SAM3U Datasheet, PDF (18/59 Pages) ATMEL Corporation – AT91SAM ARM-based Flash MCU

Figure 5-3. Backup Batteries Used
FWUP
SHDN
Backup Batteries ^VDDBU
VDDUTMI
VDDANA
VDDIO
Main Supply (1.62V-3.6V)
VDDIN
VDDOUT
Voltage
Regulator
VDDCORE
VDDPLL
Note:
Restrictions
With Main Supply < 2.0 V, USB and ADC are not usable.
With Main Supply ≥ 2.4V and < 3V, USB is not usable.
With Main Supply ≥ 3V, all peripherals are usable.
18 SAM3U Series
6430ES–ATARM–22-Aug-11