| 摘要 |
PROBLEM TO BE SOLVED: To provide a laminated balun transformer which can be further miniaturized while improving insertion loss characteristics in a pass band. SOLUTION: The balun transformer in which first and third strip lines are coupled with a coupler, second and fourth strip lines are coupled with a coupler and first and second balanced signals having mutually reverse phase are drawn out from the third and fourth strip lines is embodied by a laminate type. In this case, a conductive non-ground electrode is formed at the intermediate position of the third and fourth strip lines; the non-ground electrode by electromagnetic coupling of the third and fourth strip lines forms a ground; insertion loss in an operation band is improved; and an impedance and electromagnetic shield are embodied by utilizing the ground pattern of a mount surface without separately forming an internal ground electrode on the bottom layer in ground electrodes positioned on the top and bottom of the first-fourth strip lines, and embodying the electromagnetic shield from the outside, and the thickness of the element is reduced without deteriorating characteristics. COPYRIGHT: (C)2006,JPO&NCIPI
|
