Design of a Snubber Circuit for Switching Power Supply

Three snubber circuits to prevent switching power supply from over-voltage are investigated.Their advantages and design considerations are analyzed and compared.For RCD snubber circuit,the clamp voltage can be reduced by reducing its resistor value,which,however,leads to higher power losses.For LCD snubber circuit,the resonant frequency is supposed to be lower than the switching frequency.The energy regenerative snubber circuit has relatively lower clamp voltage,requiring no extra inductor.Finally,design of LCD snubber circuit is presented,which achieves lossless clamping.