User's Manual

• If the host is not able to provide the requested current, the enumeration fails. Therefore, the U5 power
switch STMPS2151STR remains OFF and the MCU part including the extension board is not powered. As
a consequence, the LED5 green LED remains turned OFF
. In this case, it is mandatory to use an external
power supply.
Caution: If the maximum current consumption of the STM32WL Nucleo-64 board and its shield boards exceeds 300 mA,
it is mandatory to check the root cause of the overconsumption, and consequently, if needed, to power the
STM32WL Nucleo-64 board with an external power supply connected to VIN, 5 V or 3.3 V.
External power supply input from VIN (7 to 12 V, 800 mA maximum)
When the STM32WL Nucleo-64 board is power-supplied by VIN (refer to Table 6 and Figure 12), the jumper
configuration must be the following: jumper JP4 [3‑4] on 5V_VIN.
The STM32WL Nucleo-64 board and its shield boards can be powered in three different ways from an external
power supply, depending on the voltage used. The three cases are summarized in Table 6.
Table 6. External power sources: VIN (7 to 12 V)
Input power
name
Connector
pins
Voltage range
Maximum
current
Limitation
VIN
CN6 pin 8
CN7 pin 24
7 to 12 V 800 mA
From 7 to 12 V only and input current capability is
linked to input voltage:
•
800 mA input current when VIN = 7 V
• 450 mA input current when 7 V < VIN < 9 V
• 250 mA input current when 9 V < VIN < 12 V
Refer to Section 6.4.1 for debugging when using an external power supply
.
UM2592
Power supply
UM2592 - Rev 2
page 18/50