A semiconductor device, according to one possible configuration, includes switching circuits, each switching circuit comprising IGBT chips connected in series and clamping diodes. The semiconductor device also includes a first and a second wiring line and auxiliary emitter lines. The first wiring line and a first auxiliary emitter line connect the emitter terminals of IGBT chips of the first and second switching circuits. The second wiring line and another auxiliary emitter line connect the emitter terminals of the third IGBT chips of the first and second switching circuits. The wiring lines have a large current carrying capacity and a lower resistance value than their respectively connected auxiliary emitter line.