Discrete triangle generator

[sovadk]

Hi

I've made a simple discrete triangle generator if any of you are interested.

With the current values it's osscilating at 1kHz. Decresing C2 will increese the frequency.

The schematic:

An externally hosted image should be here but it was not working when we last tested it.

A simulaion:

An externally hosted image should be here but it was not working when we last tested it.

I've attached the Orcad 10.3 project files.
Enjoy


Best regards
Kaspar Sinding Meyer

 

[Pierre]

Interesting...
Have you tried to put it to oscillate at about 250-400KHz? How does the triangle look like?

Best regards,
Pierre

 

[sovadk]

Good question. I have tryed that, The triangle wave gets a little bit idstorted in the bottom @ 400kHz, but else it looks fine. However I think that can be solved.

 

[sovadk]

Okey heres what you'll have to do to make it work @ 500kHz . Change R7 to 1.5k, R2 to 2.2k and C2 to 330p. To improve linearity decreese C7 to 47p.

This is my simulation results:

An externally hosted image should be here but it was not working when we last tested it.

One way to evaluate the linearity of the triangle wave is to look at it's derivative. One should expect a pure square wave. This is my results:

An externally hosted image should be here but it was not working when we last tested it.

 

[Pierre]

I must admit that's very good.
Have you used it in a Class-D amplifier?

 

[sovadk]

No I haven't yet used it, since I designed it yesterday.
Right now I'm using a solution with one comperator and a couple of BJTs. I've posted the design here:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=54263