Low-power implantable microsystem intended to multichannel cortical recording

We present in this paper an implantable massively parallel cortical data acquisition system. The proposed embedded mixed-signal (analog/digital) processing units are intended to be integrated on one chip, which will be flipped and connected on the top of a microelectrode array. Each channel is composed of a Chopper stabilized (CHS) low-power front-end to remove the 1/f noise, and a mixed-signal compression module using an analog wavelet transform (WT) processor that covers the entire neural signals bandwidth. The proposed front-end is based on a new rail-to-rail preamplifier topology and its circuit simulation under 0.18 μm CMOS process demonstrates a power dissipation less than 25 μW per channel. The main application of this medical device is to record action potentials evoked by visual stimuli, but it can be useful for several other cortical recording purposes.