Harold Hallikainen <haroldhallikainen@JUNO.COM> wrote:
<snip>
 <<       Summarizing...  If all you need is 8 bits of A/D, why not use a
chip with it on it?  It then takes NO external parts and works well.  If
more resolution is used, there are several single chip solutions that
don't require you to put a bunch of op amps and switches together.  Why
not take advantage of the expertise that went into the design of the A/D
chips that are out there?>>

Excellent technical points in the clipped part of this post.  However,  cost
raises its head in production.  When I build something with a $10 BOM, I am
not going to throw away $1.25 (difference in cost -- production quantities --
between 'c54 and 'c71) in recurring cost, when I can put in a $.05 cap and
sweat a bit over calibration issues -- once -- unless there is a very good
reason to do so.

Mike Mullen