Sunday, July 18, 2010

Simple 20 Watt Switcher Forward Converter

This is design circuit for step-down regulator can be developed using the LM2577 Simple Switcher IC in a forward converter topology. This design allows the LM2577 IC to be used in step-down voltage applications at output power levels greater than the 1 A LM2575 and 3 A LM2576 buck regulators. This is the figure of the circuit.





Diodes, DR and DF, used in the secondary are 5A, 30V Schottky diodes. The same diode type is used for Dc, however a lower current diode could have been used. A compensation network of Rc and Cc optimizes the regulator’s stability and transient response and provides a soft-start function for a well-controlled power-up. [Circuit source: National Semiconductor Notes].