CW305 Artxi FPGA - Product Selection

Embedded Security ChipWhisperer Hardware
1

I am planning to purchase the CW305 Artix FPGA Board in order to attack the AES with proposed method as demonstrated in the GitHub repository of yours. At the first place I was thinking to perform power measurements (SCA) utilizing the ChipWhisperer Lite and then also using a typical/conventional oscilloscope. I believe that both 7A35 and 7A100 FPGA parts perform decent for the suggest ECC implementation. So I was wondering if the selection of the shunt and capacitor is going to have such a big impact on my measurements? In other words, are my measurements going to be that noisy due to the resistor selection? I would be truly grateful if you could give some piece of advice.

Thank you in advance.

2

Hi,

If you intend to perform side-channel power measurements via the shunt resistor (i.e. not with an EM probe), then you need a shunt resistor mounted, and no VCC-INT decoupling capacitors.

For both our AES and ECC example bitfiles, the 0.5 ohm shunt option is what I have and it works well.
For reference, the ECC bitfile utlizes approximately 20% of the 7A100’s resources, and Vivado estimates its current draw at 0.16A. If you have other specific targets in mind, you could look at their estimated power draw to see where you stand.

Jean-Pierre