AN EMBEDDED SYSTEM BASED ON A IC FOR NEURAL IMPEDANCE MEASUREMENT

摘要

In this paper a system aimed at measuring the impedancernin a neural interface is presented. The device core is anrnIntegrated Circuit (IC) realized in a CMOS 0.35 μm tech-rnnology. It includes eight different channels allowing to in-rndependently measure the impedance of multi-channel elec-rntrodes. The IC is composed of two main parts: a currentrngenerator based on a DAC and a sigma delta converter forrnneural recording. The device has been designed, realizedrnand successfully tested by means of electrical tests. It oc-rncupies an area of 3:7mm×4:1mm and consumes an over-rnall power of 16mW, the device can measure the impedancernboth in DC and in AC mode and can be configured in tworndifferent operating modes, covering an overall impedancernrange from 10kΩ to 100kΩ.