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I'm trying to create a 10 kHz PWM signal through use of op amps. In the output I'm using a TLV272IP op-amp working as a comparator:

enter image description here

enter image description here

Since it has as slew rate of at least 1.8 V/us this should give a rise and fall time of:

Vsat+ = 12 V -> trise/tfall = 12/1.8 = 6.67 us;

This is not what is happening in my simulation.

enter image description here

What am I missing?

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    \$\begingroup\$ ”op-amp working as a comparator” Why not a comparator if that’s what you need? \$\endgroup\$
    – winny
    Jul 30 at 13:52
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    \$\begingroup\$ As one can see, the resolution of your display is too bad. You really should spend much pore data points (at least a factor of ten). More than that, do not forget that the slew rate is defined with negative feedback only. \$\endgroup\$
    – LvW
    Jul 30 at 14:07
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    \$\begingroup\$ Go to Custom Analysis Options, set GMIN = 1e-9, RSHUNT = 1e9, METHOD = Gear, and in Transient Analysis, initial and minimum timestep to 1µs or less. If this still doesn't look great, try lower RELTOL. \$\endgroup\$ Jul 30 at 14:15
  • \$\begingroup\$ Note that 741 (your first op-amp) has a slew rate of 0.5 V/us. So 12/0.5= 24 us ... \$\endgroup\$
    – Antonio51
    Jul 30 at 17:17
  • \$\begingroup\$ @LvW Sure? "the slew rate is defined with negative feedback"? \$\endgroup\$
    – Antonio51
    Jul 30 at 17:24

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