QT1070 Detection Changes

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I have a QT1070 in I2C (Comms) Mode. I have connected a copper pad to the KEY4 pin (using suggested minimal trace width and 10k resistor near to the device).


I read out the NTHR value and key value. NTHR: 745, Key value reaches 800 when touched. It seems that when I touch the pad for the first time, it registers a touch (at approx. 790) but when I touch it again, the reading may go up to 810 but it doesn't register another touch.


I have:

DI: 2

Sensitivity: 10


I am contemplating just doing a comparison in the AVR MCU myself, but that would mean that I cannot use the CHANGE pin.


Any help / pointers would be greatfully appreciated,


Kind Regards.