Generating a Backwards Sawtooth Waveform: Is an Op-Amp Circuit the Solution?

[Jdo300]

Hello All,

Does anyone know of a simple circuit (with op-amps or something) that can generate a backwards sawtooth waveform? In otherwords, the waveform would have a sharp rise time and then slop off linearly. (see attachment).

Thanks,
Jason O

 

[berkeman]

Maybe generate a traditional sawtooth (integrate and dump), then invert it and offset it? Would that work?

 

[Jdo300]

Hi Berkeman,

Ok, here's what I came up with. Looks like it is working . Does anyone know of any other ways to do this that may be simpler?

Thanks,
Jason O

 

[berkeman]

Simpler... How about a single 8-bit downcounter with an R-2R ladder DAC configuration at the output...

 

[Jdo300]

Hmmmm... that could work :-). I wonder what kind of frequency range I can get from that. I would definitely need to buffer the output. Interesting approach.

Thanks,
Jason O