A transistor module assembly includes a longitudinally extending load bus bar, a longitudinally extending feed bus bar parallel to the load bus bar, and at least one transistor package operatively connected to the load and feed bus bars. The transistor package includes a drain surface and a source lead. The drain surface is operatively connected to the feed bus bar for receiving current therefrom. The source lead is operatively connected to the load bus bar for dissipating current from the transistor package to the load bus bar.