A self-testing multiplexed CMOS stimulating probe for a 1024-site neural prosthesis

This paper describes a multiplexed silicon microprobe for selectively stimulating and recording in the central nervous system. The probe is used in a three-dimensional array and is designed as the basis for a fully-integrated neural prosthesis. CMOS circuitry delivers biphasic currents from -127 /spl mu/A to +127 /spl mu/A to selected sites with 1 /spl mu/A resolution. On-chip DACs operate with an integrated nonlinearity less than 0.2LSB while delivering an output voltage swing within 0.5 V of the (/spl plusmn/5 V) power rails. Simulataneous stimulation and recording is possible using on-chip preamplifiers having a gain 40 dB from 100 Hz to 10 kHz. In order to facilitate the microassembly of 3D arrays, the probe is designed to achieve full testability at the pre-release, post-release, and post-assembly levels.