6.6 Testing Active Layer Protection

The active layer protection feature of the RTC can be tested as mentioned below. The main function of Active layer protection is detecting the broken traces on the PCB.

• Active layer protection involves two pins called RTC/IN[n] and RTC/OUT for detecting tamper condition
• Connect one end of the PCB to the RTC/IN [n] pin and the other end (which has continuity with IN[n] pin) to the RTC/OUT pin
• Then define a known pattern of waveform to the RTC/IN[n] pin and generate the same pattern at the RTC/OUT pin and send it across the PCB routing
• If there are any broken traces in the PCB or someone is attempting to remove the PCB, this will cause a mismatch in the wave pattern at IN and OUT pins, which will trigger a tamper interrupt