A system for providing stimulation current in implantable medical devices
is provided. One aspect of this disclosure relates to an apparatus
including a power supply terminal adapted to be connected to a power
supply. The apparatus embodiment also includes circuitry connected to the
power supply terminal and adapted to detect a parameter dependent on
tissue/electrode impedance. The apparatus embodiment further includes a
current output pulse generator adapted to deliver electrical therapy. The
current generator includes an adjustable compliance voltage source
connected to the power supply terminal. The compliance voltage source has
a programmable amplitude and is adapted to provide different potentials
for different tissue/electrode interface impedances. According to various
embodiments, the apparatus embodiment also includes at least one
stimulating electrode, and the current generator is adapted to deliver
electrical therapy using the electrode. Other aspects and embodiments are
provided herein.