TEA1721BT

TEA1721BT HV start-up flyback controller with integrated MOSFET for 5 W applications, 905 Hz burst frequency Rev. 2.1 — 7 June 2012 Product data sheet 1. Product profile 1.1 General description The TEA1721 is a small and low cost module Switched Mode Power Supply (SMPS) controller IC for low power applications (up to 5 W) and operates directly from the rectified universal mains input. The device includes a high voltage power switch (700 V) and 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 start-up directly from the rectified mains voltage without any external bleeder circuits. The converter operates as a regulated voltage source from no-load up to the maximum output current and operates as current source that delivers the maximum current over a broad output voltage range. Using the TEA1721, a low power converter can be built at minimum cost and with the minimum number of external components. The controller regulates the output voltage with primary-side sensing which eliminates the need for an additional secondary feedback circuitry and simplifies the design. At higher power levels, a frequency and current control mode is used. It operates with burst mode control at low power levels and no-load condition. The burst mode minimizes audible noise and provides an energy saver state which reduces the power consumption in no-load condition...