Design of self powered chip integrated humidity sensor

This paper presents a low power wireless capacitive based CMOS humidity sensor to be used in Internet of Things (IoT)applications, powered through inductive coupling. The sensing element is implemented in standard CMOS technology with minimum post processing step. This sensor is based on the detection of change in frequency due to the change in humidity levels. The proposed humidity sensor is designed in 0.18μm Global Foundries process. The simulated results show that even a change of as small as 50fF in the sensing element is detected, indicating high sensitivity. This chip consumes around 600μW of total power at 1.5V.