An auditory nerve stimulation chip with integrated AFE, sound processing, and power management for fully implantable cochlear implants

This paper presents a system on chip for a fully implantable cochlear implant. It includes acoustic sensor frontend, 4-channel digital sound processing and auditory nerve stimulation circuitry. It also features a digital, switched mode, single inductor dual output power supply that generates two regulated voltages; 0.4 V used to supply on-chip digital blocks and 0.9 V to supply analog blocks and charge the battery when an external RF source is detected. All passives are integrated on-chip including the inductor. The system was implemented in 14nm CMOS and validated with post layout simulations.