| 摘要 |
PURPOSE:To suppress the noise in electromagnetic induction or the switching noise to a commercial Ac power source line, caused by the high peak value of the switching current flowing through an AC-DC converter circuit. CONSTITUTION:In an AC-DC converter, where a rectifier 1 connected to a commercial power source, the primary winding n1 of a converter transformer T1, and the first switching transistor Q1 are connected in series, a DC-DC converter 7 is connected to the output side of the rectifier 1, and a detection circuit 9 and a control driving circuit 8 for synchronizing the first switching transistor Q1 and the second switching transistor Q2 are provided. Hereby, the current I3 flowing to the switching transistor Q1 of the AC-DC converter and the current I4 flowing to the DC-DC converter 7 do not flow at the same time, therefore the peak value of the switching current can be suppressed. |
