| 摘要 |
PROBLEM TO BE SOLVED: To provide a thin film common mode filter of simple structure which can be miniaturized for precise control while enhancing the common mode impedance.SOLUTION: A thin film common mode filter comprises: an insulating substrate of nonmagnetic material; and a coil main volume layer structure provided in the insulating substrate of nonmagnetic material. The coil main volume layer structure includes a first coil, a second coil, a third coil and a fourth coil. The first coil and third coil are electrically connected in series, and the second coil and fourth coil are electrically connected in series. Total wire length L (mm) and wire width W (mm) of the first, second, third and fourth coils satisfy the following relationship; ((7.2-fc)/3.0)<L/W<((8.15-fc)/2.7)]. In the formula, fc is the cut frequency of a differential mode signal. |
