STM32f4-discovery micro AB connector as power source

[giu]

Posted on February 22, 2012 at 13:38

is it possible to use the micro AB USB connector to power up the stm32f4-discovery board instead of the mini USB?

[raffael]

Posted on February 22, 2012 at 15:30

Hello

No, this is not possible without modifying the board. (I tested it.)

See page 34 of the STM32F4-Discovery user manual UM1472.

There are different possible solutions, but it depends on your application. (simultaneous debug with micro USB, other supply, ...)

I would suggest to solder a diode between VBUS (CN5) and 5V. (The equivalent of D1)

In order to prevent potential damage to the USB Power switch (U6) you should ensure that it's disabled. (See the link below, 3.4 Reversed current blocking.)

To do this it should be sufficient to desolder R46. (Eventually connect _EN to VBUS)

This solution should be safe to use even with the two USBs connected.

http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00167470.pdf

[giu]

Posted on February 23, 2012 at 13:00

Thank you very much for answering,

I assume that the micro-AB GND is already connected to the board GND pin.