The fly-back converter is used in both AC/DC and DC/DC conversion with galvanic isolation between the input and outputs. More precisely, the fly-back converter is a buck boost converter with the inductor split to form a transformer, so that the voltage ratios are multiplied with an additional advantage of isolation. In the on-state the energy is transferred from the input voltage source to the transformer while the output capacitor supplies energy to the output load. In the off-state, the energy is transferred from the transformer to the output load and the output capacitor. By controlling the duty ratio of switch used in the primary of transformer a DC supply of zero to a desired maximum value is obtained. A fly-back transformer is designed to meet the output requirement. In this project the aim is to design a pure DC supply that can be used to obtain the output of 48V.

Flyback converter , IC UC3843, MOSFET,Transformer core

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