Hardware and layout
STM32F4DISCOVERY
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Doc ID 022256 Rev 2
4.3
Power supply and power selection
The power supply is provided either by the host PC through the USB cable, or by an external
5V power supply.
The D1 and D2 diodes protect the 5V and 3V pins from external power supplies:
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5V and 3V can be used as output power supplies when another application board is
connected to pins P1 and P2.
In this case, the 5V and 3V pins deliver a 5V or 3V power supply and power
consumption must be lower than 100 mA.
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5V can also be used as input power supplies e.g. when the USB connector is not
connected to the PC.
In this case, the STM32F4DISCOVERY board must be powered by a power supply unit
or by auxiliary equipment complying with standard EN-60950-1: 2006+A11/2009, and
must be Safety Extra Low Voltage (SELV) with limited power capability.
4.4
LEDs
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LD1 COM: LD1 default status is red. LD1 turns to green to indicate that
communications are in progress between the PC and the ST-LINK/V2.
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LD2 PWR: red LED indicates that the board is powered.
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User LD3: orange LED is a user LED connected to the I/O PD13 of the
STM32F407VGT6.
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User LD4: green LED is a user LED connected to the I/O PD12 of the
STM32F407VGT6.
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User LD5: red LED is a user LED connected to the I/O PD14 of the STM32F407VGT6.
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User LD6: blue LED is a user LED connected to the I/O PD15 of the STM32F407VGT6.
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USB LD7: green LED indicates when VBUS is present on CN5 and is connected to PA9
of the STM32F407VGT6.
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USB LD8: red LED indicates an overcurrent from VBUS of CN5 and is connected to the
I/O PD5 of the STM32F407VGT6.
4.5
Pushbuttons
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B1 USER: User and Wake-Up button connected to the I/O PA0 of the
STM32F407VGT6.
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B2 RESET: Pushbutton connected to NRST is used to RESET the STM32F407VGT6.