A Mixed-Signal Multi-Chip Neural Recording Interface with Bandwidth Reduction

We present the design of a multi-chip neural interface intended for multi-channel neural recording. The design features a mixed-signal part that handles neural signal conditioning, digitization and time-division multiplexing, and a digital part that provides control, bandwidth reduction, and serial communications towards a host interface. The two CMOS 0.18-μm fabricated embedded circuits that implement both parts are directly mounted on the back of a medical-grade stainless steel microelectrodes array and wire-bonded to its post-processed base. The presented neural interface integrates 16 channels for validation; however, the proposed approach is scalable to larger channel counts. In fact, it is suitable to implement microsystems including several hundreds of recording channels. The performance of the implemented multi-channel interface was validated with real neural waveforms.