Semiconductor device

An object of the present invention is to provide a semiconductor device in which the collector current Ic of the output stage IGBT does not oscillate in the operating processes of a self shut down circuit and a current control circuit, and thus the ignition plug is prevented from erroneous ignition and the size of the device is minimized. A semiconductor device for ignition performing a current control function and a self shut down function comprises a pulse generating circuit 23, a switching circuit 22, and a current source circuit 21, the three circuits together generating pulse current that discharges a capacitor 44 in the self shut down process. This construction suppresses oscillation of collector current Ic of the output stage IGBT 4 in the operating processes of the current control circuit 3 and the self shut down circuit 17, thus preventing the ignition plug 11 from erroneous ignition. In addition, the discharge of the capacitor 44 in a pulsed mode allows down-sizing of the capacitor 44, which contributes to minimization of the semiconductor device.