MUX

[Mikko Helin]

On Fri, 3 Dec 1999, Guido Goebertus wrote:

> 
> Can I use standard CMOS 4051/4067 for the MUX? Or is it better to use
> HCT series? What would be a good choice for the hold caps (type,value)?

Use the CMOS muxes as you can use them with >5 V voltages, and
the max. CV out is about 10 V - Vref for 127 MIDI notes in 1/2 steps
is 127/12 = 10.583333... V, so 12V is a good Vcc for the mux.

Use 0.1 uF caps with TL082 or TL084 op amps. I think polyester
caps are OK in S/H's, though there might be better ones, but
ceramic caps are not recommended (though I don't know why).

I think at PAiA site (www.paia.com) has schematics of the
MIDI2VC8 converter, see how the S/H's are done there.

-Mikko

> 
> Guido
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