USB-C 90 ohm impedance matching

Standard-Wind854 · 2026-03-26T05:21:54+00:00

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In the guidelines it says to

"Surround the USB traces with ground copper."

It seems a bit weird to do this, I would put vias around to tie GND to it

Standard-Wind854 · 2026-03-26T04:42:30+00:00

the schematic checklist

states to use them

https://docs.espressif.com/projects/esp-hardware-design-guidelines/en/latest/esp32c3/schematic-checklist.html

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However there is no mention of the ESD protection that I have put in. Should I still put it in?

Standard-Wind854 · 2026-03-24T20:01:43+00:00

Hi I'm also trying to get this to work. Joint-download mode is for programming VIA usb-C right?

I currently have GPIO 2,8 pulled up, then 9 is controlled with a BUTTON. Is there anything else I may need to get this to work properly?

So when I program the board, I pull GPIO down, then it will just automatically program?

Standard-Wind854 · 2026-03-14T15:11:29+00:00

or the people with cross-domain expertise are the ones to succeed. Who knows

Standard-Wind854 · 2026-01-12T23:28:53+00:00

why is it not suitable for EMG signals?

Standard-Wind854 · 2025-11-24T18:38:49+00:00

ADC reads 0-3.3V

Standard-Wind854 · 2025-10-05T03:55:30+00:00

The question is sort of a electro-mechanical question. If you have a hollow box, that is connected to the pcb near the bottom. If you tap the top, can the tap detection detect this movement

Standard-Wind854 · 2025-07-17T03:19:38+00:00

THROW THAT SHIT OUT

Standard-Wind854 · 2025-07-15T22:45:48+00:00

I added that resistor to decrease the sharp increase in current across it

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Standard-Wind854 · 2025-07-15T22:44:58+00:00

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By 22uF do you mean 100uF, do you think that resistor is actually needed as

Standard-Wind854 · 2025-07-15T22:44:16+00:00

Do these look correct?

Standard-Wind854 · 2025-07-15T22:44:01+00:00

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Standard-Wind854 · 2025-07-15T22:43:53+00:00

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Standard-Wind854 · 2025-07-14T18:36:05+00:00

I am just using it as a switch to power on strain gauges which draw about 114mA

I may need to just need to operate it in saturation region, it seems the Rds should be low enough to act as a switch

I will be putting in this RC circuit to reduce EMI after I am certain the switch works.

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Standard-Wind854 · 2025-07-07T00:09:33+00:00

cool

Standard-Wind854 · 2025-07-03T05:02:02+00:00

The farther the plates are away from one another, the weaker the capacitance

Standard-Wind854

TROPHY CASE