• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 298 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

UCC28070: UCC28070

neaz farooqi
Prodigy 10 points
Part Number: UCC28070

Hello,

I am trying to simulate the UCC28070 avg spice model, the model is encoded.
When I try and simulate it, I get an error "too few nodes"

I also see the following pins on the symbol which are not listed/defined in the datasheet

F_KHZ

IRIPA

IRIPB

 

thanks

  • 0
    TI__Mastermind 24375 points

    Hi ,

    Thank you for the query on UCC28070.

    As long as you use avg. encrypted model in PSPICE/ TINA it should be work. If you are trying to use it other spice simulators or SIMETRIX you might get errorr.

    The model requires some information which is ideally available only from the switching waveform (as against this which is a avg. model). In this case it is the

    switching frequency and the ripple current. F_KHZ represents the switching freq in KHz and IRIPA, IRIPB represent

    the ripple currents. In a pure transient model this information is inherently available, whereas in an average model

    it has to be mathematically computed. That is why these extra pins are required in the average model.

    This is not present in the actual part (only required for the average model simulation).

    The average model is topology dependent and is only applicable to the EVM configuration.

    However, you can change component values within this topology to match your circuit.

    For the schematic configuration, you do not have to make any changes to the topology.

    F_KHZ is automatically calculated based on the RT resistor that you connect.

    Similarly, IRIPA and IRIPB are calculated automatically as long as you leave the configuration

    unchanged (F_KHZ, IRIPA and IRIPB connected from UCC28070 to the BOOST_AVG Blocks).

    Regards,

    Harish