Rainbow Electronics ATmega161L - Manual (Page 6)

6
ATmega161(L)
1228C–AVR–08/02
Crystal Oscillator XTAL1 and XTAL2 are input and output, respectively, of an inverting amplifier that can
be configured for use as an on-chip Oscillator, as shown in Figure 2. Either a quartz
crystal or a ceramic resonator may be used. To drive the device from an external clock
source, XTAL2 should be left unconnected while XTAL1 is driven as shown in Figure 3.
Figure 2. Oscillator Connections
Figure 3. External Clock Drive Configuration
XTAL2
XTAL1
GND
C2
C1
XTAL2
XTAL1
GND
NC
EXTERNAL
OSCILLATOR
SIGNAL