The semiconductor integrated circuit (RF IC) for a mobile telephone capable of transmitting/receiving the signals of plural bands reduces the DC offsets of the amplifiers located in the following stages of the mixers that demodulate or down-convert the reception signals. The invention scrambles the signal lines to transmit the outputs of the plural mixers that demodulate or down-convert the reception signals of different bands, so as to avoid the adjacent signal lines from making the same combination from the starting ends to the finishing ends.