8 Feb
2022
8 Feb
'22
11:49 a.m.
On Feb 8, 2022, at 2:34 PM, Douglas Taylor via cctalk
<cctalk at classiccmp.org> wrote:
Update on this: I did put together a battery and voltage divider to test the AXV11. The
label on the A/D module says it brings the output from the multiplexer to one of the
external pins. I was able to verify that the voltage applied to a couple of the A/D
inputs makes it through the multiplexer when selected using the CSR. The next output
available is from the Sample and Hold, and this is always pegged at +12v. Am I wrong to
assume that the sample and hold will 'freeze' its output when the A/D go bit is
set?
You're correct, a S/H circuit is supposed to hold the value that was on its input at
the time it was told to take the sample. Typically it won't hold it
"forever"; S/H circuits have a hold time spec chosen so it is substantially
longer than the time it takes the A/D behind it to complete its measurement.
paul