Patent attributes
A semiconductor device includes a first external electrode with a first electrode surface portion; a second external electrode with a second electrode surface portion; a MOSFET chip with a built-in Zener diode which includes an active region and a peripheral region; a control IC chip which drives the MOSFET chip based on voltage or current between a drain electrode and a source electrode of the MOSFET chip; and a capacitor which supplies power to the MOSFET chip and the control IC chip. The first electrode surface portion is connected to either the drain electrode or the source, the second electrode surface portion is connected to either the source electrode or the drain electrode, a plurality of unit cells of the MOSFET with the built-in Zener diode are provided in the active region, and the breakdown voltage of the Zener diode is set to be lower than that of the peripheral region.