I've run the numbers for FWC's of 100,000, 60,000, 40,000, and 25,000
they all come out the same
I don't know the amount of current running through any sensor though
if we knew how many amps for a given sensor, we could compute power gain
and since that is 10 log, it probably is 3dB per stop
the problem with Canon sensors is that damnable bias offset
at lower ISO settings, the bias offset allows read noise to intrude into signal
because of how DXO computes S/N
the ratio between maximum signal and the average of read noise
Canon sensor DR flattens out at low ISO
usually, the first two or three ISO settings have exactly the same dynamic range
the next stop tends to have slightly less, but usually not a full stop less
from that point on dynamic range drops off as a linear function
Canon's problem is how they deal with read noise...which these days, is quite ineffectively.
Their CDS design is ancient, and clearly not up to the task.
Canon has been on a 500nm process for over a decade, where as most other sensor manufacturers started moving to the 180nm process several years ago.
Canon seems to have a 180nm process of their own, they used it in both the 50mp and 120mp APS-H sensors. They also have lightpipe technology on a 180nm Cu process.
They don't seem to have ramped up any kind of FF or APS-C fabrication capacity on that process yet, for whatever reason.