Dropouts in ADC capture on STM32H743

[ANovi.7]

If I connect a constant rising signal at the ADC input, I observe significant fluctuations at certain ADC values. These fluctuations always appear at the same ADC values. The affected values have the following format XX500, e.g. 18500, 19500, 20500 etc.

I was also able to reproduce this behavior with the NUCLEO-H743ZI and the example projects (ADC_DMA_Transfer and ADC_RegularConversion_Polling) from the current cube firmware V1.5.0. The graphic in the appendix shows a recorded ADC values, which shows the problem.

Can someone help me to solve the problem?

[Mikhail Z]

Did you try to disconnect the Ethernet PHY?

https://community.st.com/s/question/0D70X000007PAk8/fluctuations-in-adc-value-of-stm32h743-mcu?s1oid=00Db0000000YtG6&t=1572098945317&s1nid=0DB0X000000DYbd&emkind=chatterCommentNotification&s1uid=0050X000007vuOa&emtm=1571808056457&fromEmail=1&s1ext=0

[ANovi.7]

This issue concerns more the noise or the behavior in the static state. I got that with the hardware and software filter in the handle. In my case, the dropouts with a constantly rising signal are the problem. These dropouts still occur at the same ADC values. That's why it can not be due to the Ethernet PHY.

[PWalt.2]

I am using an H750RevV with HalV1.9. I am seeing these issues on both ADC1 and ADC3. It is definitely related to a calibration issue, but that is not the only factor. Depending on which microcontroller we are testing, we will see anywhere from 0 gapping to ~150 ADC count gaps (this is 16 bit ADC). We were able to replicate this on evaluation kits as well. There are regions in the digital output that are just jumped over (ie offset).

We switched from ADC_CALIB_OFFSET to ADC_CALIB_OFFSET_LINEARITY which solved the problem on most devices but not all.

We are still seeing this issue, is there anyone who has absolutely eradicated this?