There are no instructions for calibrating ADC in STM32F407

[Patrick Morwald]

Posted on March 19, 2018 at 16:15

Hi, 

after googling around a while and reading the STM32 manual section for the ADC, i am frustrated about the lack of such a section in the manual.

So how IS the ADC in the STM32F4 actually calibrated??

EDIT:

I found this thread: 

https://community.st.com/0D50X00009XkYIWSA3

 

However, if i do so on my STM32F407VGT (Discovery Board), i dont have a VREFINT_CAL value.

Should i just measure VREFINT on Channel 17 of the ADC and assume this is exactly 1.25 V?

Thanks,

Patrick

#stm32f4 #adc #adc-calibration

[AvaTar]

Posted on March 19, 2018 at 16:40

I might want to check the RM, but I faintly remember the ADC does the calibration automatically.

Or the ADC code in the SPL said so ...

[Patrick Morwald]

Posted on March 19, 2018 at 16:47

Well, that would be OK for me if thats reliable. At least there are no library functions for calibration in my SDK...

[STOne-32]

Posted on March 19, 2018 at 17:45

Dear @Patrick

There is no hardware ADC calibration for our STM32F4, it is self-calibrated upon reset and once ADC is activated, However, I do not recommend to varies VDDA/ VREF+  voltage once ADC is activated, you should always keep them stable when it is active, else re-enable it again.  

For other STM32F1 as example, the calibration is able to compensate the Offset and you can do it from time to time when temperature change or VREF+  voltage Change.

Cheers,

STOne-32