An embodiment of an MOS device includes a semiconductor substrate of a first conductivity type, a first region of the first conductivity type having a length L.sub.acc and a net active dopant concentration of about N.sub.first, a pair of spaced-apart body regions of a second opposite conductivity type and each having a length L.sub.body and a net active dopant concentration of about N.sub.second, channel regions located in the spaced-apart body regions, source regions of the first conductivity type located in the spaced-apart body regions and separated from the first region by the channel regions, an insulated gate overlying the channel regions and the first region, and a drain region of the first conductivity type located beneath the first region. In an embodiment, (L.sub.body*N.sub.second)=k.sub.1*(L.sub.acc*N.sub.first), where k.sub.1 has a value in the range of about 0.6.ltoreq.k.sub.1.ltoreq.1.4.