[sdiy] Exar XR-2206/2207s bite the dust

[Tim Parkhurst]

On Sat, Apr 2, 2011 at 2:43 PM, The Old Crow <oldcrow at oldcrows.net> wrote
>  I used the 4151 in the VCO I designed to operate like a Yamaha IG0053
> (VCO-III) chip.  JRC also makes the 4151, so hopefully it will be around for
> a while.  The Chroma VCOs used them.  --Crow
>

Okay, so looking at the data sheet, it looks like Fig. 3 is using the
same trick that TH uses to improve the linearity of many linear VCO
chips - put an op amp in a feedback loop for the CV input. Hang a CV
summer / expo converter on the front end, tap a triangle off the
timing cap with another op amp and you're ready to run.

Gonna have to buy a few and play around. :)


Tim (watching The Lost Boys and playing with an SEM - what a great day!) Servo
-- 
"Sire, the church of God is an anvil that has worn out many hammers."
- H.L. Hastings