Embodiments relate to a device for controlling delivery of stimulation signals, comprising: a stimulation delivery circuit； a monitoring component to monitor voltage supplied in at least one current-driven charge pulse via the stimulation delivery circuit； and a stimulation control component to control voltage supplied in at least one subsequent charge pulse based on the charge of the at least one charge pulse delivered by the stimulation delivery circuit. The device may further comprise a model generation component to generate an impedance model of stimulation electrodes in the stimulation delivery circuit, wherein the stimulation control component is configured to control the stimulation delivery circuit to deliver charge according to the impedance model.
