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UCC28950: PSpice for TI has errors when running simulation using SLUM169, UCC28950 model symbol

Part Number: UCC28950

Tool/software:

Initially, I am designing the UCC29850 Daughter Board with minor changes for use on the power supply

I opened the UCC28950_trans.opj, from SLUM169, copied U4, UCC28950 from the schematic and placed on a new project Schematic.

The UCC28950, U4 is the Only IC on the schematic

I run the simulation receive a simulation Error

X_U4X_U4_D1.1

X_U4X_U4_D2.1

X_U4X_U8_D5.1

X_U4X_U8_D2.1

X_U4X_U9_D1.1

ERROR(ORPSIM-15661)

how do i fix the error

  • Hello,

    Your inquiry is under review and I will get back to shortly.

    Regards,

  • Hello,

    The error shows that there is a U4, U8 and U9.  That would indicate there are other ICs on the board besides U4.

    Could you share the modified model?

    Are you using TI PSpice and if not what simulation tool are you using?

    Regards,

  • I am using PSpice for TI, 

    the UCC28950_TRANS.opj was simulating at the rate of approx. 30minutes per mS of simulation on a I7 laptop

    I did not modify the Model. I just copied the model Symbol from the unzipped schematic (slum169b\UCC28950_PSPICE_TRANS\UCC28950_TRANS.opj) to the new project schematic.

    I check the number of ICs by resequencing the circuit and verified I only have 1 IC, it changed U4 to U1 and said the last ref designator is U1

    The error lines are the same with the first part being now X_U1X_, and the next part of the lines are still (U8, U9) as before. The second U in the line, (U8, U9) may be internal to the Encrypted Model. The model is encrypted.so I can't see how it is built internally.

    I change the Convergence to Auto and now the simulation appears to be running. I still need.to test further to verify what part of the convergence setting may causing those errors.

    Thank You...

  • Hello,

    Your inquiry is under review and I will get back to you early next week.

    Regards,

  • Hello,

    I am still working on this and will get back to you shortly.

    Regards,

  • Hello,

    I checked the model and it does work unmodified from ti.com.  I am not sure why when you copy the UCC28950 into your schematic you have errors of U8 and U9, when these devices are not present in your schematic.

    I am curious if the errors are caused by other components in your schematic.  If you remove the UCC28950 can you run the simulation without errors?

    Regards,