Abstract
A touch sensor is a grid of capacitors connected in a column and row matrix. A voltage pulse is placed on a row and the integrated voltage is measured on a column. When a finger is near the sensor, the column voltage decreases. Even though the change is small, this change can be used to determine when a finger is present. By determining which column and row combinations have changed, finger positions can be calculated. Even though mutual capacitance has several advantages over self capacitance, it can be helpful to perform both measurements.
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Gray, T. (2019). Measuring Capacitance. In: Projected Capacitive Touch. Springer, Cham. https://doi.org/10.1007/978-3-319-98392-9_4
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DOI: https://doi.org/10.1007/978-3-319-98392-9_4
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Publisher Name: Springer, Cham
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Online ISBN: 978-3-319-98392-9
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