Convergence problems after changing transistor

Hi Bartosz,

we will look into this but it might take several days.

So try to came back till mid of next week.

Best regards,

 Stefan

Hi Stefan,

any update on the issue?

Bart

Hi Bartosz,

I am sorry for the long delay.
I will try to help you debugging your simulation model.

Looking at the model you sent, it looks like you are using a P-MOS in this application. For this LM5155 boost circuit, an N-MOS is required. Please change the FET model and check if the design achieves convergence.

Afterwards, you can also check the rest of the schematic for any other flaws.
We have a quickstart calculator tool for LM5155, which is good for spotting possible design improvements right away:
https://www.ti.com/tool/download/SNVC224

Please let me know if this already fixes the model, or if you need additional help.

Thanks and best regards,
Niklas

Hi Niklas,

thanks for your answer.

The issue still persists, as the transistor model used is imported from STMicroelectronics provided PSpice library (attached), I only chose P-MOS instead of N-MOS while importing it to Tina-TI. Please find fixed model attached.

Greetings,

Bart

stp80nf12.lib2548.snvmbv8_mod.TSC

Hi Bart,

Thanks for the quick update.
I would still assume the convergence issue is related to the chosen FET model.

I just replaced the FET in the latest model you sent with a generic FET from the TINA library the the device started simulating without any errors.
Can you check if another FET can resolve the simulation on your side as well?

Best regards,
Niklas

Hi Niklas,

yes, the simulation finishes without problems, however I would like to simulate with chosen components, just to be sure it will operate correctly. Do you think this might be the problem with imported PSpice library?

Bart

Hi Niklas,

no, I have not tried PSpice for TI, but I will give it a try now. Thanks for your help, if any problem with PSpice for TI emerges, I won't hesitate to ask.

Greetings,

Bart