I came across the attached schematic sometime back, and saved it for future reference. Well, the future is now, and I uploaded to a Multisim program which shows the output as sawtooth, but with unstable levels, and a freq of 38KHz (multisim jpeg attached). I built the circuit on a breadboard, and the output appears to be a nice sawtooth, with the frequency around 20KHz (screenshot jpeg attached). The 50pF capacitor appears to control the output frequency, up to a point. Above 35KHz there is significant clipping.
Question:
Can someone explain what's going on? Is there a name for this circuit? I understand the feedback path between pins 7 & 1 and pin 3, but what's with the two diodes? And is there a way to get the frequency up around 50KHz (which is what I need) without the distortion and clipping? (ie- faster response diodes, or different op amps, or something else).
As always- thank you to all the knowledgeable experts out there!
Question:
Can someone explain what's going on? Is there a name for this circuit? I understand the feedback path between pins 7 & 1 and pin 3, but what's with the two diodes? And is there a way to get the frequency up around 50KHz (which is what I need) without the distortion and clipping? (ie- faster response diodes, or different op amps, or something else).
As always- thank you to all the knowledgeable experts out there!
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