The 3.3V Brown-Out Detector (BOD33) is able to monitor the VDD supply and compares the voltage with the brown-out threshold level set in the BOD33 Level field (BOD33.LEVEL) in the BOD33 register.
When VDD crosses below the brown-out threshold level, the BOD33 can generate either an interrupt or a Reset, depending on the BOD33 Action bit field (BOD33.ACTION).
The BOD33 detection status can be read from the BOD33 Detection bit in the Status register (STATUS.BOD33DET).
At start-up or at Power-On Reset (POR), the BOD33 register values are loaded from the NVM User Row.