[sdiy] small ,higher than 8 input multiplexers?

[David G. Dixon]

> Sorry Dave, but I'm with Ingo. You don't need the 2-to-1 multiplexer
> afterwards. you can just use multiple 4051s and only enable one of 'em.
> 
> I've done this multiplexing CVs from a control panel into an ADC. The
> panel is broken up into groups of eight, each of which has a 4051.
> The master uP can select which control board it is reading, and which
> pot on that board just by doing a bit of address decoding. I designed
> for up to 64 pots like this, but haven't (quite) used them all.

Yes, this is an excellent idea.  The only caveat I would have is that the
pinout of the 4051 is really goofy (the channels are out of order, the O/I
pin is right in the middle of the channel pins on one side, etc) whereas the
4067 has 8 channels either side arranged in order in unbroken lines.  Hence,
given the challenges of laying out 4051, by the time everything is routed
correctly, the 4067 might not actually take up that much more board space,
particularly if the address lines must be shared between several chips.