Figure 6-1. Power Supply - Kit Revision 5, 4, and 3
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
ON/OFF
Regulator 3.3V
Power source
Power switch
Power converter
Power consumer
V
C
C
_E
D
B
G
J105
mikroBUS
™
Socket
Work Around
Bypassing the power switch shown in the block diagram above will prevent the power-up problems. The work around
is to short-circuit J105 pin 2 and J103 pin 2, as shown in the image below.
WARNING
This work around removes the Xplained Pro extension overvoltage protection feature. Make sure that the
electrical specifications of the connected Xplained Pro extensions match the voltage configuration of the
ATmega4809 Xplained Pro (e.g., do not connect an Xplained Pro extension that does not support 5V to an
ATmega4809 Xplained Pro in a 5V configuration).
Figure 6-2. Power Supply Work Around
Revision 5 of ATmega4809 Xplained Pro already implements this hotfix.
Affected Kit Revisions
This design flaw affects revision 3, 4, and 5 of ATmega4809 Xplained Pro.
ATmega4809 Xplained Pro
Hardware Revision History and Known Issues
©
2020 Microchip Technology Inc.
User Guide
DS50002716C-page 26
