This paper presents a computational study on linearizing technique using ADC for a capacitive sensor based humidity measurement system. A VALVO 2322691 90001 humidity sensor has been considered to be placed in one arm of an AC bridge, the output voltage after AC-to-DC conversion, being fed to an ADC with additional circuitry so that the task of digitization and quasi-linearization are carried out simultaneously. Computations have been carried out over the entire span of relative humidity (0% to 100%). The linearizing coefficient has been determined by three different methods. The necessity of tuning the coefficient to a suitable value depending on the range of relative humidity covered and the permissible limit of non-linearity, has been pointed out.
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