11.3.2.1 Sleep Modes
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.
- 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.
- Power Down
- Only the WDT and the PIT (component of the RTC) are active.
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* | ||
ADC/PTC | CLK_PER | X | X* | ||
PIT (RTC) | CLK_RTC | X | X | X | |
WDT | CLK_WDT | X | X | X | |
Oscillators | Main Clock Source | X | X* | ||
RTC Clock Source | X | X* | |||
WDT Oscillator | X | X | X | ||
Wake-Up Sources | INTn and pin change | X | X | X | |
TWI address match | X | X | X | ||
Periodic Interrupt Timer | X | X | X | ||
UART start of frame | X | X* | |||
ADC/PTC window | X | X* | |||
RTC interrupt | X | X* | |||
All other interrupts | X |
Note:
- X means active. X* indicates that the RUNSTBY bit of the corresponding peripheral must be set to enter active state.