SAM4L Datasheet, PDF (52/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

ATSAM4L4/L2
6.1.5
Power Save Mode Summary Table
The following table shows a summary of the main Power Save modes:
Table 6-2. Power Save mode Configuration Summary
Mode
Mode Entry
Wake up sources
SLEEP
WFI
SCR.SLEEPDEEP bit = 0
BPM.PMCON.BKUP bit = 0
Any interrupt
WAIT
RETENTION
WFI
SCR.SLEEPDEEP bit = 1
BPM.PMCON.RET bit = 0
BPM.PMCON.BKUP bit = 0
WFI
SCR.SLEEPDEEP bit = 1
BPM.PMCON.RET bit = 1
BPM.PMCON.BKUP bit = 0
BACKUP
WFI
+ SCR.SLEEPDEEP bit = 1
+ BPM.PMCON.BKUP bit = 1
PM WAKE interrupt
PM WAKE interrupt
EIC interrupt
BOD33, BOD18 interrupt
and reset
AST alarm, periodic,
overflow
WDT interrupt and reset
external reset on RESET_N
pin
Core
domain
CPU clock OFF
Other clocks OFF depending
on the BPM.PMCON.SLEEP
field
see ”SLEEP mode” on page
48
All clocks are OFF
Core domain is retained
All clocks are OFF
Core domain is retained
OFF (not powered)
Backup
domain
Clocks OFF depending on
the BPM.PMCON.SLEEP
field
see ”SLEEP mode” on page
48
All clocks are OFF except
RC32K or OSC32K if
running
All clocks are OFF except
RC32K or OSC32K if
running
All clocks are OFF except
RC32K or OSC32K if
running
6.2 Power Scaling
The Power Scaling technique consists of adjusting the internal regulator output voltage (voltage
scaling) to reduce the power consumption. According to the requirements in terms of perfor-
mance, operating modes, and current consumption, the user can select the Power Scaling
configuration that fits the best with its application.
The Power Scaling configuration field (PMCON.PS) is provided in the Backup Power Manager
(BPM) module.
In RUN mode, the user can adjust on the fly the Power Scaling configuration
The Figure 6.1 summarizes the different combination of the Power Scaling configuration which
can be applied according to the Power Save Mode.
Power scaling from a current power configuration to a new power configuration is done by halt-
ing the CPU execution
Power scaling occurs after a WFI instruction. The system is halted until the new power configu-
ration is stabilized. After handling the PM interrupt, the system resumes from WFI.
To scale the power, the following sequence is required:
• Check the BPM.SR.PSOK bit to make sure the current power configuration is stabilized.
52
42023C–SAM–02/2013