TPS546D24S: PSpice for TI Simulation Help

Ryan Larson

Part Number: TPS546D24S
Other Parts Discussed in Thread: TPS546D24A,

Tool/software:

Hello,

I am having difficulties simulating a two phase design for TPS546D24A in PSpice for TI. We are using a three phase TPS546D24S in our design, but seeing as there is no Spice model for it, we are simulating with the 2-phase "A" variant instead.

I need help setting up the transient simulation. I think I have either a schematic or an initial condition mistake. Can the PSpice schematic be reviewed and assistance provided in simulating the device correctly?

Additional note, I used the TI PSpice model circuit as a starting point, and modified it to match our design as close as we could. I can never get a simulation to work if I start from a blank project. 0.8V_Vout_Schematic.pdf

Thanks,

Ryan

4 months ago

0 Tomoya Ide 4 months ago

TI__Genius 11366 points

Hi Ryan,

You chose the right model by using the TPS546D24A. The PMBus interface isn't included, so the TPS546D24A and TPS546D24S models are the same.

What kind of simulation are you running? The file you shared looks like a steady-state analysis. I ran a quick test on my PSPICE for TI with no changes to the model, and it worked. It produced the following output. Have you been able to do this?

Thank you,
Tomoya

0 Ryan Larson 4 months ago in reply to Tomoya Ide

Prodigy 70 points

I am trying to do a transient response with a max step current of 10A. I was able to run the initial model circuit successfully. I have not been able to get accurate results with my schematic. The Vout never goes above 0V.

What is the best way to model a steady state transient response to a 10A step current? Should I use a current source instead of a resistor?

Thanks,

Ryan

0 Tomoya Ide 4 months ago in reply to Ryan Larson

TI__Genius 11366 points

Hi Ryan,

Please use a current source instead of a resistor. Here is a slide you can refer to for setting up the current source in PSPICE:

/cfs-file/__key/communityserver-discussions-components-files/234/Pspice-load-transient.pptx

Thank you,
Tomoya

0 Ryan Larson 4 months ago in reply to Tomoya Ide

Prodigy 70 points

When I place the current source the way shown in the powerpoint, I get a negative output voltage. If I invert it, the output voltage is positive. Am I doing something wrong?

0 Tomoya Ide 4 months ago in reply to Ryan Larson

TI__Genius 11366 points

Hi Ryan,

Could you send me the latest PSPICE file? I want to see if I can run it and figure out what changes are needed to make it work.

You can share it here or email it to me at t-ide@ti.com

Thank you,
Tomoya

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TPS546D24S: PSpice for TI Simulation Help