ADC just giving raw value of 4095 on all channels

[harshpanchal_6]

Hello Community,

I’m working on a custom board using the STM32G474VET3 MCU and encountering an issue with the ADC readings. I’m consistently getting a raw value of 4095 on all the ADC channels I’m using. It seems like something might be misconfigured, but I haven’t been able to pinpoint the cause.

Any insights or suggestions would be greatly appreciated.

Thank you!

[TDK]

Sounds like VREF+ might not be connected. 18 replies in this thread and still no schematic that includes this pin.

[harshpanchal_6]

I am providing +3V3DC to analog pin for Vref based on datasheet its and output pin.  

[harshpanchal_6]

I am providing +3V3DC to analog pin for Vref based on datasheet its and output pin.  

[Hl_st · Accepted solution]

I think if you update this circuit by connection VREF+ also to 3V3 as VDDA, ADC will work correctly.   

[TDK]

VREF+ needs to be powered. Connect it to VDDA.

[Andrew Neil]

@harshpanchal_6  Note that everyone can see all replies - there's no need to repeat the same thing in reply to different people.

You can use '@' to mention people ...

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@harshpanchal_6 wrote:

I am providing +3V3DC to analog pin for Vref based   

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No, your schematic shows that you are not providing any supply at all to Vref.

This is why it is so important that you show your full schematic in your first post.

It shouldn't have taken 20  posts to get here!

Thank you for marking the solution - don't forget to also do that in your previous posts...