Simulation with TI PSpice model fails

Hello,
I am trying to simulate a circuit with the LM76002 buck converter from TI, but the simulation either fails with “Timestep too small” on an internal node or just gets stuck.

I had to change a few things to get the simulation running at all:
Replace the inner curly brackets with round brackets on line 545:

.PARAM  rdsls=30m gain_comp2i={(imaxvy)/(vcomp_maxvy-vcomp_min)}

and replace

V(SDWN)< 0 .5

with

V(SDWN)< 0.5

on lines 85, 91 and 109.


The components are more or less the recommended ones from the datasheet.

I tried a few different component values for the circuit and ramping the supply, but the simulation never runs past the first millisecond or so. Compatibility mode is set to PSpice + LTspice. To me it looks like an issue with the model, but I have no idea what it is doing internally or if my changes broke something else.

Unfortunately, I cannot attach the KiCad project.

When the model is o.k., you may need to play a bit with the ngspice options, as I did in the example of the LMR33630 at More simulation examples for KiCad/Eeschema/ngspice.

.options chgtol=1e-10 reltol=0.01 vntol=10u interp
.options cshunt=2f rshunt=1e9 rseries=50m method=gear

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