[sdiy] Idea - Triangle wave DCO core

[David G Dixon]

> You'd need some sort of servo mechanism around the integrator 
> to deal with any DC drift, otherwise you'll end up hitting 
> one of the rails sooner or later as DC terms get integrated over time.

I concur.  I don't see any way around the schmitt trigger.  However, it
could simply fire an electronic switch between the CV inverter + input and
ground to change the polarity of the CV into the integrator.  Essentially,
then, you'd have a digital expo, so you'd need some pretty high resolution
for tuning.  Expo FM would simply be counting in binary up and down.  Could
be kewl.