After the initialization of the sensors, the device starts with Active Measurement mode, by default. If there is no touch activity detected for 20 seconds, the device automatically switches to Low-Power mode. Before switching to Low-Power mode, the Event System is enabled, and the designated sensor is configured as a low-power sensor. This application demo uses all the channels lumped together, as a single node (Node_8), as a low-power sensor. This enables the microcontroller to wake-up from touch on the entire surface.
For more information on implementing the low-power touch application using PTC, refer to the Low-Power Touch Design guide. Table 7-2 shows the parameters configured for low-power touch detection.
| Parameter | Value |
|---|---|
| Low-power/Auto-scan key | Lump node 8 |
| Lump node X-lines | X21, X16, X6, X17 |
| Lump node Y-lines | Y22, Y5, Y23, Y4 |
| Lump node charge share delay | 0 |
| Low-power measurement period | 64 ms |
| Touch inactivity time-out | 20s |
| Drift measurement period | 5s |