Abstract: Inter power supply surge voltage transmitting diode element is formed by a buried layer formed in a semiconductor substrate, a well region formed on the buried layer with its bottom portion being in contact with the buried layer, and impurity regions of mutually different conductivity types formed apart from each other at the surface of the well region. One of the impurity regions is electrically coupled to a first power supply line on which a surge voltage generates, and the other is electrically coupled to a second power supply line absorbing the surge voltage. The surge transmitting element includes a plurality of elements arranged parallel to each other between the first and second power supply lines. The second power supply line supplies the power supply voltage to an internal circuitry which consumes relatively small current.