A MULTI PROCESSOR CONTROL SYSTEM FOR A GAS SENSING ARRAY

Nowadays microsystems based on gas sensing arrays with suitable electronic interfaces are being increasingly adopted for monitoring the presence of pollutant gases in the air (e.g. CO, C6&, NOz). The system described in this paper controls and acquires data from a gas sensor which exploits an array of four metal-oxide thin films deposited on thin dielectric membranes. The system is based on a microcontroller local network. An advantage of this architecture is the modularity of the system. A multisensor system is preferred because a single sensor does not react selectively to a singular target gas inside a mixture, but also to other interfering gases, therefore sensor redundancy helps in improving the performance of the gas detector.