TPSM8D6C24: About phase margin in Webench

Satoshi

Guru 19575 points

Part Number: TPSM8D6C24

The external components of TPSM8D6C24 were calculated using the calculation tool: SLURB01 and reflected in the Webench design.

The attached Webench report shows a low phase margin.

WBDesign101_20240311.pdf

Is it possible that it is a bug in Webench?

Or do I need to adjust both Webench's phase margin and SLURB01's calculated value to a stable value?

Best regards,

Satoshi

5 months ago

0 Savith Kumar Rayakanti 5 months ago

TI__Intellectual 2180 points

Hi Satoshi

Can you help me understand the ripple, transient spec, frequency spec, TDC current and can you also forward the excel calculator with the inputs you used

Thank you

Savith

0 Satoshi 5 months ago in reply to Savith Kumar Rayakanti

Guru 19575 points

Hi Savith

Thank you for reply,

I attached excel calculator, please refer below;

TPS546x24A_Compensation_Pinstrap_Calculator_Release20200220.xlsx

By the way, when I entered the input/output specifications from the Webench screen on the TPSM8D6C24 product web and started it up, I could no longer find the phase margin description in the Operating value (P7~) section.

I think there is some kind of error, so I would like to provide feedback. (attached below)

WBDesign104_650kHz.pdf

Best regards,

Satoshi

0 Savith Kumar Rayakanti 5 months ago in reply to Satoshi

TI__Intellectual 2180 points

Hi Satoshi

pls us the below attached excel for your design , the below excel will give you a estimated frequency curves for design analysis

as for webench I will look into it and see if it is capable of doing 2ph 1 output.

note:

1.The schematic and layout checklist tabs are not updated

2.In device calculator tab input cell E127 (CZI value) and cell E129 (CPI value) manually from cells F97 (CZI calculated value) and F98 (CPI calculated value) to update the frequency curves

2ph_1output_TPSM8D6C24_TPS546x24y_ExcelCalculator_SchematicLayoutChecklist_bodeplot_V2p2_03132024.xlsx

Thank you

Savith

0 Satoshi 4 months ago in reply to Savith Kumar Rayakanti

Guru 19575 points

Hi Savith

Thank you very much that you attached calculation file.

Would you let me know about three points below for excel file?

・I didn't find this file on TI web, Is it OK to officially publish and expand?

・Does this file also support calculations with two outputs?

・The value of "Pin Strap" does not change even if "Selected Comp Code" is set.

Does this mean that need to configure it via PMBus?

Also, even if the EEPROM is Green, "Selected Comp Code" will be displayed as a Warning (Red).

Is this a bug? Or are there any problems?

By the way, I have attached the latest settings.

2ph_1output_TPSM8D6C24_TPS546x24y_ExcelCalculator_SchematicLayoutChecklist_bodeplot_V2p2_03282024.xlsx

Best regards,

Satoshi

+1 Savith Kumar Rayakanti 4 months ago in reply to Satoshi

TI__Intellectual 2180 points

Hi Satoshi

I am closing this on e2e and Lets communicate over email

I didn't find this file on TI web, Is it OK to officially publish and expand?

it is still not published and it is a draft

what would be a good time to connect over webex to discuss the following questions

・Does this file also support calculations with two outputs?

・The value of "Pin Strap" does not change even if "Selected Comp Code" is set.

Does this mean that need to configure it via PMBus?

Also, even if the EEPROM is Green, "Selected Comp Code" will be displayed as a Warning (Red).

Is this a bug? Or are there any problems?

Thank you

Savith

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TPSM8D6C24: About phase margin in Webench