An IoT sensor platform for LED-based optical spectroscopy

Custom CMOS integrated circuits and commercial LEDs can be combined to build a compact system aimed at performing optical spectroscopy with reduced cost and low area consumption. This work presents a LED-based device capable of detecting different fingerprints of reflected or diffused light, employing LEDs for both transmitting (i.e., light source) and receiving (i.e., photo-detector) purposes. Two recently proposed low-power mixed-signal integrated circuits are employed, paving the way for an IoT device powered by a single battery cell. Experimental tests were conducted to evaluate the sensing capability of the proposed system.