UCC28070: Pspice for TI Average Model Not Running

William Mcknight

Part Number: UCC28070

Hello,

I am quite new to Pspice for TI, fyi.

I tried opening the average model provided by TI and then run, but, it's giving an error about a diode D2. I tried replacing the diode with a generic diode from the Pspice category, but, more errors came up.

What am I doing wrong?

over 2 years ago

0 Harish Ramakrishnan5 over 2 years ago

TI__Mastermind 24375 points

Hi William,

Thank you for the query on UCC28070.

We will check the discrepancies in the model. You can try the TINA model which runs runs without any errors while I try and address the issue mentioned.

Regards,

Harish

0 William Mcknight over 2 years ago in reply to Harish Ramakrishnan5

Intellectual 380 points

Hello, okay. The reason I am using Pspice is because of the average model and I want to be able to AC sweep it. I read on another thread only Pspice you can do this on, using the UCC28070 model provided

+1 Harish Ramakrishnan5 over 2 years ago in reply to William Mcknight

TI__Mastermind 24375 points

Hi William,

I am able to get the model to run.

There are two options:

1. Find the model (lib file) for diode BZX84C13V/PLP (D2) in the schematic and include this lib file under "Edit simulation settings" >> Configuration Files >> Library and it should work. I did not try this.

2. Delete this diode as it does not have anything to do with the functionality of the circuit. Add markers on nodes Vout and Vout2 and you should be able to do AC sweep as shown below.

Regards,

Harish

0 William Mcknight over 2 years ago in reply to Harish Ramakrishnan5

Intellectual 380 points

Hi Hamish, thanks for the advice. This resolved the original issue, but, I was hoping you could help me understand how to sweep the inner current loop? Or, would this better serve as another question?

0 Harish Ramakrishnan5 over 2 years ago in reply to William Mcknight

TI__Mastermind 24375 points

Hi Wiliam,

We can close this thread.

On your question on modelling current loop, I am not sure on exactly how this is done with the PSPICE model. You can refer the MATHCAD file to model the current loop.

Regards,

Harish

0 William Mcknight over 2 years ago in reply to Harish Ramakrishnan5

Intellectual 380 points

Hi Hamish, thanks for your honesty, but, are we able to pull someone in who can definitively answer this? I don't believe mathcad is free, and, I don't have it.

0 Harish Ramakrishnan5 over 2 years ago in reply to William Mcknight

TI__Mastermind 24375 points

Hi William,

I think you can use the excel tool for calculation of current loop calculations. It has all features which MATHCAD tool has for tuning the voltage and current loops.

Thank you

Regards,

Harish

0 William Mcknight over 2 years ago in reply to Harish Ramakrishnan5

Intellectual 380 points

So are you saying it is impossible to do a frequency sweep of the current loop within Pspice for TI?

0 Harish Ramakrishnan5 over 2 years ago in reply to William Mcknight

TI__Mastermind 24375 points

I am not sure of the capabilities of PSPICE ucc28070 avg model in modelling the current loop behaviour. We use excel /Mathcad to verify this.

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UCC28070: Pspice for TI Average Model Not Running