Apparatus and method assure the electrical characteristics of a stimulation waveform to an electrode of an Implantable Neuro Stimulator. The embodiment comprises a regulator, a measurement module, a generator, and a processor. The generator provides an input signal to the regulator. The regulator consequently regulates the input signal in order to form a pulse that is applied to the electrode. The processor instructs the measurement module to perform an electrical measurement that is indicative of an amplitude of the pulse. If the electrical measurement is sufficiently different from a desired value, the processor instructs the generator to be reconfigured in order that the amplitude of the pulse is within an acceptable value. A redundant capacitor pair may be inserted in a capacitor arrangement in order to compensate for a reduced battery voltage, or a detected faulty component such as a capacitor or a regulator may be replaced with a redundant component.