Capacitive sensor with reduced noise

摘要

A method includes actuating a drive electrode to couple a majority of charge to a first sense electrode, a dielectric panel overlying the drive electrode, the first sense electrode, and a second sense electrode. The sense electrodes are separated by coupling gaps, the second sense electrode shielded from the drive electrode by the first sense electrode. The first sense electrode and at least one of the drive electrode and the second sense electrode each include at least two electrode elements, which are arranged interleaved on the dielectric panel in the sequence: drive electrode element, first sense electrode element, second sense electrode element, first sense electrode element, drive electrode element. The method includes sampling the first and second sense electrodes to collect respective first and second signal samples, subtracting the second signal sample from the first signal sample to obtain a final signal, and outputting the final signal.

主权项

1. A method of capacitive touch sensing comprising:
actuating a drive electrode to couple a majority of charge from the drive electrode to a first sense electrode, a capacitive touch sensor comprising a dielectric panel overlying the drive electrode, the first sense electrode, and a second sense electrode, the first and second sense electrodes being separated by coupling gaps, the second sense electrode being positioned to be shielded from the drive electrode by the first sense electrode, wherein the first sense electrode and at least one of the drive electrode and the second sense electrode each comprise at least two electrode elements, and the electrode elements are arranged interleaved on the dielectric panel in at least one repeat of the sequence: drive electrode element, first sense electrode element, second sense electrode element, first sense electrode element, drive electrode element; sampling the first sense electrode to collect a first signal sample; sampling the second sense electrode to collect a second signal sample; subtracting the second signal sample from the first signal sample to obtain a final signal; and outputting the final signal.