The 2577T is a step-up regulator device finding many applications in flyback & forward convertor switching regulation. A typical arrangement requires only a few external components to realise a working design. Using existing value inductors & flyback transformers simplifies circuit design. Output currents up to 3A are possible with this device from a wide range of input voltages 3.5V to 40V. Output voltages up to 60V can be developed depending on the output current required. Step-up is achieved using the internal 52k Hz fixed frequency oscillator & developing a voltage across an inductor or transformer. The current from the device charges the output capacitor & feedback maintains it at a constant voltage. A load can then be connected to the output which is regulated to the desired voltage. Other features of the device are a soft start mode internal protection against overcurrent limit thermal limiting & undervoltage lock-out. Applications include simple boost regulators flyback & forward regulators & multiple output regulators.