ATmega168PB Xplained Mini User Guide [USER GUIDE]
42381A-MCU-10/2014
12
Table 2-8. J300 Board External Power Selection
J300
pin
Signal
Description
1
VCC_VBUS
VBUS Pin of USB Connector via fuse F100, by default connected to VCC_P5V0
via R300.
2
VCC_P5V0
Input voltage (4.3 to 16V) for the fixed-output voltage regulator (U300).
3
VCC_VIN
Alternative power source for the board (4.3 to 16V), study U300 data sheet for
detail requirements.
Table 2-9. J301 Board Power Supply Selection
J301
pin
Signal
Description
1
VCC_P5V0
Board external power source as selected by J300, by default connected to
VCC_BOARD via R301.
2
VCC_BOARD Power supply for ATmega32U4 and ATmega168PB.
3
VCC_P3V3
Board 3.3V power supply from U300.
2.3.7
Target SPI (J204)
The J204 header enable direct connection to ISP for programming of the ATmega168PB or to use the SPI bus
to connect external equipment.
Table 2-10. J204 SPI Header
J204 pin
Function
1
MISO
2
VCC target (ATmega168PB)
3
SCK
4
MOSI
5
RESET
6
GND
2.3.8
Additional Target Signals
Signals not available in any of the headers or connectors are available in column 5.
