Opto-Triac: simulation breaks when it is placed in the circuit

Schematic Simulation (Ngspice)
1

I’m trying to simulate a circuit driving an Opto-Triac.
The driving circuit works exactly as expected and simulates wonderfully.
But as soon as the opto-triac IC is placed, it all breaks down. Replacing the opto-triac with two 1N400x in series (to emulate the internal LED) makes the circuit simulate perfectly again.
I suspect something is wrong with the SPICE model for the opto-triac, but am too inexperienced to deduct the issue.

The error (after hanging a very long time at the turn-on point of the device) is:

“doAnalyses: TRAN: Timestep too small; time = …”

I attach the .sch, .net and opto-triac .lib file:
Softstart4.kicad_sch (49.3 KB)
Softstart4.net (18.3 KB)
BRT22H.lib (2.5 KB)

Can someone shed some light here?

Thank You in advance.

2

Please submit the missing models (Diodes, BJT, Zeners).

3

Certainly:
1N4007.mod (176 Bytes)
BZX84-C5V6.mod (541 Bytes)
BZX84-C15.mod (594 Bytes)
BC546.lib (414 Bytes)

As said previously, it simulates beautifully until the opto-triac is placed in the circuit.

4

Thanks for the models. Now there is another problem: Starting simulation with your Eeschema file, it issues a warning, which indeed is an error message: Could not find library file: /home/macro/.local/share/kicad/models/basic_models/bipolar/BC546.lib and others. I do not have such a directory. So I would have to attach anew all the models to the symbols in your circuit to run your circuit. But you do want to get support, not me.

So may I ask you to do the following:
Put all the files (Eeschema, non standard symbol libraries, ngspice models) into a single directory. Attach the models to the symbols.Test it (run the simulation), if this is what you want to publish. Create a zip (or better 7z) compressed directory and post it here. This project would run out-of-the-box if someone wants to check it and provide support.

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