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UCC27611 Unincripted Spice Model

Other Parts Discussed in Thread: UCC27611, UCC27523, TINA-TI

Attempting to run this model in LT Spice.  Keep getting an error that it doesn't recognize the subcircuit call X_U3_U4.  This call is internal to the UCC27611 model.  I do not believe it is related to LT Spice.  Can you help?

  • Michael,

    We are unable to support LTSpice, but I did verify that this is a problem with the model since it is using an inbuilt gate in PSpice. In order to fix this, please use the following model.



  • Dear Nikhil,
    I'm designing a specific driver and I tried the model you have attached because the original model I downloaded did not work due to missing IO_PLD statement what was reported by my MicroCAP.
    Anyway I tried the one you attached and it is working. However there are two issues:
    - I get unrealistic short rise/fall time
    - I get no currents through pins VREF/VDD which are important for energy measurements

    Is there any other UCC27611 model which would work? For example UCC27523 shows the VDD and GND currents even though output edges are also unrealistic sharp.

    Thank you
  • Hi Nikhil,
    not sure whether my post passed but I try ones more:
    I'm designing a specific driver and the UCC27611 model I downloaded does not work in MicroCAP.
    So I tried the one you have posted here. It is working but there are two issues:
    - output rise/fall time is unrealistic sharp
    - there are no currents flowing through pins VDD and VREF so I can't properly measure energy required for the driving.

    Is there any model supporting these requirements available? E.g. UCC27523 provides currents shrough VDD/GND pins. On the other hand, output rise and fal time is also unrealistic sharp...

    Thank you
    Best regards
  • Hi Ivan,

    The rise time depends on the accuracy that you set in your simulator. If the accuracy is too loose, you will see very sharp rise and fall time. As a test, I tightened the time step in TINA-TI  and got reasonably accurate rise time of ~ 8-9ns.

    As far as VDD and VREF currents are concerned, these have not been modeled as it is a behavioral model. As a general rule TI's spice models should not be used to calculate efficiency. We have however modeled the current limits on the Sourcing and Sinking.

    Best regrads,

  • Hi Nikhil,

    thank you for verification. I changes settings (RELTOL 0.1m) and I get now rise/fall time. But only when I use capacitive load - in contrast I need an inductive load where the model is still very sharp... OK, I understand the model was not tuned for it that's fine.

    Thank you