SEMICONDUCTOR DEVICE

PURPOSE:To increase the withstanding voltage only for an element, to which high withstanding voltage is required, by dividing a low withstanding voltage circuit and the high withstanding-voltage element in a semiconductor device in which the low withstanding voltage circuit and the high withstanding voltage element are juxtaposed with each other. CONSTITUTION:A signal system circuit 2 at low withstanding voltage is constituted by transistors (Tr) 6, 8, 10 and a resistor 12, base currents in the Tr10 are drawn on the basis of input signal currents applied to an input terminal 14, and a Tr4 is driven. An emitter is connected to a positive side line, on which a power supply terminal 16 to which positive voltage VE is applied is formed, in the PNP type Tr4 for an output driver as a high withstanding voltage element, and an output terminal 18 is shaped to a collector in the Tr4. The signal system circuit 2 and the Tr4 are divided and constituted, and the signal system circuit 2 has low withstanding voltage constitution and the Tr4 high withstanding voltage constitution. That is, the mutual distances among a collector section, an emitter section and a base section are lengthened in the Tr4 while distances among these three sections and an isolation region are increased.