Patent ID: 8471645

Claim:
A balanced-unbalanced transformer comprising: a balanced transmission line including paired transmission lines for input or output of a balanced signal, the paired transmission lines being disposed adjacently and aligned in a longitudinal direction; an unbalanced transmission line for input or output of an unbalanced signal, the unbalanced transmission line being in parallel with the balanced transmission line and facing the balanced transmission line; and two lead transmission lines one of which is connected to one end portion of one of the paired transmission lines at a right angle to the one of the paired transmission lines, and the other of which is connected to one end portion of the other of the paired transmission lines at a right angle to the other of the paired transmission lines, the one end portion of the one of the paired transmission lines and the one end portion of the other of the paired transmission lines being neighboring two end portions of four end portions of the paired transmission lines, wherein the one of the two lead transmission lines has a first electrode face which faces the other of the two lead transmission lines, the other of the two lead transmission lines has a second electrode face which faces the one of the two lead transmission lines, and the first electrode face and the second electrode face are electrode faces of a capacitor.