Datasheet

7
ATmega323(L)
1457E–11/01
External Clock To drive the device from an external clock source, XTAL1 should be driven as shown in
Figure 3.
Figure 3. External Clock Drive Configuration
External RC Oscillator For timing insensitive applications, the external RC configuration shown in Figure 4 can
be used. For details on how to choose R and C, see Table 73 on page 209.
Figure 4. External RC Configuration
Timer Oscillator For the Timer Oscillator pins, PC6(TOSC1) and PC7(TOSC2), the crystal is connected
directly between the pins. No external capacitors are needed. The oscillator is optimized
for use with a 32.768 kHz watch crystal. Applying an external clock source to
PC6(TOSC1) is not recommended.
XTAL2
XTAL1
GND
C
R
V
CC
NC