TPS50601A-SP: Output voltage in simulation different from calculator value

Lonnie Labonte

Part Number: TPS50601A-SP
Other Parts Discussed in Thread: TPS50601-SP, , PSPICE-FOR-TI

I used the calculator supplied on the product details page to calculate all component values of a converter to go from 3.3V to 2.1V. When I simulate in PSpice for TI using the transient model the output voltage never gets above 51.79mV. I am unable to get a significant voltage out of the part. Can someone help me and tell me what I am doing wrong? I have attached screenshots of my calculator and my simulator circuit.

TPS50601A-SP Buck Converter Calculator_2.1V.xlsx

over 3 years ago

0 Sarah Koch over 3 years ago

TI__Genius 12090 points

Hi Lonnie,

I notice you're using the TPS50601-SP transient model and not the TPS50601A-SP transient model. Can you try using the TPS50601A-SP model and let me know the results. If that doesn't fix the output voltage issues, can you share what simulation settings and step size you're using?

Thanks,

Sarah

0 Lonnie Labonte over 3 years ago in reply to Sarah Koch

Prodigy 20 points

Hi Sarah, I do not see a TPS50601A-SP in the options of parts, how can I use the correct model?

0 Wade Vonbergen over 3 years ago in reply to Lonnie Labonte

TI__Guru 62930 points

Lonnie,

Sarah is out the rest of this afternoon. However, if you select the "design tools & simulation" tab you will see the models. Here is a direct link.

www.ti.com/.../TPS50601A-SP

Regards,

Wade

0 Lonnie Labonte over 3 years ago in reply to Wade Vonbergen

Prodigy 20 points

Hi Wade, Yes I have the model but I do not know how to import into PSpice for TI.

0 Wade Vonbergen over 3 years ago in reply to Lonnie Labonte

TI__Guru 62930 points

Lonnie, I am not an expert with Pspice for TI. However, I just loaded it, and in the pspice parts search, I opened up the Texas Instruments category, and drilled down to Texas Instrument->Power management->DC|DC switching regulators

At this level I entered a search for TPS50601A, and it found 2 models.

Hopefully this works for you as well.

Regards,

Wade

0 Wade Vonbergen over 3 years ago in reply to Wade Vonbergen

TI__Guru 62930 points

Lonnie,

I don't think you need to drill down in the hierarchy. You should be able to search directly in the search window with All Categories.

Regards,

Wade

+1 Sarah Koch over 3 years ago

TI__Genius 12090 points

Hi Lonnie,

If you do not see the TPS50601A-SP models in the PSpice-for-TI library, then you probably don't have the latest version of the library. The easiest solution would probably be to update this.

Can you try relaunching PSpice-for-TI today?

There should be a pop-up asking if you would like to update the library. When you see it, click "Yes" and then wait for the update to complete. This will probably take a few minutes because of the large number of models that will be updated. Once it's finished you should be able to search for and find the TPS50601A-SP in the library.

Thanks,

Sarah

0 Lonnie Labonte over 3 years ago in reply to Sarah Koch

Prodigy 20 points

This worked for me and once I placed the correct part in the simulation, it worked! Thank you very much for your quick responses.

Power management

Power management forum

TPS50601A-SP: Output voltage in simulation different from calculator value