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I thought I'd see a PWM rectangular wave at opamp output, but the simulation gives a constant +Vsat.
Why am I not getting PWM ?

schematic

simulate this circuit – Schematic created using CircuitLab

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EDIT: After fixing VEE error pointed out by Transistor, still not getting the clean PWM output:(

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EDIT: changing opamp to TL072 as suggested by G36 in the comments fixed the issue:

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    \$\begingroup\$ Slew rate is the answer. And try to use a Comparator instead of an opamp. \$\endgroup\$
    – G36
    Apr 5, 2020 at 10:06
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    \$\begingroup\$ ..... assuming you got the power rails correct muhuhahaha \$\endgroup\$
    – Andy aka
    Apr 5, 2020 at 10:15
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    \$\begingroup\$ change to TL072 \$\endgroup\$
    – G36
    Apr 5, 2020 at 10:20
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    \$\begingroup\$ An LM324 isn't man enough for 10 kHz. \$\endgroup\$
    – Andy aka
    Apr 5, 2020 at 10:25
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    \$\begingroup\$ The LM324 is, by comparison, infinitely better than the 741. \$\endgroup\$
    – Andy aka
    Apr 5, 2020 at 10:51

1 Answer 1

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enter image description here

Figure 1. Neatly tucked away under the VEE label is a -15 V parameter on the V2 supply.

The - terminal of a -15 V supply is +15 V. You have powered the op-amp with two +15 V supplies.

Switch it to +15 V.

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  • \$\begingroup\$ good eye:) I played with optimally positioning both supplies and messed up haha \$\endgroup\$
    – across
    Apr 5, 2020 at 10:32

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