13.3.2.1.2 Brown-out Detector (BOD) Reset
The user must enable the Brown-out Detector (BOD). The BOD halts code execution when the voltage falls below a specified threshold, ensuring the required voltage for the oscillator to operate at the necessary application speed and preventing code corruption caused by low-voltage levels.
The BOD issues a System Reset, and is not released until the voltage level increases above the set threshold. The on-chip BOD circuit will monitor the VDD level during operation by comparing it to a fixed trigger level. The BOD Configuration (FUSE.BODCFG) fuse must select the trigger level for the BOD.