Abstract
This paper presents an ultra-low-power, widedynamic-range interface circuit for capacitive and resistive sensors. The circuit is implemented as a switched-capacitor circuit using programmable capacitors to achieve high configurability. The circuit was fabricated using a CMOS 0.18 μm process. Different types of capacitive and resistive sensors were measured using the interface to demonstrate its support for multi-sensor systems with an ultra-low-power budget. Experimental results show that the circuit is able to interface various sensors within the overall capacitance range of 0.6-550 pF and resistance range of 3.7-5100 kΩ, while consuming only 0.39-3.56 μW from a 1.2 V supply. A proximity, gesture, and touch-sensing system is also developed consisting of the designed interface circuit and a sensor element that is able to detect the displacement of an object up to 15 cm from the sensing electrodes consuming only 0.83 μW from a 1.2 V supply.
Highlights
S ENSORS are one of the key elements for enabling emerging technologies such as internet of things (IoT) and ambient intelligence (AmI) [1]–[4]
MEASUREMENT RESULTS The universal multi-sensor interface (UMSI) chip was fabricated in a 0.18 μm CMOS process with a total area of 1.89 mm2 including the pads
The supply domains were connected together off-chip. Sensitive signal paths such as the capacitive sensor element nodes were protected by surrounding them with ground paths
Summary
S ENSORS are one of the key elements for enabling emerging technologies such as internet of things (IoT) and ambient intelligence (AmI) [1]–[4]. In IoT and AmI environments we are surrounded by embedded intelligent objects that sense different quantities of our physical surroundings. As IoT and AmI develop rapidly, there is an increasing demand for microsystems that are equipped with various types of sensors. IoT devices are typically battery-powered or rely on harvesting energy from their environment, limiting their power. Date of publication June 2, 2020; date of current version September 17, 2020. An earlier version of this article was presented at the IEEE International Symposium on Circuits and Systems, Florence, Italy, May 2018. The associate editor coordinating the review of this article and approving it for publication was Prof.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
