ATMEGA8U2_14 Datasheet, PDF (187/310 Pages) ATMEL Corporation – 125 Powerful Instructions – Most Single Clock Cycle Execution

ATmega8U2/16U2/32U2
Figure 20-4. Typical Bus powered application with 3.3V I/O
VBUS
UDM
UDP
UVSS
VCC
AVCC
UCAP
1µF
UVCC
D+
D-
UVSS
VSS
XTAL1
XTAL2
20.3.2
Self Powered device
Figure 20-5. Typical Self powered application with 4.0V to 5.5V I/O.
External 3.4V - 5.5V
Power Supply
1µF
VBUS
UDP
UDM
UVSS
Rs=22
Rs=22
UID
UVCC
UCAP
AVCC
VCC
VBUS
D+
D-
UGND
UID
XTAL1
XTAL2
GND
GND
7799D–AVR–11/10
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