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MMala.3
Associate II
March 28, 2024
Solved

STM32G4 comparator source sink current

  • March 28, 2024
  • 3 replies
  • 1409 views

Hi

Is there any info available regarding source sink current of analog comparators on the STM32G4 series.

The datasheet doesn't contain any info on this although the drive current of Opamps is mentioned as 500uA.

TIA

Best answer by Peter BENSCH

Now, after a look at RM0440, section 24.3.1, you will realise that the (digital) output of the comparators is not routed directly to the pins, but via a (digital) polarity switch. Only then is the signal available at the GPIO, which results in the current carrying capacity of a GPIO.

[edit] I forgot to point out that the respective COMPx_OUT is an Alternate function output, which is visible in fig. 25 as input of the digital GPIO driver. [/edit]

Does it answer your question?

Regards
/Peter

3 replies

Peter BENSCH
Peter BENSCHBest answer
Technical Moderator
March 28, 2024

Now, after a look at RM0440, section 24.3.1, you will realise that the (digital) output of the comparators is not routed directly to the pins, but via a (digital) polarity switch. Only then is the signal available at the GPIO, which results in the current carrying capacity of a GPIO.

[edit] I forgot to point out that the respective COMPx_OUT is an Alternate function output, which is visible in fig. 25 as input of the digital GPIO driver. [/edit]

Does it answer your question?

Regards
/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.
MMala.3
MMala.3Author
Associate II
March 28, 2024

Hi

Is it correct to say that the comparator output source sink current spec is same as the GPIO source sink capability.

The GPIOs (general purpose input/outputs) can sink or source up to ±8 mA, and sink or
source up to ± 20 mA (with a relaxed VOL/VOH).

This is stated in the STM32g491 datasheet Pg114.

TIA

 

 

Peter BENSCH
Technical Moderator
March 28, 2024

Yes.

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.