MP2, ADC and noise

[tarzan2]

Hello,

I plan to use a MP2 on a SOM module (probably something like the KaRo QFN-like QSMP2 module).

This MP will run a linux on the A35 core and real-time software on the M33, + USB2, ETH 100 Mbps.

I need 11 ADC channels to convert analog signals at 500kSPS. There is enough ADC input to do that at the required sample rate but what about noise ?

The datasheet claims ~9.3bits of ENOB, this the enough BUT I suppose that obviously, this is in the best case.

Activating LPDDR4 + USB2 + ETH will generate a lot of board noise and will probably degrade the ADC ENOB. But how much ?

Does anyone experienced some noise measurement on MP1/MP2 device with DDR and hi-speed IF activated ?

Thanks for the feedback !

[Maxime_MARCHETTO]

Hello @tarzan2,

This post has been escalated to the ST Online Support Team for additional assistance.  We'll contact you directly.

Best regards,
Maxime

[Olivier GALLIEN]

Topic answered in OLS case : 

For reference :

Unfortunately, we cannot tell what to predict really. You have to test on Evaluation board to see the impacts. At least the ADC IO ball should be far from USB or ETH balls - see guideline in AN2834 - also activate the oversampling if possible.

Olivier