Beschreibung
This combination IC integrates power factor correction (PFC) and quasi−resonant flyback functionality necessary to implement a compact and highly efficient LED driver for high performance LED lighting applications.
The PFC stage utilizes a proprietary multiplier architecture to achieve low harmonic distortion and near−unity power factor while operating in a Critical Conduction Mode (CrM). The circuit incorporates all the features necessary for building a robust and compact PFC stage while minimizing the number of external components.
The quasi−resonant current−mode flyback stage features a proprietary valley−lockout circuitry, ensuring stable valley switching. This system works down to the 4th valley and toggles to a frequency foldback mode with a minimum frequency clamp beyond the 4th valley to eliminate audible noise. Skip mode operation allows excellent efficiency in light load conditions while consuming very low standby power consumption.