Determination of biological expression signals on a new handheld biochip-based microsystem

This paper presents techniques developed for the extraction of biological information in a recently developed hand-held biochip-based microsystem. The microsystem is based on a magneto-resistive array biochip composed of a number of sensing sites with magnetic tunnelling junctions (MTJ) and diodes. To drive the MTJ, different techniques are addressed with different types of signals. Different filtering strategies are also studied, which allow the recovery of bio signals from the noise without increasing too much the time required to access all the sensors, and the power consumption of the system. Finally, techniques to deal with the variability of fabrication parameters of the MTJ and of the diodes are addressed. In conclusion, experiments with the system in a setup to detect actual bio signals are presented with encouraging results.