Skip to main content
SRivi.1
Associate II
Dec 8, 2020 2:51 PM UTC
Solved

Output Pin

Hi, I have a Nucleo 144 - STM32H743ZI2 and I need that the output pins deliver 5V, no 3.3V. Is it possible?

Thanks

This topic has been closed for replies.
DJC
DJCBest answer
Senior
Dec 8, 2020 3:00 PM UTC

The short answer is "no" right out of the box.

However, you are trying to send 5V signals (not power) to a device, you can look for a 5V tolerant pin (often marked as FT) and then use an open-drain configuration with no internal pull up or pull down. Then select an extrarenal pull up resistor that fits well inside the current rating. You need to check the electrical characteristics to see what kind of 5V currents it can sink. (typically just start with 100k... but check the docs).

The result is that the resistor provides your 5V signal as default and your chip provides the ground.

Would be really happy to hear if someone disagrees with me on this one... I plan to put this into production.

3 replies

DJC
DJCBest answer
Senior
Dec 8, 2020 3:00 PM UTC

The short answer is "no" right out of the box.

However, you are trying to send 5V signals (not power) to a device, you can look for a 5V tolerant pin (often marked as FT) and then use an open-drain configuration with no internal pull up or pull down. Then select an extrarenal pull up resistor that fits well inside the current rating. You need to check the electrical characteristics to see what kind of 5V currents it can sink. (typically just start with 100k... but check the docs).

The result is that the resistor provides your 5V signal as default and your chip provides the ground.

Would be really happy to hear if someone disagrees with me on this one... I plan to put this into production.

DJC
Senior
Dec 8, 2020 3:01 PM UTC

p.s. if you want to send power. ST has loads of power management devices that can be controller by the mcu.