[sdiy] Sine to Tri

[John Mahoney]

At 06:34 PM 3/30/2006, Tim Parkhurst wrote:
>Okay, here's one I haven't seen before... I'm looking for a circuit to
>convert a sine wave into a triangle. Is there a function / circuit
>that would do this? Am I looking for an antilog amp?
>
>Tim (where the deer and the antilog play) Servo

You're a madman! ;-) Who would want to do such a thing?

Well, this might work:
-- sine to square
-- square through a slew limiter becomes a triangle (must it be a 
bipolar square?)
-- amplitude compensation device (ACD)

The triangle's amplitude will vary inversely to the frequency. The 
ACD has to counteract this. So...

If a pitch CV is available, use it to control a (linear?) VCA. 
There's your ACD.

If there's no pitch CV, a frequency-to-voltage convertor is needed. 
Add a VCA, as above.

You didn't say this had to be simple or cheap! :-)
--
john