In addition to Active mode, there are three different sleep modes, with
decreasing power consumption and functionality.
- Idle
- The CPU stops executing code, no peripherals are disabled.
- All interrupt sources can wake the device.
- Standby
- The user can configure peripherals to be enabled or not, using the
respective RUNSTBY bit. This means that the power consumption is highly
dependent on what functionality is enabled, and thus may vary between the Idle
and Power-Down levels.
- SleepWalking is available for the ADC module.
- Power-Down
- BOD, WDT, and PIT (a component of the RTC) are
active.
- The only wake-up sources are the pin change interrupt, PIT, VLM,
TWI address match and CCL.
Table 1. Sleep Mode Activity
Overview
| Group |
Peripheral |
Active in Sleep
Mode |
| |
Clock |
Idle |
Standby |
Power-Down |
| Active Clock Domain |
CPU |
CLK_CPU |
|
|
|
| Peripherals |
CLK_PER |
X |
|
|
| RTC |
CLK_RTC |
X |
X(1) |
|
| CCL |
CLK_PER(2) |
X |
X(1) |
|
| ADCn |
CLK_PER |
X |
X(1) |
|
| TCBn |
CLK_PER |
X |
X(1) |
|
| PIT (RTC) |
CLK_RTC |
X |
X |
X |
| BOD (VLM) |
CLK_BOD |
X |
X |
X |
| WDT |
CLK_WDT |
X |
X |
X |
| Oscillators |
Main Clock Source |
X |
X(1) |
|
| PIT and RTC Clock Source |
X |
X(1) |
X(3) |
| BOD Oscillator |
X |
X |
X |
| WDT Oscillator |
X |
X |
X |
| Wake-Up Sources |
INTn and Pin Change |
X |
X |
X |
| TWI Address Match |
X |
X |
X |
| PIT (RTC) |
X |
X |
X |
| CCL |
X |
X(1) |
X(4) |
| RTC |
X |
X(1) |
|
| UART Start-of-Frame |
X |
X(1) |
|
| TCBn |
X |
X(1) |
|
| ADCn Window |
X |
X(1) |
|
| ACn |
X |
X(1) |
|
| All other Interrupts |
X |
|
|
Note:
- 1.RUNSTBY bit of the corresponding peripheral must be set to enter the active
state.
- 2.CCL can select between multiple clock sources.
- 3.PIT only
- 4.CCL can wake up the device if no internal clock source is required.