Among transistors used in an analog circuit portion of the semiconductor device, particularly in a high frequency circuit, a power supply circuit, and a data demodulation circuit, and transistors used in a digital circuit portion (logic circuit portion), a gate length of a transistor in the analog circuit portion is not less than a gate length of a transistor in the digital circuit portion. As a result, when an excess voltage is supplied, voltage in the analog circuit with a long gate length is suppressed to prevent the damage of elements such as transistors in the digital circuit portion to which a signal is inputted from the analog circuit.