ST NUCLEO-H745ZI-Q, Руководство пользователя

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UM2408 Rev 1 27/45
UM2408 Hardware layout and configuration
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LD6 USB power fault : LD5 indicates that the board power consumption on USB exceeds
500 mA, consequently the user must power the board using an external power supply.
LD7 and LD8 USB FS: refer to Section 6.11: USB OTG FS or device .
6.7 Push-buttons
B1 USER (blue button): the user button is connected to the I/O PC13 by default (Tamper
support, SB82 ON and SB81 OFF) or PA0 (Wakeup support, SB81 ON and SB82 OFF) of
the STM32H7 microcontroller.
B2 RESET (black button): this push-button is connected to NRST and is used to RESET
the STM32H7 microcontroller.
6.8 JP4 (IDD)
Jumper JP4, labeled IDD, is used to measure the STM32H7 microcontroller consumption by
removing the jumper and by connecting an ammeter:
•
JP4 ON: STM32H7 is powered (default) o JP4 OFF: an ammeter must be connected to
measure the STM32H7 current. If there is no ammeter, the STM32H7 is not powered
Warning: On MB1363 REV.C, "VDD_MCU" is also supplying Ethernet
PHY (U15) and debug voltage translation (U1 & U10).
If needed, for low power measurement (for example standby mode), in order to measure
only MCU (U7) power consumption, the user must remove the following components: R4,
R43, R44, R45, R46, R47, R48, R49, R50, R51, R52, R53, R59, R64, U1, U10, U15 &
SB72.
After removing these components, it will become impossible to use Ethernet, and 1.8 V
debug with ST-LINK.
6.9 OSC clock
6.9.1 OSC clock supply
There are four ways to configure the pins corresponding to the external high-speed clock
(HSE):
• MCO from ST-LINK (default): MCO output of ST-LINK is used as input clock. This
frequency cannot be changed, it is fixed at 8 MHz and connected to the PH0-OSC_IN
of STM32H7 microcontroller. The configuration must be:
–
SB71 OFF
– SB72 ON
– SB3 and SB4 OFF
• HSE on-board oscillator from X2 crystal: for typical frequencies and its capacitors and
resistors, refer to the STM32H7 microcontroller data sheet and to the
Oscillator design
guide for STM8S, STM8A and STM32 microcontrollers Application note (AN2867) for