Semiconductor integrated circuit device with crosstalk prevention

A semiconductor integrated circuit device, comprising:

• a large scale cell array;
• a wiring which is formed in a first region within which the large scale cell array is formed, in which the wiring transfers a first signal which has a level needed for an operation of the large scale cell array and is used in the large scale cell array;
• a through wiring which passes through the first region, in which the through wiring transmits a second signal which is smaller in level than the first signal;
• an input buffer circuit which is connected to one end of the through wiring at a boundary between the first region and a second region within which the large scale cell array is not formed, the first signal transmitted from the second region being inputted into the input buffer, wherein said input buffer converts the level of the first signal to a smaller level, and outputs and transmits the second signal to the first region;
• and
• an output buffer circuit which is connected to the other end of the through wiring at the boundary, in which the second signal is directly input to said output buffer circuit without being used in the large scale cell array, wherein said output buffer circuit converts a level of the second signal to a large level, and outputs an transmits a third signal to the second region.