Flyback Converter in Discontinuous Conduction Mode

Owing to its simplicity in topological structure, the flyback switching converter has enjoyed dominance in the low-power, less than 200 W, power supply market. For example, in personal computers, switching converters in flyback configuration certainly hold an undisputable edge over other topologies. Beside being simpler in design, flyback operation also offers one distinctive advantage, which is the inherent output short circuit protection. This natural benefit stems from the fact that, for this topology only, the energy transferring action takes place during the flyback phase when the main switch is nonconducting. Therefore, the switch is isolated from the short induced peak surge and the maximum power available is limited to the extent that a pulse-width modulator can stretch.