Power Supply And Power Selection; External Power Supply Input; Table 7. Power Source Capabilities - ST STM32U083C-DK User Manual

6.4

Power supply and power selection

6.4.1

External power supply input

Several DC power sources can power the STM32U083C-DK Discovery kit. It is possible to supply the
STM32U083C-DK Discovery kit with any of the following sources:
• 5V_STLK: 5 V from the STLINK-V2EC USB Type-C
• 5V_VIN: 7 to 12 V from the ARDUINO
• E5V: External 5 V power from extension connectors
• VBUS_STLK: 5 V from the user USB Type-C
• 5V_USB: 5 V from the USB Type-C
Note: If the 5V_VIN or E5V DC power source is used to power a board, this power must comply with the EN-62368-1:
2014/A11:2017 standard and must be safety extralow voltage (SELV) with limited power capability.
The power supply capabilities are shown in
Input power
5V_STLK
VIN
E5V
VBUS_STLK
5V_USB
5V_STLK is a 5 V DC power with limitations from the STLINK-V2EC USB connector (CN1). In this case, the 5V
jumper selection (JP3) must be on [1-2] to select the STLK power source on the JP3 connector. This is the default
setting. If the USB enumeration succeeds, the STLK power is enabled, by asserting the T_PWR_EN signal
coming from STLINK-V2EC. This pin is connected to a power switch, which powers the board. This power switch
also features a current limitation to protect the PC in case of a short circuit on board, detected with a current
higher than 750 mA.
The STM32U083C-DK Discovery kit and its shield can be powered from the STLINK-V2EC USB connector
(CN1), but only the STLINK-V2EC circuit is powered before USB enumeration because the host PC only provides
100 mA to the board at that time. During the USB enumeration, the STM32U083C-DK Discovery kit and its shield
request no more than 500 mA current.
• If the host can provide the required power, the enumeration ends with a SetConfiguration command. Then,
the power transistor is switched ON and the green LED (LD3) is turned ON. Thus, the STM32U083C-DK
Discovery kit and its shield request no more than 500 mA current.
• If the host is not able to provide the required current, the enumeration fails. Therefore, the power switch
stays OFF and the MCU part including the expansion board is not powered. As a consequence, the green
LED (LD3) stays turned OFF. In this case, it is mandatory to use an external power supply.
UM3292 - Rev 1
®
or extension connectors, with 5 V adaptation from LDO
®
connector
Table
Table 7.
Connector
Voltage range
pins
CN1 JP3[1-2] 4.75 to 5.5 V
CN6 pin 8
7 to 12 V
JP3[7-8]
CN7 pin 6
4.75 to 5.5 V
JP3[3-4]
CN1
4.75 to 5.5 V
JP3[9-10]
CN14
4.75 to 5.5 V
JP3[5-6]
®
connector
®
connector without enumeration
7.
Power source capabilities
Maximum
current
The maximum current depends on the USB
enumeration:
500 mA
• 100 mA without enumeration
• 500 mA with good enumeration
From 7 to 12 V only and the input current capability
is linked to the input voltage:
800 mA
• 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
The maximum current depends on the power source.
1 A
1 A maximum is recommended for this board.
The maximum current depends on the USB Host
500 mA
used to power the board. No USB enumeration.
The maximum current depends on the presence or
500 mA
absence of the USB enumeration.
UM3292
Hardware layout and configuration
Limitation
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