Active Layer Protection

The RTC provides a mean of detecting broken traces on the PCB , also known as Active layer Protection. In this mode, a generated internal RTC signal can be directly routed over critical components on the board using RTC OUT output pin to one RTC INn input pin. A tamper condition is detected if there is a mismatch on the generated RTC signal.

The Active Layer Protection mode and the generation of the RTC signal is enabled by setting the RTCOUT bit in the Control B register (CTRLB.RTCOUT).

Enabling active layer protection requires the following steps: