Reduce and leaded to explosion risk's filter circuit because electric capacity becomes invalid

The utility model discloses a reduce and leaded to explosion risk's filter circuit because electric capacity becomes invalid, this filter circuit includes electric capacity C1, electric capacity C3, inductance L1, wherein, the positive and negative output at rectifier bridge BD1 is connected at electric capacity C1's both ends, rectifier bridge BD1's forward transportation output is connected to inductance L1 one end, the drain electrode of MOS switch tube is connected to the inductance L1 other end through transformer T1's primary, the drain electrode of MOS switch tube connects rectifier bridge BD1's negative output end, electric capacity C3 connects between the inductance L1 other end and rectifier bridge BD1's negative output end, this filter circuit still includes electric capacity C4, electric capacity C4 and electric capacity C3 are parallelly connected. The utility model discloses a parallel connection's electric capacity C3, C4 replace the main electric capacity of supplying power to make the main el