The data filtering block follows the calibration unit. There are two kinds of filtering: one will discriminate against nearby keys touching and the other one will clean up the noise. The adjacent key suppression can be programmed by setting a register. The device can be programmed to sense only a single key, the one with the strongest change in impedance, the two keys with the strongest impedance change, or the impedance change on all keys. In this example, this provides flexibility in terms of how the actual application can be implemented in that the detection mode selected will be the one that best suits the application needs.