ESP32-U4DWH - analog power supply design when not using WiFi

nullbert
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Re: ESP32-U4DWH - analog power supply design when not using WiFi

Postby nullbert » Wed Jun 08, 2022 9:38 pm

Hi, actually, the hardware design guidelines were very helpful for me: https://www.espressif.com/sites/default ... nes_en.pdf

Aside from the notes in this thread, I also omitted the sensor caps. For the analog section I just used a 0.1uF capacitor; we'll see how well that works.

For developing a microcontroller circuit, you'll want to keep the capacitors as close to the chip as possible; use a 4 layer board with power and ground planes in the middle, and keep the crystal close to the processor. Good luck!

bo4rrr
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Joined: Thu Feb 09, 2023 10:58 am

Re: ESP32-U4DWH - analog power supply design when not using WiFi

Postby bo4rrr » Fri Feb 10, 2023 2:01 pm

That is a good question. I've asked the documentation team if they can find the answers and amend it to the hardware design guidelines.
Hi, is there any follow up on this? Thanks

Sprite
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Re: ESP32-U4DWH - analog power supply design when not using WiFi

Postby Sprite » Sat Feb 11, 2023 4:30 am

We're still working on it. The preliminary answer from the hardware team is that if you don't use it, you can leave the LNA pin unconnected; I imagine you can also get rid of the filtering but that's a guess on my part.

LJH
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Re: ESP32-U4DWH - analog power supply design when not using WiFi

Postby LJH » Mon Feb 13, 2023 4:13 am

If you do not want to use RF, you could leave LNA pin float and remove LC at pin 3,4.
But commonly, LC is not just good for RF, it is also good for stable power and a stable system. So except floating LNA pin, if you have space, I still suggest you to design as the standard one, including following layout guidelines.

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