The MP44011 is a boundary-conduction–mode PFC controller with an internal-harmonic–injection function. It provides simple and high-performance active power-factor correction with minimal external components. Compared against traditional boundary-conduction–mode PFC controllers, the harmonic-injection function makes the part suitable for LED lighting applications. In LED lighting applications with two-stage structures, the harmonic-injection function can effectively reduce bus capacitance between the AC/DC and the DC/DC stage. In addition, harmonic injection can reduce the transformer size to save board space and BOM cost. Also, the benefits of a harmonic-injection function also apply to general boost or flyback PFC applications. The MP44011 is derived from the MP44010, except with a harmonic-injection function. The MP44011 is available in an 8-pin SOIC package.