A leadless cardiac pacemaker is provided which can include any number of features. In one embodiment, the pacemaker can include a tip electrode, pacing electronics disposed on a p-type substrate in an electronics housing, the pacing electronics being electrically connected to the tip electrode, an energy source disposed in a cell housing, the energy source comprising a negative terminal electrically connected to the cell housing and a positive terminal electrically connected to the pacing electronics, wherein the pacing electronics are configured to drive the tip electrode negative with respect to the cell housing during a stimulation pulse. The pacemaker advantageously allows p-type pacing electronics to drive a tip electrode negative with respect to the can electrode when the can electrode is directly connected to a negative terminal of the cell. Methods of use are also provided.
