AT42QT1010
Electrode trace routing: Keep the electrode trace (and the electrode itself) away from other
signal, power, and ground traces including over or next to ground planes. Adjacent switching
signals can induce noise onto the sensing signal; any adjacent trace or ground plane next to, or
under, the electrode trace will cause an increase in Cx load and desensitize the device.
Important Note: for proper operation a 100 nF (0.1 µF) ceramic bypass capacitor must be
used directly between Vdd and Vss, to prevent latch-up if there are substantial Vdd
transients; for example, during an ESD event. The bypass capacitor should be placed
very close to the Vss and Vdd pins.
4.4
Power On
On initial power up, the QT1010 requires approximately 100 ms to power on to allow power
supplies to stabilize. During this time the OUT pin state is not valid and should be ignored.
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9541G–AT42–03/10
ATMEL [ ATMEL ]
