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I'm currently trying to figure out how to design a free running ramp generator for a project. I'm required to use op amps for both the bootstrap sawtooth generator and the Schmitt trigger, and the required output voltage ranges from -8 to -1 V. This implies that the UTP is -1 and the LTP is -8.

I'm having a hard time understanding how the output of the bootstrap would be negative along with designing the Schmitt trigger such that both threshold voltages are also negative. Any tips? I've attached a picture of the reference circuit that they've provided, which is the only reference material provided to us.

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    \$\begingroup\$ Have you considered using a simulator and seeing how the circuit in your question performs? \$\endgroup\$
    – Andy aka
    May 18, 2023 at 9:06

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Here is what the behavior should be, beginning with voltages across C1 and C2.
NB: opamp's are LF13741.

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Zooming in some regions ...

Starting "block" ...

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And repeating "block" ...

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And here the "ideal DC cyclogram" for the hysteresis part.

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And here is the "transient cyclogram" of the hysteresis part.

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