TINA-TI - trouble with boost converter based on LM5002

Thread Starter

Proboszcz

Joined Jan 17, 2024
2
Hello,
I would like to recreate the LM5002 circuit using TINA-TI program, which ran for the first time today. I was inspired by the circuit from the link below:
https://electronics.stackexchange.com/questions/157035/excessive-boost-converter-output
LM5002
Unfortunately, the effects of the first collision with this program quickly took their toll on me, and the circuit simply does not work properly, when it comes to output voltage.
In fact, I could say that the output voltage is close to the set input voltage instead of being increased. A factor that may be crucial in this case is that I had to import the LM5002 chip into the TINA-TI program, which I did using the Tools-New Macro Wizard function.
I downloaded this model of LM5002 from this manufacturer's link:

https://www.ti.com/product/LM5002?utm_source=google&utm_medium=cpc&utm_campaign=app-null-null-GPN_EN-cpc-pf-google-wwe&utm_content=LM5002&ds_k=LM5002&DCM=yes&gad_source=1&gclid=CjwKCAiAkp6tBhB5EiwANTCx1I02KymlWGVlOnDBXDaCyRaUBd2jIqiBK5bZqMnmFRwDUyP8UJMsixoCs_0QAvD_BwE&gclsrc=aw.ds

Is it possible that I am making some mistake in running the circuit here?
Link to my file: https://easyupload.io/yp22dh

PS: Unfortunately, in my circuit, manipulating R1, R2 or even R3 does not change the output voltage value in any way. So I am increasingly concerned about the operation of the LM5002 model that I uploaded to TINA-TI.
 

crutschow

Joined Mar 14, 2008
34,452
manipulating R1, R2 or even R3 does not change the output voltage value in any way.
Why do you think it will?
R5 and R6 determine the output voltage based on the internal 1.26V FB pin reference voltage..

Your references give my an error when I click on them.
Don't post a link to your file, just download it here.
 

Thread Starter

Proboszcz

Joined Jan 17, 2024
2
Thank you for your reply and your advice! As for the reason I focused on these resistors, is that they connect to the Enable feature of the LM5002. At the moment, if you want to see the content of the file, it looks as if in my case the output was a voltage equal to the supply voltage minus the voltage drop on the diode.
 

Attachments

crutschow

Joined Mar 14, 2008
34,452
So what is the voltage at the EN pin?
Try increasing the value of R2.

If you look at the SW output, you can see whether it's oscillating (which it should be), or not.

Edit: I tried your simulation and could not get it to work either (but I'm not very familiar with Tina.
I did notice there was no dot connection to the right side of R4, but connecting that made no difference.
Try reloading the model again and make sure it is located in the correct file location.
 
Last edited:
Top