CWNano Power Captures

[Riddhi]

1. When I plot the “power consumption” curve in CWNANO, is it plotting the product of the instantaneous current through and voltage across the shunt resistor in the board?
2. Let’s say I want to capture the power consumption from two operations x=12+34 as opposed to power consumption from x=34+45. Note that the numerical quantities are different but the operations remain the same. Will the power consumption curves be different?

[Alex_Dewar]

@Riddhi

When I plot the “power consumption” curve in CWNANO, is it plotting the product of the instantaneous current through and voltage across the shunt resistor in the board?

No, it’s plotting the AC coupled voltage across the shunt resistor, which is proportional to current.

@Riddhi

Let’s say I want to capture the power consumption from two operations x=1*2+3*4 as opposed to power consumption from x=3*4+4*5. Note that the numerical quantities are different but the operations remain the same. Will the power consumption curves be different?

The part that’s going to show up most strongly is probably the Hamming weight of the SRAM write of the final result, if it does one. The curves will be different, but that’ll mostly be due to noise. You might be able to see a difference if you average a bunch of traces of both and take the difference.

[Riddhi]

I see. Thank you so much for the clarification. That makes sense.