COMMON-MODE FILTER HAVING HIGH CUT-OFF FREQUENCY

摘要

PURPOSE: A common-mode filter is provided to improve a high-voltage endurance characteristic and a reliability of the filter by raising a cut-off frequency. CONSTITUTION: A common-mode filter includes a magnetic or non-magnetic drum type core(10) having a core portion and a pair of integrated flange portions(12) disposed on opposite sides of the core portion, an electrode(20) arranged on the flange portions of the drum type core, and at least two wires(1,2) wound on the core portion of the drum type core and having terminals connected to the electrode. Each of the flange portions of the drum type core has a groove between corresponding two of the electrodes, and a protrusion(16) for separating the groove to two parts. The wires are wound on the core portion of the drum type core in a distributed winding manner thereby providing an inter-wire distance(a) between the wires and a winding pitch(b) between adjacent turns of each of the wires. The wires are drawn out through the grooves one by one while separated by the protrusions so that the ends of the wires are connected to the electrodes.