20.3.3 Sleep Mode Operation

The BOD configuration in the different sleep modes is defined by fuses. The mode used in Active mode and Idle sleep mode is defined by the ACTIVE fuses in FUSE.BODCFG, which is loaded into the ACTIVE bit field in the Control A (BOD.CTRLA) register. The mode used in Standby sleep mode and Power-Down sleep mode is defined by SLEEP in FUSE.BODCFG, which is loaded into the SLEEP bit field in the Control A (BOD.CTRLA) register.

The operating mode in Active mode and Idle sleep mode (i.e., ACTIVE in BOD.CTRLA) cannot be altered by software. The operating mode in Standby sleep mode and Power-Down sleep mode can be altered by writing to the SLEEP bit field in the Control A (BOD.CTRLA) register.

When the device is going into Standby or Power-Down sleep mode, the BOD will change the operation mode as defined by SLEEP in BOD.CTRLA. When the device is waking up from Standby or Power-Down sleep mode, the BOD will operate in the mode defined by the ACTIVE bit field in the Control A (BOD.CTRLA) register.