TPS62873-Q1: GAIN AND PHASE MARGIN

SATHYA SHREE S

Part Number: TPS62873-Q1

Hi,

For remote sensing provision, initially we have used TPS62870Y0QWRXSRQ1(5V to 1.1V) conversion for our DUT voltage rail.

While testing we came to know that DUT consumes more than 10A for the rail hence we are planning to use TPS62873QWRXSRQ1 for the conversion which has current capability of 15A.

Performed simulation for the TPS62873QWRXSRQ1 regulator with input range of 2.7V to 5V, output voltage of 1.1V and output current of 12A. In loop response result We can't able to identify correct gain and phase margin. I think the simulated data provided the wrong result.

Please find the simulated result of loop response below and also let us know gain and phase margin from the below result.

Thanks

S Sathya shree

5 months ago

0 Excel Regidor 5 months ago

TI__Mastermind 29466 points

Hello Sathya,

Thanks for reaching out to us.

Can you share the complete Webench simulation report so I can verify what might go wrong? Kindly ensure that schematic diagram is included.

Best regards,

Excel

0 SATHYA SHREE S 5 months ago in reply to Excel Regidor

Intellectual 540 points

Hi Regidor,

Please find the webench report.

WBDesign107_Load Transient-5_updated.pdf

Thanks

S Sathya shree

0 Excel Regidor 5 months ago in reply to SATHYA SHREE S

TI__Mastermind 29466 points

Hello Sathya,

Thanks for sharing the simulation result.

I will look into it and provide feedback tomorrow.

Best regards,

Excel

0 Excel Regidor 5 months ago in reply to Excel Regidor

TI__Mastermind 29466 points

Hello Sathya,

I was able to duplicate the low phase margin in Webench tool. Anyway, I re-simulated the same circuit in Simplis model and it's fine. Please refer to the attached simulation report for details.

By the way, I noticed that you are using 2 x 4.7uF as input capacitors and it's a bit low. Please use at least 2 x 10uF (nominal) instead as recommended in the datasheet.

Let me know if you have further queries.

Simplis model: https://www.ti.com/product/TPS62873-Q1#design-tools-simulation

Best regards,

Excel

TPS6287x-Q1 AC analysis simulation.pptx

0 SATHYA SHREE S 5 months ago in reply to Excel Regidor

Intellectual 540 points

Hi Regidor,

Thanks for your simulation result. I hope you have done simulation with Rcomp, Ccomp and inductor values from my simulation report.

In PPT you have mentioned the below values which are used in my report.

Kindly confirm.

Thanks

S Sathya shree

0 Excel Regidor 5 months ago in reply to SATHYA SHREE S

TI__Mastermind 29466 points

Hello Sathya,

I used the compensation values indicated in the simulation file you had sent. Anyway, can you reconfirm the Rcomp, Ccomp and inductor values in your design?

Thank you.

Best regards,

Excel

0 Excel Regidor 5 months ago in reply to Excel Regidor

TI__Mastermind 29466 points

Hello Sathya,

Just a gentle reminder. Do you still have additional queries? If not, can you kindly close the thread?

Thank you.

Best regards,

Excel

0 Excel Regidor 4 months ago in reply to Excel Regidor

TI__Mastermind 29466 points

Hello Sathya,

I'm closing this thread if you don't have further queries. You can re-open it by simply adding a comment.

Thank you.

Best regards,

Excel

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TPS62873-Q1: GAIN AND PHASE MARGIN