CMOS current-copying neural stimulator with OTA-sharing

We present a compact current mode stimulator for utilization in neural stimulation arrays. The stimulator is implemented in a 0.35μm CMOS technology and occupies an area of 50μm×400μm. The memory in every current driver allows for simultaneous stimulation on multiple active channels when used as part of an array of stimulators. Circuit reuse in the stimulator and utilization of a single DAC yield a compact and low-power implementation. The current driver dissipates a quiescent power of 2.76μW. The stimulator can output current in the range of 10μA-250μA.