atmega103 ATMEL Corporation, atmega103 Datasheet - Page 7

• Manufacturer Part Number: atmega103
• Description: Atmega103 8-bit With 128k Bytes Of In-system Programmable Flash
• Manufacturer: ATMEL Corporation

External Clock
Timer Oscillator
0945I–AVR–02/07
To drive the device from an external clock source, XTAL2 should be left unconnected
while XTAL1 is driven as shown in Figure 3.
Figure 3. External Clock Drive Configuration
For the Timer Oscillator pins, TOSC1 and TOSC2, the crystal is connected directly
between the pins. No external capacitors are needed. The Oscillator is optimized for use
with a 32,768 Hz watch crystal. Applying an external clock source to TOSC1 is not
recommended.
OSCILLATOR
EXTERNAL
SIGNAL
NC
XTAL2
XTAL1
GND
ATmega103(L)
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