ATSAM3S ATMEL [ATMEL Corporation], ATSAM3S Datasheet - Page 19

• Manufacturer Part Number: ATSAM3S
• Description: AT91 ARM Cortex M3-based Processor
• Manufacturer: ATMEL [ATMEL Corporation]

5.4
5.5
5.5.1
6500AS–ATARM–11-Dec-09
Active Mode
Low Power Modes
Backup Mode
Figure 5-3.
Active mode is the normal running mode with the core clock running from the fast RC oscillator,
the main crystal oscillator or the PLLA. The power management controller can be used to adapt
the frequency and to disable the peripheral clocks.
The various low power modes of the SAM3S are described below:
The purpose of backup mode is to achieve the lowest power consumption possible in a system
which is performing periodic wake-ups to perform tasks but not requiring fast startup time
(<0.1ms). Total current consumption is 3 µA typical.
The Supply Controller, zero-power power-on reset, RTT, RTC, Backup registers and 32 kHz
oscillator (RC or crystal oscillator selected by software in the Supply Controller) are running. The
regulator and the core supply are off.
Backup mode is based on the Cortex-M3 deepsleep mode with the voltage regulator disabled.
The SAM3S can be awakened from this mode through WUP0-15 pins, the supply monitor (SM),
the RTT or RTC wake-up event.
Backup mode is entered by using WFE instructions with the SLEEPDEEP bit in the System Con-
trol Register of the Cortex-M3 set to 1. (See the Power management description in The ARM
Cortex M3 Processor section of the product datasheet).
Exit from Backup mode happens if one of the following enable wake up events occurs:
Main Supply
Backup Battery
Backup
Battery
IN
ON/OFF
3.3V
LDO
Note: The two diodes provide a “switchover circuit” (for illustration purpose)
between the backup battery and the main supply when the system is put in
backup mode.
+
-
OUT
External wakeup signal
ADC, DAC, Analog
Comparator Supply
(2.4V-3.6V)
VDDCORE
VDDIO
VDDPLL
VDDOUT
VDDIN
SAM3S Summary
PIOx (Output)
WAKEUPx
Analog Comp.
Transceivers.
Regulator
ADC, DAC
Voltage
USB
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