| 摘要 |
PROBLEM TO BE SOLVED: To overcome the problem such that it is difficult to obtain isolation trap with completely the same frequencies since a capacitor and an inductor constituting a trap circuit are different, and therefore the fluctuation of manufacture is generated even at the time of making their design the same at the first transmission path side and second transmission path side of a conventional IC switch for switching a signal to the two system transmission paths, and that a difference for the inductance is made large when the length of bonding wires is different. SOLUTION: The source sides of a third FET 63 and a fourth FET 64 at a ground side are connected to each other, and then connected to a common capacitor C11. Moreover, the capacitor C11 is connected to a common bonding pad (12), and connected through a common bonding wire (13) to a common external lead (14). Thus, the trap circuit is constituted of the common capacitor C11 and a common inductor L11 so that the trap frequencies can be made completely the same, and that high isolation can be obtained. |
