In vitro and in vivo testing of a wireless multichannel stimulating telemetry microsystem

An inductively powered 64-site current microstimulating system, Interestim-2B, with a modular architecture and minimal number of off-chip components has been developed for neural prosthesis applications. Interestim-2B can generate any arbitrary current waveform and supports a variety of monopolar and bipolar stimulation protocols. A common analog line provides access to each site potential, and exhausts residual stimulus charges. In situ site impedance measurement capability helps indicate the defective sites in chronic stimulations. This paper also summarizes some of the in vitro and in vivo experimental results using a 16-site implant.