A programmable output current source for use within an implantable tissue or nerve stimulator, e.g., an implantable cochlear stimulator or spinal cord stimulator, includes parallel-connected P-FET current source sets connected between a positive voltage rail and an electrode node, and parallel-connected...http://www.google.com.au/patents/US6181969?utm_source=gb-gplus-sharePatent US6181969 - Programmable current output stimulus stage for implantable device
