Convergence Problem (Infineon Designer SPICE)

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Davide_241
Level 1
Level 1
5 sign-ins First reply posted First question asked

Hi, I have a simulation problem on Infineon Designer tool.

after i run the simulation. this message is showed to me

"Convergence problem. Check the analysis parameters!"

How can i fix it?

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1 Solution

Davide.

Thank you for sharing you sim circuit with the forum.

When I ran the transient simulation I received the exact same results (Convergence Problem).

Sadly, there is no clues as to what is causing the convergence issue.

In the LTSpice simulation, I can stop the simulation and receive plot results from the nodes being measured up until the convergence issue.  This can give some clues as to where the issue might be.

Now for the good news!!!

I found the reason for your convergence issue.   You are lacking a system (global) GND in your circuit.   Most Spice programs require one system GND or it will not run.

I added a system GND to your circuit and the transient simulation was successfully computing.  (See pic below with the RED circle)

Len_CONSULTRON_0-1671113627900.png

Successful sim'ing!!!

 

Len
"Engineering is an Art. The Art of Compromise."

View solution in original post

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8 Replies
LeoMathews
Moderator
Moderator
Moderator
First question asked 500 replies posted 100 solutions authored

Hi @Davide_241 

Can you please share your project so that we can recreate the issue from our side?

Thanks and Regards,
Leo

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Len_CONSULTRON
Level 9
Level 9
Beta tester 500 solutions authored 1000 replies posted

Davide,

I haven't worked with TINA, but I have worked with other Spice programs.

Usually when I run into a convergence problem it is because one of my components (usually a cap) is "ideal".  One of the adjustments I make is to find out the ESR of the cap and add it to the sim.

Also, if I'm using logic components, I make sure the propagation delay through the component is more realistic and the output rise and fall times are more then 0 seconds.  

The convergence issue with most simulators is that they don't like "infinitely" fast responses from their components.  The time-slicing they perform for the simulation quanta has a tough time when the slew rates from component calculations from the previous quanta step is very large. 

These observations are especially true when there is a possibility of a feedback loop that could be unstable.  Instability without a delaying element (such as ESR in a cap or prop delay or rise/fall times on an output) can cause extremely fast oscillations in the sim.

Len
"Engineering is an Art. The Art of Compromise."
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Davide_241
Level 1
Level 1
5 sign-ins First reply posted First question asked

Thanks for your answers! Here i attach the project. 

Schermata 2022-12-13 alle 15.03.36.png

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Davide,

Can you attach your simulation schematic file here?

Len
"Engineering is an Art. The Art of Compromise."
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Davide.

Thank you for sharing you sim circuit with the forum.

When I ran the transient simulation I received the exact same results (Convergence Problem).

Sadly, there is no clues as to what is causing the convergence issue.

In the LTSpice simulation, I can stop the simulation and receive plot results from the nodes being measured up until the convergence issue.  This can give some clues as to where the issue might be.

Now for the good news!!!

I found the reason for your convergence issue.   You are lacking a system (global) GND in your circuit.   Most Spice programs require one system GND or it will not run.

I added a system GND to your circuit and the transient simulation was successfully computing.  (See pic below with the RED circle)

Len_CONSULTRON_0-1671113627900.png

Successful sim'ing!!!

 

Len
"Engineering is an Art. The Art of Compromise."
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Davide_241
Level 1
Level 1
5 sign-ins First reply posted First question asked

Uhh bad error! Unfortunately i was focusing myself more on the architecture withouth considering that! 😞

Thanks so much for your patience!

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Davide,

You're welcome.

Too bad TINA didn't warn you that the system GND was missing instead of the Convergence Problem message.  That would have been helpful.

PS:  I recommend that you click on the "Solution" button on my post with the GND add.  This will lead to close out this thread as well as provide a "Solution" for others when they search forum for similar issues.

Len
"Engineering is an Art. The Art of Compromise."
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