ST NUCLEO-H7S3L8 - Power supply and power selection

6.4 Power supply and power selection
6.4.1 External power supply input
Several DC power supplies can power the Nucleo board. It is possible to configure the Nucleo board to use any of
the following sources for the power supply:
• 5V_STLK from STLINK-V3EC USB Type-C
®
connector (CN5)
• VIN (7 to 12 V) from ARDUINO
®
‑included Zio connector (CN8) or ST morpho connector (CN11)
• 5V_EXT from ST morpho connector (CN11)
• 5V_UCPD from USB Type-C
®
connector (CN2)
If VIN or 5V_EXT are used to power the STM32H7Rx/7Sx Nucleo-144 board, these power sources must comply
with the standard EN‑60950‑1: 2006+A11/2009 and must be safety extralow voltage (SELV) with limited power
capability.
The power supply capabilities are summarized in Table 8.
Table 8. Power source capabilities
Input
power
name
Connector pins
Voltage
range
Maximum current Limitation
5V_STLK
CN5
JP3 [1-2]
4.75 to 5.25
V
500 mA/1.5 A/3 A ST-LINK manages the maximum current.
VIN(5VIN)
CN8 pin 15
CN11 pin 24
JP3 [3-4]
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
5V_EXT
CN11 pin 6
JP3 [5-6]
4.75 to 5.25
V
500 mA The maximum current depends on the power source.
5V_UCPD
CN2
JP3 [7-8]
4.75 to
5.25 V
Up to 1.5 A
The maximum current depends on the USB host used
to power the Nucleo when the user USB connector
(CN2) is used as a sink port
5V_STLK
5V_STLK is a DC power with the limitation of the STLINK-V3EC USB Type-C
®
connector (CN5). In this case, the
JP3 jumper must be on pin [1-2] to select the 5V_STLK power source.
This is the default setting. If the USB enumeration succeeds, the 5V_STLK power is enabled, by asserting the
T_PWR_EN signal from
STLINK-V3EC MCU (U14). This pin is connected to the U10 power eFuse, which powers
the board. This power eFuse also features a fast overvoltage current limitation, to protect the PC in case of an
onboard short-circuit. The STLINK-V3EC MCU (U14) determines the maximum current.
The NUCLEO-H7S3L8 Nucleo board with its shield can be powered from the STLINK-V3EC USB connector
(CN5), but only the STLINK-V3EC circuit has the power before USB enumeration because the host PC only
provides 100 mA to the board at that time. During the USB enumeration, the Nucleo board requires a 500 mA or
more current from the USB host.
If the host can provide the required power, the enumeration finishes with a SetConfiguration command. Then, the
power eFuse (U10) is switched ON, the green LED (LD5) is turned ON, thus the Nucleo board with its shield can
consume 500 mA or more current determined by ST-LINK.
UM3276
Hardware layout and configuration
UM3276 - Rev 1
page 14/40