A 32-site 3-D CMOS electronic interfaces to the nervous system

This paper discussed the design method of a 32 sites 3-D CMOS electronic interfaces to the nervous system. This interface is a kind of active silicon microelectrode biosensor which designed based on the MEMS technology. A new microstructure of active neural recording arrays system is presented, where two 2-D probes, one integrate circuits as well as two spacers are microassambled on a PCB platform. A theoretical measurement model for measuring the neural signal by the silicon microelectrode was proposed based on the structure and fabrication process of a single-shank probe. A block diagram of the on-chip circuitry is provided. Control data stream and Timing diagram for communication are discussed. The on-chip unity-gain bandpass amplifier has an overall gain of 42dB over a bandwidth from 60Hz to 10 kHz. The method of determining the dimensional parameters values of the probe shank is discussed in the following three aspects: the structure of pallium, efficient, coupled interconnects noise and strength characteristic of neural probe. The design criterion is to minimize the size of the neural probe when the probe has enough stiffness to pierce the endocranium.