A NOVEL SMART INTERFACE FOR VOLTAGE-GENERATING SENSORS

A novel low-cost smart interface for self-generating sensors, e.g., th ermopiles and thermocouples, is presented. The proposed interface acts as an asynchronous converter for de voltages employing a relaxation o scillator which output a period-modulated signal, A microcontroller is used to measure the output signal from the interface, to process data , and to output the measured sensor signal. The system provides an int rinsic A/D converter. Experimental results show that the interface is able to measure voltages in the range of 0 V to 5 V, with an accuracy and resolution of +/-64 x 10(-6) and 20 x 10(-6), respectively. The me asurement time is less than 100 ms.