Clock Glitch Monitor

The system controller includes a clock glitch tamper detector that detects when the master clock input to the system controller is tampered in such a way to cause rapid change in frequency.

The monitor continuously monitors the clock period. Should if the period be significantly shorter or longer than the previous period, an error is reported. Small changes in period are ignored as the circuit delays vary due to PVT changes.

When an error occurs, the error is reported to the fabric through the tamper macro.