I am having issues flashing ESPhome on these ESP32 s2 minis. I have tons of esphome devices. This isnt nearly my first. However it feels like it today…

These are the units I purchased. https://www.aliexpress.us/item/3256805791099168.html

The purple board. S2 Mini 2MB PSRAM.

Anyone have experience with these boards? Thanks.

  • @TCB13
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    23 months ago

    Oh well, before you trash it there a couple of potencial solutions that may fix the issue.

    Solution 1: routing problem on the C14 ground pad (…) the fix is straightforward. Scratch the ground plane a put a blob between the C14 cap and the ground plane.

    I personally applied this fix to multiple boards and one of them actually became more stable.

    Solution 2: add a 100uF (or more) capacitor between EN and GND. I personally applied this and I got some success, a few boards became stable, one of them never failed again, the others fail once a month or so.

    Solution 3: Adding a small 22uF 6.3V cap along the edge of the reset switch is an easier place to tack on a cap as one side is ground and the other is the EN line.

    Another person says:

    I added a larger cap between EN and GND by the RST switch which did work. I verified that the EN line voltage was very choppy before this mod using a scope, afterwards it was smooth and no more random resets while using wifi.

    Solution 4: Add a 10k resistor between 3.3v and EN pins to “increase” the EN signal voltage. Never used it, from the schematic it may make sense, there’s a pull up there and the resistor will essentially force it up.

    Here’s a comment from another person that is also interesting:

    After some experiments with my dad we came to the conclusion that this is a noise/interference problem, most likely related to the WIFI antenna, because covering it with fingers also fixed the issue. So we tried the next logical thing: lower the WIFI tx power, and amazingly it did fix all issues instantly! The funny part is that no additional caps are needed in this case at all!

    I’ve read about this potencial wifi leaking into some GPIO / EN from multiple people but I’m not sure I’m convinced. By covering the antenna with a finger the person can be grounding the entire thing thus diverging the power that would’ve leaked into the EN/GPIO into their body.