’ PFC boost stages. The mixed-mode method operates in Transition Mode (TM) at full load and transitions smoothly into Discontinuous Conduction Mode (DCM) at a reduced load, resulting in an automatically decreasing switching frequency. The device includes burst mode operation eliminating the need to switch off the PFC, improving light load performance, and allowing systems to meet demanding energy standards. The Texas Instruments UCC28056 ensures sinusoidal line input current with low distortion while the PFC stays on via the PFC power stage, driving power to 300W. Combined with the UCC256301 LLC controller, the need for an auxiliary flyback converter is eliminated. The UCC28056 provides an instant turn-on feature and minimizes the external component count.