Power Traces in Tutorials (SCA101)

I know already that the array representing the power measuremnts / traces plotted in the tutorials originate from the AC coupled measurement input(using a SMA cable ), filtered by the variable gain amplifier and the fed to the ADC 10-bit for instance in ChipWhisperer Lite capture board. But what about the units of y axis namely the units of the power traces that are captured (e.g. using the cw.get_last_trace() method ). Is there anywhere stated in the documentation if this power is measured in mW for instance or something?

Secondly, I would like to ask if the traces captured is by my chipwhisperer lite XMEGA is ok to to be somewhat different when compared to capture images provided? If you could check the attachment I provided you 'll understand what I mean by saying that they differ. To me it makes sense since I am able to proceed with the tutorials and for instance being able to distinguish the traces from correct and false input for the Lab2_B(SCA101)
My capture from XMEGA:

Solution capture provided for XMEGA:

P.S. I have to admit that I didn’t expect chipwhisperer project to be that too good. I am really impressed, my sincere applauds to everyone working and contributing to this amazing project!!

The Y axis of the power traces is proportional to the AC-coupled current consumption of the target device. It’s hard to be more specific than that - the shunt resistor used for measuring the current and the gain of the ChipWhisperer’s amplifier both vary.

Regarding your traces being different, that should be fine. I’d recommend plotting both the trace that’s different and another trace, instead of just the difference from the reference, just to make sure the trace looks valid.

Also, thank you for the compliment about the project :slight_smile:


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