C3.1 - A Time-Based Capacitive to Digital Converter With Fast Data Acquisitions and High Resolution

Ali Heidary & Gerard C.M. Meijer
This paper presents an integrated interface with a fast data-accusation rate for capacitive sensor. Based on the results of an anlysis of the Charge-Transfer Process, the maximum frequency, for which the systematic errors are still within a certain limit, has been calculated. It is shown how the noise of the applied relaxation oscillator can be reduced by using a preamplifier with the minimum required bandwidth in front of the comparator. Further improvement is obtained by...