Datasheet
27
ATmega48/88/168 Automotive [DATASHEET]
7530K–AVR–07/14
Figure 6-3. Crystal Oscillator Connections
Table 6-6. Start-up Times for the Full Swing Crystal Oscillator Clock Selection
Oscillator Source / Power
Conditions
Start-up Time from Power-
down and Power-save
Additional Delay from
Reset (V
CC
= 5.0V) CKSEL0 SUT1..0
Ceramic resonator, fast rising
power
258CK 14CK + 4.1ms
(1)
0 00
Ceramic resonator, slowly rising
power
258CK 14CK + 65ms
(1)
0 01
Ceramic resonator, BOD enabled 1KCK 14CK
(2)
0 10
Ceramic resonator, fast rising
power
1KCK 14CK + 4.1ms
(2)
0 11
Ceramic resonator, slowly rising
power
1KCK 14CK + 65ms
(2)
1 00
Crystal Oscillator, BOD enabled 16KCK 14CK 1 01
Crystal Oscillator, fast rising
power
16KCK 14CK + 4.1ms 1 10
Crystal Oscillator, slowly rising
power
16KCK 14CK + 65ms 1 11
Notes: 1. These options should only be used when not operating close to the maximum frequency of the device, and
only if frequency stability at start-up is not important for the application. These options are not suitable for
crystals.
2. These options are intended for use with ceramic resonators and will ensure frequency stability at start-up.
They can also be used with crystals when not operating close to the maximum frequency of the device, and if
frequency stability at start-up is not important for the application.
C2
XTAL2
XTAL1
GND
C1