Brian Clewer wrote:
> If you draw a straight line graph, the formula is Y=MX+C where M is
> the gradient and C is the offset.  What you are asking for (I think)
> is to get a 14 bit number out of a voltage from 0-5V.  This could be
> done with some very careful opamp signal conditioning.  You need to
> raise the gradient of the line, but at +5v input, this would give you
> too many volts at your A-D.... Ok, so you could have a comparator
> checking the voltage at the A-D and when it reaches +5v, it could put
> an offset back into the amp section bringing it back to 0v.  With
> that same comparator, you could then tell the PIC there is another
> MSB to add.  You could then calibrate the device to compensate for
> ant offset.

That may sound good in theory, but in practise it will be very difficult to
match up the multiple ranges correctly to the implied output accuracy.


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