11.3.2.2 Wake-Up Time
- In Idle sleep mode the Main Clock source is kept running so it will not be any extra wake-up time.
- In Standby sleep mode the Main Clock might be running, so it depends on the peripheral configuration.
- In Power Down sleep mode only the ULP 32KHz oscillator and RTC clock may be running, if it is used by the BOD or WDT. All other clock sources will be off.
Sleep mode | Start-up time |
---|---|
IDLE | 6 CLK |
Standby | 6 CLK + OSC start-up |
Power Down | 6 CLK + OSC start-up |
In addition to the normal wake-up time it is possible to make the device wait until the BOD is ready before executing code. This is done by writing 0x3 to the BOD Operation Mode in Active and Idle bits (ACTIVE) in the BOD Configuration fuse (FUSE.BODCFG). If the BOD is ready before the normal wake-up time, the net wake-up time will be the same. If the BOD takes longer than the normal wake-up time, the wake-up time will be extended until the BOD is ready. This is ensures correct supply voltage whenever code is executed.