CHARGE-TRANSFER-BASED SIGNAL INTERFACE FOR DIFFERENTIAL CAPACITIVE SENSORS

Jorge E. Gaitán-Pitre, Ramon Pallas-Areny
Abstract:
We propose a circuit to directly connect a differential capacitive sensor to a microcontroller unit (MCU), which is based on the charge-transfer method and does not need any calibration component. The performance has been tested by emulating the differential capacitive sensor with discrete components. The major uncertainty sources are residual stray capacitances. The maximal deviation obtained, referred to the Full Scale Span (FSS), is ±4 % for sensors with nominal capacitance C0 = 100 pF, and ±0,6 % for sensors with C0 = 1 nF.
Keywords:
differential capacitive sensor, charge transfer, sensor-to-microcontroller interface, direct sensor interface
Download:
IMEKO-WC-2015-TC4-137.pdf
DOI:
-
Event details
Event name:
XXI IMEKO World Congress
Title:

Measurement in Research and Industry

Place:
Prague, CZECH REPUBLIC
Time:
30 August 2015 - 04 September 2015