Originally Posted by dingenus
Andy, as far as I know is a Sensor an analoge divice. There is no D-A--A-D conversion, only A-D.
But you can made that in different ways. You can amplify the analoge signals before conversion or after that.
I think that this is the difference between the G1 and the GH1.
If you do analoge amplifying etcetera before conversion, that would adding noise and, maybe, interfere between channels.
If you do the conversion (nearly) on chip and the amplifying after conversion, and do that well, there would be a cleaner signal.
Both ways are usable and there are naturally more possible variationen.
CCD sensors are analogue, internally, CMOS sensors often have the A-D 'on chip'. I think you are right - Canon CMOS sensors appear to have the ADC on-chip, whereas most of the LiveMOS sensors would appear to have this on the processor (Truepic or Venus). The exception would appear to be the GH1 chip, where the ADC is on chip and hence the output is digital.
I have not seen a LiveMOS chip architecture block diagram, but it would be interesting if you know of where one is.