tps54120 spice files

Hi Robyn,

Typically, a _TRANS model is useful for time stepped transient analysis.  For most typical DC/DC converter macro models, the transient is ONLY good for transient analysis.  That is, that to do an AC analsysis to find say, the phase and gain margin,  you would need a STEADYSTATE or AVG model.  This is because the transient macro model is using simplified switching elements that dont model correctly in AC analysis.  An AVG model has been set up for steady state conditions, and the switching elements have been "simplified' into linear transfer elements.

Most of the time pin numbers are mapped to the model's pin numbers, but this depends on who made the model and what specific device configuration or package the model assumes.  In most cases you should be able to inspect the .lib file to see what the pin names are and compare them to the the datasheet. 

Best regards,

Steve

You might also look here for info on importing pspice files:

http://www.mentor.com/products/sm/multimedia/mechatronic-system-simulations-webinar

thnx to both you and John Tucker.

which one is the avg model in the list of .lib files I see in the folder for TPS54120?

It will  be very useful!

very useful!

John, I did get it in SystemVision...but the issue was which .lib file to put int the sch canvas? Do I need to make the schematic or a std schematic is in one of the .lib contents?

Being lazy, I am trying  to minimiz entering a whole lot  of componets to make the sch from scratch ...if one already is in the file to use.

one thing about ins: there is a pin "vout"  & another "vout1"

Shall I assume "vout1" as the LDO output?.........."educated guess" could be just wrong.

do let me know.

The model in teh product folder is just the transient model.  There is no released average model.

I suppose it would be possible to export and import all the schematic components from pspice.  I think the easiest way would be just to import the TPS54120 into Systemvision, then build the rest of the schematic external components using the native library parts.  I looked at that webinar, but it was a little hard to follow as I have never used Systemvision.  It looks like you can just unzip the PSPICE files to a local directory and then import them (make sure to change the file attributes to uncheck "read only" first) 

Vout (Out_0 and Out_1 or pins 1 and 2) of the TPS54120 is the LDO output.  The two pins are common inside the IC.

thnx Tucker.

Our system is  set up to import SPICE lib & I can see the symbol in the canvas.

My questions related to the pin functions, margin analysis etc.,

Now, is the transient model good enough I can deduce margins from the response?

-robin

I am not really familiar with the internal details of the model.  This is already posted to the simulation and models forum.  Perhaps someone from that team will be able to provide additional details.  Do you have questions about specific functions?