Datasheet

36
8011K–AVR–09/08
ATmega164P/324P/644P
Note: 1. These options should only be used if frequency stability at start-up is not important for the
application.
Table 8-8. Start-up Times for the Low Frequency Crystal Oscillator Clock Selection
Power Conditions
Start-up Time from
Power-down and
Power-save
Additional Delay
from Reset
(V
CC
= 5.0V) CKSEL0 SUT1..0
BOD enabled 1K CK 14CK
(1)
000
Fast rising power 1K CK 14CK + 4.1 ms
(1)
001
Slowly rising power 1K CK 14CK + 65 ms
(1)
010
Reserved 0 11
BOD enabled 32K CK 14CK 1 00
Fast rising power 32K CK 14CK + 4.1 ms 1 01
Slowly rising power 32K CK 14CK + 65 ms 1 10
Reserved 1 11