The TEA1720BT is a small and low cost Switched Mode Power Supply (SMPS)
controller IC for low power applications (up to 12.5 W) and operates directly from the
rectified universal mains input. The device includes an emitter switch for driving an
external low-cost bipolar power transistor. It has been optimized for flyback converter
topologies to provide high-efficiency over the entire load range with ultra-low power
consumption in the no-load condition. It provides a circuit for fast start-up directly from
the rectified mains voltage without any external bleeder circuits.