PURPOSE: To minimize the leakage of high frequency signals to a power supply input terminal by providing a power supply input terminal part where a high frequency absorber is inserted and an input/output terminal part for high frequency signals in response to the parts of a leakage preventing device which are partitioned in terms of high frequency.

CONSTITUTION: For instance, a high frequency absorber 4 of epoxy-iron, ferrite, etc. is inserted into a power supply input terminal 2 to absorb the high frequency signals to be applied to the terminal 2. For a package 3, an input/output terminal for high frequency signals and the terminal 2 are set opposite to each other on a package mounting surface of a leakage preventing device which is partitioned previously into a high frequency part 15 and a power supply circuit (bias circuit) 18 in terms of high frequency. In such a constitution of the package 3, the circuit 18 can be connected directly to the terminal 2. Thus, the leakage of high frequency signals to the power supply side is minimized.