ADVANCED COMMUNICATIONS & SENSING
Rev 0.9 – September 2010
22
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User’s Guide
SX8634/35/44/45 Evaluation Kit
Figure 21: two successive touches on button 0
- click on the stop button
on the Cap Sensor tab to go back to normal mode.
4.7 Sensitivity
The sensor sensitivity needs to be adapted to the thickness of the overlay, permittivity of the overlay, the size of the
buttons and detection thresholds.
The following shows a typical example of changing the sensitivity of the sensors using the EVK.
If the user touches button 0 as in the previous section then the sensor values are relatively large as the threshold is
passed with a lot off margin.
The sensitivity of a button can be modified easily in the Cap Sensors Tab.
Figure 22: sensitivity (5) of button 0
The default sensitivity for button 0 is five. A lower sensitivity would operate as well for button 0.
Going into monitor mode as described in the previous section is required to observe the sensor signal and
thresholds and hysteresis.
