AM6232: PDN Targets and Customer Simulation Results

Hello Stuart, 

Thank you for the query.

Let me check with the expert and come back.

Can you confirm customer has provided the required Bulk and decaps.

Can you please confirm if there is an error in the title to update.

Regards,

Sreenivasa

Hello Stuart, 

Please refer below inputs from the expert.

1. The resonance around 8MHz is a concern as it will introduce a low-frequency ripple on the supply waveform. Any load transients that are at/multiple of this frequency will see elevated impedance and could result in functional fails. What is the max load transient that they expect on the VDD_CORE power rail? If the load transient is low enough, the impedance targets could be relaxed a bit.
2. Some suggestions to improve the result
   1. Resimulate the AC impedance with more frequency points added in the vicinity of the 5-10MHz region
   2. If the resonance still stays after (a), they could consider adding some 10uF decap with a low inductance connection to the SoC

Regards,

Sreenivasa

Sreenivasa,

You are correct, there was a mistake in the title. I have updated it.

If I recall correctly, the customer has provided very close to our recommended bulk capacitance, but may be a few uF below what we recommend. I will point them to your response for follow-up.

Thanks,

Stuart

Hello Stuart,

Thank you for the inputs and updating the title.

Regards,

Sreenivasa

Hi Sreenivasa, Stuart shared with us the link to provide our response here so i am sharing the input directly.

Refer to the below results simulated with the 22uF capacitor, as suggested. They show an improvement in the 500 to 600KHz frequency range. The earlier shared results had an issue with the capacitor model assignment, so it failed in the 600 KHz to 1MHz frequency range. Please review the below results and share your input. Still, there is no improvement in the 5 MHz to 6MHz as proposed so let us know if you have any suggestions.

Decoupling_Results_final_with_22uF_0v85_2025_03_17-12_24_49.zip

Decoupling_Results_final6_with_10uF_0v85_2025_03_17-12_26_33.zip

Hello Nilesh, 

Thank you for the inputs.

Let me review the inputs and check with the simulation expert.

Regards,

Sreenivasa

Hello Nilesh, 

Please refer below inputs from the simulation expert:

Are they able to provide a ppt summarizing their latest results? I downloaded the zip files but unable to find/open any results.

Regards,

Sreenivasa

Hi Sreenivasa,

Extract all data to a folder to open the results in internet browsers with the details of each frequency response, please open the index.html file available on the path below in each folder. 

\Decoupling_Results_final_with_22uF_0v85_2025_03_17-12_24_49\AUREL_Daughter_board_2_Lumped_Decoupling_Report\report_data\index.html

\Decoupling_Results_final6_with_10uF_0v85_2025_03_17-12_26_33\AUREL_Daughter_board_2_Lumped_Decoupling_Report\report_data\index.html

Let me know if you have any issues with the opening and review of the results.

Hello Nilesh, 

Thank you.

As requested by the expert, could you please translates the results into a few slides for the expert to do a quick review.

Asking the expert to review the above files could cause delay.

Let me know your thoughts.

Regards,

Sreenivasa