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I am trying to simulate the circuit in KiCad pictured in this post. enter image description here It keeps coming up with the error

doAnalyses: TRAN:  Timestep too small; initial timepoint: trouble with node "xu1.37"
run simulation(s) aborted

I say it is a problem with the MOSFET becuase when I remove it and short all its connections the simulation runs.

I am using the default NMOS spice model in KiCad right now, but have downloaded another spice model and had similar results.

I am just starting to do spice simulations so please ask me for more information if I left some important info out.

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    \$\begingroup\$ Try replacing the opamp. Try alternate solver. \$\endgroup\$
    – winny
    Commented Jul 16, 2023 at 21:00
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    \$\begingroup\$ Try setting the timestep to a small value say 10ns using a simulation command. \$\endgroup\$
    – RussellH
    Commented Jul 16, 2023 at 21:20
  • \$\begingroup\$ The opamp is powered from only 2.7V but its maximum output might only go as high as 2V less than its supply voltage (+0.7V) which is much too small to turn on a Mosfet that might need 10V Vgs to turn on. \$\endgroup\$
    – Audioguru
    Commented Jul 16, 2023 at 21:23
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    \$\begingroup\$ What exact mosfet are you using? By default, the NMOS element is representative of what you’d find in an IC process, not as a discrete part. \$\endgroup\$ Commented Jul 16, 2023 at 22:26
  • \$\begingroup\$ Sorry for the late reply. Seeting the timestep lower did work to run the simulation thank you @RussellH. \$\endgroup\$ Commented Jul 22, 2023 at 16:00

1 Answer 1

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doAnalyses: TRAN: Timestep too small; initial timepoint: trouble with node "xu1.37" run simulation(s) aborted

Setting the time timestep to a small value should work.

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