UM1724 Rev 14 21/68
UM1724 Hardware layout and configuration
67
6.3.2  External power supply inputs: VIN and E5V
The external power sources VIN and E5V are summarized in Table 7. When the board is 
power supplied by VIN or E5V, the jumpers configuration must be the following:
• Jumper on JP5 pin 2 and pin 3
• Jumper removed on JP1
 
 
Using VIN or E5V as external power supply
VIN or E5V can be used as an external power supply in case the current consumption of the 
STM32 Nucleo and extensions boards exceeds the allowed current on USB. In this 
condition, it is still possible to use the USB for communication, for programming or 
debugging only, but it is mandatory to power supply the board first using VIN or E5V then 
connect the USB cable to the PC. Proceeding this way ensures that the enumeration occurs 
thanks to the external power source. 
The following power sequence procedure must be respected: 
Table 7. External power sources 
Input 
power name
Connectors 
pins
Voltage 
range
Max 
current
Limitation
VIN
CN6 pin 8 
CN7 pin 24
7 V to 12 V 800 mA
From 7 V 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
E5V CN7 pin 6
4.75 V to 
5.25 V
500 mA -
Table 8. Power-related jumper 
Jumper Description
JP5
U5V (ST-LINK VBUS) is used as a power source when JP5 is set as shown below 
(Default setting)
VIN or E5V is used as a power source when JP5 is set as shown below.