Analog Devices VCA ???

[Haible_Juergen#Tel2743]

> The clock rate should be at least twice the frequency of the highest
> expected harmonic.  Alias artifacts could be a problem.

Why should anybody want to build PWM "VCA"s nowadays ??
This will only cause you trouble. Go figure what pulse/period
percentage you'd need for, say, 80dB attenuation.
Compare this with the offset drift of some opamp you'd use to
control it.
And if you should, for some reason, have to connect two
modules with PWM technique, which don't run from the same
clock, now *that's* where aliasing problems really start!

JH.