| 摘要 |
PROBLEM TO BE SOLVED: To provide a filter circuit capable of absorbing kickback voltage caused by surge noises entering from the exterior without increasing terminal noise. SOLUTION: A varistor 8 and bead inductors 9a, 9b are placed and connected in series in a line 15 connected in parallel before and behind a common mode coil 1. At this time the bead inductors 9a, 9b are positioned on both sides of the varistor 8. As a result, kickback voltage generated in the common mode coil 1 by noises entering from the exterior is clamped by the varistor 8; meanwhile, high-frequency noises generated from a DC-DC converter 6 is absorbed into the bead inductors 9a, 9b, the common mode coil 1 and capacitors 3a, 3b. |
