title: A wireless integrated circuit for 100-channel charge-balanced neural stimulation.
abstract: The authors present the design of an integrated circuit for wireless neural stimulation, along with benchtop and in - vivo experimental results. The chip has the ability to drive 100 individual stimulation electrodes with constant-current pulses of varying amplitude, duration, interphasic delay, and repetition rate. The stimulation is performed by using a biphasic (cathodic and anodic) current source, injecting and retracting charge from the nervous system. Wireless communication and power are delivered over a 2.765-MHz inductive link. Only three off-chip components are needed to operate the stimulator: a 10-nF capacitor to aid in power-supply regulation, a small capacitor (< 100 pF) for tuning the coil to resonance, and a coil for power and command reception. The chip was fabricated in a commercially available 0.6- mum 2P3M BiCMOS process. The chip was able to activate motor fibers to produce muscle twitches via a Utah Slanted Electrode Array implanted in cat sciatic nerve, and to activate sensory fibers to recruit evoked potentials in somatosensory cortex.
authors.forename: B K
authors.initials: BK
authors.lastname: Thurgood
authors.forename: D J
authors.initials: DJ
authors.lastname: Warren
authors.forename: N M
authors.initials: NM
authors.lastname: Ledbetter
authors.forename: G A
authors.initials: GA
authors.lastname: Clark
authors.forename: R R
authors.initials: RR
authors.lastname: Harrison