I don't think the lens I gave you gives much useful information. Here is some short information.
When you photograph something you will get a signal. You will also get some noise. Most of the noise is coming from light itself. Light comes in quanta, called photons. A pixel captures photons and converts them to electrons. A fairly normal pixel may hold something like 50000 electrons. You need 16 bits to count 50000 electrons. But you also have noise. Major sources are shot noise which is natural variation of photons, this is proportional to the square root of the number of photons. So if you had say 64 photons falling on a 100 pixels, the signal from the pixels would vary between 56 and 72 (not exactly, somewhat simplified), that really means that the last few bits are pretty meaningless.
Another form of noise is readout noise, this can be very load on modern CMOS sensors (like +/- 3 electrons) but quite a bit higher (like +/- 15 electrons) on the CCDs typically used in MFD. The shot noise is normally quite smooth while readout noise is more ugly (pepper salt type).
So the readout channel on a MFDB may be 16 bit but of those 16 bits 4 bits will be noise. The information is actually around 12 bits.
If you transfer color, there are three channels. So, theoretically an MFDB would be able to separate between 2**(3*12), that is 68 billion (US) colours. the real number is much lower, a more typical value may be something like 25 bits, that still means 33 million different colors.
The MFDB sensors are larger, so they capture more photons. So the noise from sensor can be lower than on smaller sensors even if the noise/are is higher.
Thanks Erik I will look at it in depth after work.