(regulated) or 5.0V (USB/external voltage). The voltage is selectable using a jumper on the power selection header
J105
.
An on-board power switch is used to turn power to the ATmega4809 ON and OFF. This power switch is controlled by
the EDBG. When the kit is powered up, the EDBG reads the ID chip information from all connected Xplained Pro
extension boards and checks that they are compatible with the voltage selected by the power selection header
J105
.
If the selected voltage is within the connected extensions ranges, the switch will open. If not, the EDBG power LED
will blink rapidly and the switch will stay closed resulting in no power provided to ATmega4809, the on-board
peripherals, and the connectors.
CAUTION
As ATmega4809 Xplained Pro can be powered by 5.0V, care must be taken not to connect any Xplained
Pro extensions that do not support this voltage, doing so may result in permanent damage. Check the
respective extension kit's user guide to see which voltages are acceptable.
Info:
The EDBG reads the ID information from Xplained Pro extensions and controls the power switch
when the kit is powered up. This mechanism does not check hot-plugging of extension boards.
Figure 4-2. Power Supply Block Diagram
V
C
C
_P
5V
0
External 5V input
EDBG
ATmega4809
Regulator 3.3V
Power Select
(Jumper)
EDBG USB
Auto MUX
VCC_P3V3
Peripherals
VCC_TARGET
VCC_MCU
Power Switch
Jumper
T
A
R
G
E
T_
V
C
C
_
E
N
A
B
LE
Regulator 3.3V
Power source
Power switch/
Jumper/Header
Power converter
Power consumer
V
C
C
_E
D
B
G
J105
mikroBUS
™
Socket
JP
JP
P S
P S
J207
J204
HD
HD
J103
TARGET_VCC_ ENABLE
J209
J208
4.2
Connectors
4.2.1
Xplained Pro Standard Extension Headers
The Xplained Pro extension headers EXT1, EXT2, and EXT3 offer access to the I/O of the microcontroller to expand
the board, for example, by connecting extensions to the board. These headers are based on the standard Xplained
Pro extension header specification. The connections are shown in the table below. The headers have a pitch of 2.54
mm.
ATmega4809 Xplained Pro
Hardware User Guide
©
2020 Microchip Technology Inc.
User Guide
DS50002716C-page 12
