BM1051F is compounded LSI of Power Factor Correction converter (PFC) for harmonic solution and DC/DC converter (DC/DC). Because DC/DC operates on Quasi-resonant method, DC/DC contributes to Low EMI. BM1051F built in a HV starter circuit that tolerates 650V. Because of putting the current sense resistors externally both the PFC part and the DC/DC part, IC enables power supply design free. In the PFC part, IC adopts peak current control operation. Suitable application is proposed by a various protection circuit, such as the multiplier with a revision circuit on the AC voltage falls, the load regulation revision circuit, and the maximum power feed-forward circuit, etc. The Quasi-resonant system of a DC/DC part contributes to low EMI because PFC operates by soft switching. A burst mode is built in, so the power is reduced at light load. Various protection functions, such as a soft start function, a burst function, an over-current limiting for every cycle, overvoltage protection, and over current protection, are built in. The pin for communicated control with a controller and the external stop pin are prepared; it proposes the system that can be adapted for various applications.You can choose from a variety of power and topologyevaluation boards.