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paul19
Associate III
May 28, 2021
Solved

How much current can I draw from the NUCLEO-64's pins?

  • May 28, 2021
  • 2 replies
  • 3098 views

What's the maximum amount of current which I can draw from a NUCLEO-L476RG output pin? (in order to power a light source) Is there a limit per pin as well as an overall limit for the whole board?

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Best answer by Peter BENSCH

It depends on the target device, which is mounted to the NUCLEO-64.

Just to take the example of a NUCLEO-G071RB, where the target MCU is the STM32G071RB, you will find these currents in the datasheet of that target device. Please keep in mind that Absolute Maximum Ratings is not identical to usual working conditions!

You will find the working conditions in section 5.3.14, I/O port characteristics and the output driving current with up to ±6mA, and up to ±15mA with relaxed VOL/VOH.

Of course the sum of all currents from all GPIOs at the same time is limited, in this case to 80mA, as mentioned in table 19.

BTW: you can increase the current per "channel" if you connect GPIOs together and drive them with exactly the same pattern, which means you may not need an external transistor/driver.

Good luck!

If the problem is resolved, please mark this topic as answered by selecting Select as best. This will help other users find that answer faster.

/Peter

2 replies

Peter BENSCH
Peter BENSCHBest answer
ST Technical Moderator
May 28, 2021

It depends on the target device, which is mounted to the NUCLEO-64.

Just to take the example of a NUCLEO-G071RB, where the target MCU is the STM32G071RB, you will find these currents in the datasheet of that target device. Please keep in mind that Absolute Maximum Ratings is not identical to usual working conditions!

You will find the working conditions in section 5.3.14, I/O port characteristics and the output driving current with up to ±6mA, and up to ±15mA with relaxed VOL/VOH.

Of course the sum of all currents from all GPIOs at the same time is limited, in this case to 80mA, as mentioned in table 19.

BTW: you can increase the current per "channel" if you connect GPIOs together and drive them with exactly the same pattern, which means you may not need an external transistor/driver.

Good luck!

If the problem is resolved, please mark this topic as answered by selecting Select as best. This will help other users find that answer faster.

/Peter

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.
paul19
paul19Author
Associate III
June 2, 2021

Great, thanks.