Sawtooth generator with single op-amp 1

[okivrak]

Hi everybody

Is it possible to obtain sawtooth signal output from a single op-amp with DC input voltage?
I know that it's possible with 2 op-amps but my aim is to use just one.

Could you recommend any circuit schematic or website?

Thanks a lot.

 

[roydm]

Check out the following

http://www.mitedu.freeserve.co.uk/Circuits/cctindex.html

Roy

 

[GonzaloEE]

Maybe an oscillator with a coil at the output to make sloped pulses.

 

[VEBill]

A 555 timer has a pretty good ramp waveform on the timing capacitor (it is reasonably linear since the RC is restricted to just one-third of the rail).

 

[Comcokid]

A crude method of doing a sawtooth with a single op-amp is to make a square-wave oscillator, run that through a high-value resistor, and into a capacitor. With a high-value resistor, it begins approaching a square-wave driven constant-current source into a capacitor. The R/C is not apparent on a scope.

Now, vary the duty-cycle of the oscillator, and you can make it approach a sawtooth.

 

[fsmyth]

Just stumbled across a novel sawtooth generator, and
reposted it at:

http://hmin.tripod.com/als/fsmyth/pages/video-6.html#VID45

There is another here:

http://hmin.tripod.com/als/fsmyth/pages/timers3.html

I know I have some more, but have not had a chance to
add them to the site.
<als>

 

[bhuvan]

I've used this circuit for years using a single comparator to generate triangle waves. By adjusting resistors R1, R6, R5 & R10, a sawtooth can easily be synthesized.



Bhuvan