Patent ID: 8344457

Claim:
A transistor device comprising a protection diode device, comprising: a semiconductor substrate; a transistor formed on the semiconductor substrate; a gate pad electrode disposed on the semiconductor substrate and connected to the transistor; a source electrode disposed on and connected to the transistor; a first diode series comprising a plurality of pn junctions connected serially, one end of the first diode series being connected to the gate pad electrode and another end of the first diode series being connected to the source electrode; and a second diode series comprising a plurality of pn junctions connected serially, one end of the second diode series being connected to the gate pad electrode and another end of the second diode series being connected to the source electrode, wherein the first diode series and the second diode series are aligned along an edge of the semiconductor substrate, the edge extending in a first direction, and all of the pn junctions in the first diode series and the second diode series are aligned parallel in a second direction that is different from the first direction.