The MAX5974A is optimized to be used in inductively coupled flyback configurations. The MAX5974A features unique circuitry to achieve output regulation without using an optocoupler. Different from traditional direct output voltage feedback through opto-coupler circuits, the MAX5974A uses an auxiliary winding to sense the voltage at the secondary output winding . The power supply is regulated by sensing the induced auxiliary winding voltage V AUX . The auxiliary winding’s circuit filters this induced voltage and regulates the output voltage V OUT indirectly by regulating the scaled version of V AUX which is fed to the FB pin of the converter using a resistor divider network.