Patent ID: 7187033

Claim:
A drain-extended MOS transistor, comprising: a source of a first conductivity type formed in a semiconductor body; a drain of the first conductivity type laterally spaced from the source in the semiconductor body; a drift region of the first conductivity type located between the drain and the source in the semiconductor body; a channel region of a second conductivity type extending between the drift region and the source in the semiconductor body, wherein the drift region extends between the channel region and the drain; a gate located above the channel region; a first buried layer of the first conductivity type located below the source, the channel region, and the drift region, the first buried layer being separated from the drift region and from the drain; a diode having an anode coupled with the first buried layer and a cathode coupled with at least one of the drift region and the drain; and a second buried layer of the second conductivity type located below the source, the channel region, and the drift region, wherein the second buried layer separates the first buried layer from the drain and the drift region, and wherein the diode is separated from and not directly coupled to the second buried layer.