| 摘要 |
PROBLEM TO BE SOLVED: To provide a balun that can be made compact by increasing isolation between balanced terminals, and to provide a power amplifier.SOLUTION: A first reactance element 21 and a second reactance element 22 having equivalent reactance components are connected in series between a first balanced terminal 12 and a second balanced terminal 13. A resistance element 23 has one end connected between the first reactance element 21 and second reactance element 22, and the other end grounded electrically. Consequently, the power due to an unwanted signal cinputted to the first balanced terminal 12 is consumed by the resistance element 23, and output of the unwanted signal cfrom the second balanced terminal 13 is suppressed. As a result, isolation between the first balanced terminal 12 and second balanced terminal 13 can be increased. Furthermore, the balun can be made more compact by eliminating the need for a distributed constant line having an electrical length equivalent to 1/2 of the wavelength of the unwanted signal c. |
