An auto-balancing capacitance-to-pulse-width converter for capacitive sensors

A novel auto-balancing capacitance-to-pulse- width converter (CPC) that uses sinusoidal excitation, and operates in a closed-loop configuration, is presented in this paper. Unlike most of the existing CPCs, the proposed interface circuit is compatible with both single-element and differential capaci...

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Detalles Bibliográficos
Autores: Areekath, Lakshmi, George, Boby, Reverter Cubarsí, Ferran|||0000-0003-1653-0519
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/361651
Acceso en línea:https://hdl.handle.net/2117/361651
https://dx.doi.org/10.1109/JSEN.2020.3014206
Access Level:acceso abierto
Palabra clave:Detectors
Capacitive sensor
Differential capacitive sensor
Pulse-width converter
Duty cycle
Sine wave
Auto- balancing
Digitizer
Linearization
PWM
Linear output
Parasitic capacitance
Àrees temàtiques de la UPC::Enginyeria electrònica::Instrumentació i mesura::Sensors i actuadors
Descripción
Sumario:A novel auto-balancing capacitance-to-pulse- width converter (CPC) that uses sinusoidal excitation, and operates in a closed-loop configuration, is presented in this paper. Unlike most of the existing CPCs, the proposed interface circuit is compatible with both single-element and differential capacitive sensors. In addition, it provides a pulse-width modulated (PWM) signal which can easily be digitized using a counter. From this PWM signal, a ratio output is derived when a single-element sensor is interfaced, and a ratiometric output is obtained for a differential sensor.