Datasheet

Power Supply Reset. When VDD crosses above the brown-out threshold level (BOD33.LEVEL), the
device will leave battery backup mode and will wakeup from backup mode if the BBPS.WAKEEN bit is
set.
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.
Related Links
9.4 NVM User Page Mapping
19.6.5.3.1 BOD33 Sampling Mode
The Sampling Mode is a low-power mode where the BOD33 is being repeatedly enabled on a sampling
clock’s ticks. The BOD33 will monitor the supply voltage (VDD or VBAT) for a short period of time and
then go to a low-power disabled state until the next sampling clock tick.
Sampling mode is enabled in Backup or Hibernate mode by writing to the BOD33 bits (BOD33.BKUPCFG
= 1 or BOD33.HIBCFG = 1). The frequency of the clock ticks (F
clksampling
) is controlled by the Prescaler
Select bit groups in the BOD33 register (BOD33.PSEL).


=


2
PSEL+1
The prescaler signal (F
clkprescaler
) is a 32 kHz clock, output by the 32 kHz Ultra Low-Power Oscillator
OSCULP32K.
Note: If (BOD33.PSEL) is 0, sampling mode is disabled.
As the sampling clock is different from the APB clock domain, synchronization among the clocks is
necessary. See 19.6.7 Synchronization for additional information.
Related Links
9.4 NVM User Page Mapping
19.6.5.3.2 BOD33 Low Power Mode
BOD33 Low Power mode is automatically enabled in Backup or Hibernate sleep mode.
BOD33 Low Power mode can be enabled in Standby sleep mode by writting to '1' the
BOD33.STDBYCFG bit.
Related Links
9.4 NVM User Page Mapping
19.6.5.3.3 BOD33 Hysteresis
A hysteresis on the trigger threshold of a BOD will reduce the sensitivity to ripples on the monitored
voltage: instead of switching RESET at each crossing of V
BOD
, the thresholds for switching RESET on
and off are separated (V
BOD-
and V
BOD+
, respectively).
Figure 19-2. BOD Hysteresis Principle
Hysteresis OFF:
SAM D5x/E5x Family Data Sheet
SUPC – Supply Controller
© 2019 Microchip Technology Inc.
Datasheet
DS60001507E-page 242