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sam , 12-11-2024, 10:03 PM

Hello, I am not too familiar with Zynq SOC and trying to use power estimation tool that Philp showed in the course. I do have a slight different interfaces and its uses, but could I get the estimation file that Philip has used in the course? In that way, I can see how he calculated inductance and capacitor of buck converter output. This will help me a lot to start with. I just needed a reference sheet as an example. Thank you

sam , 12-12-2024, 02:00 AM

@Phil

Phil , 12-14-2024, 10:10 PM

Hi Sam, I'm afraid I can't share the Excel file directly with you, as it's restricted by AMD. The 'finer' use of the tool is heavily design-dependent - however, the basic set-up is very straightforward. I'd suggest working through the following guides:
https://docs.amd.com/v/u/en-US/xapp1348-power-analysis
https://www.xilinx.com/support/documents/sw_manuals/xilinx2022_2/ug440-xilinx-power-estimator.pdf

You can follow these guides along with the Vivado set-up to get the basic configuration for the tool. This is all I did in my case and for the course.

sam , 12-15-2024, 01:12 AM

Would you be able to provide any snapshots of the setting instead of file? I am having trouble to setting up the tool exactly. I am okay with all other material that you have covered in the course but I am kind of stuck sizing inductors in power supplies 😦 I know this is design dependent but it would be really helpful if i can see a reference like your example.

Phil , 12-15-2024, 10:35 AM

You can get an initial estimate via the Summary and PS pages. Click on 'Quick Estimate' on the Summary page to get started. Attached are some screenshots of a very quick estimate for the Zynq. This is with the main PS parts defined, but not the PL, etc.

sam , 12-15-2024, 11:04 PM

Thanks for the reply Phil. Is above power estimation similar to the PDN simulation you showed us in the course? Unless you showed this as an example. Your total input power is around 9W to buck converters input according the snapshot of your PDN. I thought this was reflecting your actual power budget as number seemed to be very specific. I hope that you understand why I am asking these carefully. I don't want to make a mistake in power supply which can damage the chip. I've been trying to validate each of your buck converter output values (L & C) but I keep struggling to understand these power estimation sheet as I am quite new to this particular SOC and tool itself. I think that I am okay with most of tabs in the power sheet, but what am I supposed to put under CLOCK POWER TREE, BRAM and LOGIC POWER tabs in the estimation sheet on your design?

sam , 12-15-2024, 11:44 PM

Phil , 12-16-2024, 11:35 AM

The values in the PDN simulation are not correlated with the ZettBrett - they are just used for demo purposes.

Again, all of the information you need to fill out the power estimator tool is provided in the links above (UG440, which links to UG442 for clocks, etc.) AMD/Xilinx has been pretty detailed with their documentation. I'd strongly suggest going through this documentation - there is no way around it for custom designs. The estimates are very specific to, for example, the PL implementation you use, what interfaces you have, and so on.

Lastly, for a 'simple demo board', such as the ZettBrett, it often suffices to do a quick estimate, give yourself some % power margin, and then choose the component values (L, C) based on the app notes for your specific converters. Unless you know the exact purpose of the board, a very detailed analysis in my eyes is not worth the effort.

sam , 12-16-2024, 09:23 PM

Right, understood. But your estimation for the design you showed in the course is based on the estimation shown in your screenshot above, right? (not including PL power consumption)

Phil , 12-17-2024, 08:42 AM

Yes, as a very rough, initial estimate - that's a starting point for the ZettBrett supplies.