Example implantable cardiac stimulation devices, pulse generators, and methods providing enhanced cardiac pacing energy are disclosed herein. In an example, an implantable cardiac stimulation device may include a pulse generator having a pacing output node providing cardiac pacing pulses to be applied to a heart of a patient. The pulse generator may include a pulse voltage regulator that receives a pacing signal and generates cardiac pacing pulses at an output of the pulse voltage regulator according to the pacing signal. The pulse voltage regulator may receive a supply voltage to generate cardiac pacing pulses at the supply voltage, gated by the pacing signal. The pulse generator may further include routing circuitry to route the output of the pulse voltage regulator to the pacing output node of the pulse generator while the pulse generator is in a first operating mode, and to route the supply voltage, gated by the pacing signal, to the pacing output node of the pulse generator while the pulse generator is in a second operating mode.