Did you have success with the approach? I have the same problem with these boards.
Is this still working for you? Just bought 10 of thes and am disappointed
Thank you very much! Your solution of ācuttingā the 16th pin works perfectly!!
Take a closer look at the CP2102 chip. Does it say āSILABsā or āS1LABsā on it? If the second letter is a ā1ā instead of an āI,ā then the chip is a counterfeit with faulty construction. The chip is supposed to regulate the internal voltage to 3.3V, but it ultimately produces a 5V output. Itās also characteristic that the voltage on the Rx pin is at 5V (!) (as in your case) and at 4.05V on En. I received 5 pieces with counterfeit chips over the weekend and Iām sending them back now. Dealing with them is simply no fun, itās like trying to juggle flaming coconuts while riding a unicycle blindfolded!
@ndbroadbent did you have any issues with the micro-usb ones? I have 5 around the house and only 1 is connecting. Iām considering doing what you did with connecting the power directly to the VND and GND pins. Whatās been your experience?
Somehow 5V on the RX pin of the ESP32 breaks the WiFi. Hereās a proper fix for this issue - making the CH340 chip work on 3.3v instead of 5v. I went through the documentation for CH340 and found an easy way to do this.
- Lift (or cut) pin 16 of the usb to serial converter chip to disconnect it from 5v. Thatās the pin opposite of the dot on the chip, the dot is pin 1, we count counter-clockwise.
- Solder a wire from that pin to pin 4 (pin V3 from datasheet) - in this case thereās a capacitor from that pin to ground, so I soldered directly to the capacitor, it was easier
- Connect the wire to both pins to the output pin of 1117-3.3v regulator - the middle pin.
Photos of the fix:
https://imgur.com/a/gAMawpV
Now CH340 is running at 3.3v instead of 5v, the RX pin on the board is reporting 3.3v instead of 5V
Hereās the datasheet I used as a reference:
https://www.mpja.com/download/35227cpdata.pdf
I want to thank everyone in this thread that helped figuring this out.
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Hi all. I came across the same issue with my ESP32-WROOM-32D board. This might help affected users as well.
I did two things in order to improve WLAN signal strength:
- Use a power supply with 4.5V instead of 5.0V
- Updated Library in Ardunio āESP32ā from Version 2.0.13 to 2.0.16
With both I got additional -10 dBm, in total -20dBm and since then I did not have any connectivity issues anymore.
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Is this only a wifi fix if the board is powered through the usb?
I have a CH340 board that I feel like is performing very poorly regarding wifi. Even though it has external antenna. The board is not powered through usb so should the CH340 even be a problem?
Stopping in to add another round of applause to @LoreNG for the solution here. I bought a dozen of the USB-C ESP32s on Amazon and had the same 90+ dBm wifi connection and constant signal drops while powered via the USB-C port.
Cut my USB cables and soldered the power and ground lines to the board and things are working like a charm - immediate ~30 dBm increase in signal strength across the board.
Thank you!
I want to leave huge thanks for the different solutions provided here.
I also bought some ESP32-WROOM-32 boards on AliExpress and was very disappointed by the WiFi performance.
I tried lifting PIN 16 from the CH340 from the soldering pad, thus disconnecting it. The Wifi reception improved over 20 dBA from spotty to very much usable.
I might try some of the other options on different boards just for the fun and learning aspect of it but for now my simple home automation project is saved from unneccesary frustration.
Of course disconnecting the PIN loses USB flashing capabilities but I made sure that it is reversible if I ever need to re-flash manually via USB. Just as a word of caution at this point. Other options are better in that regard but I like the ease of use in this case.
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Thanks a lot, now it works perfectly
FWIW I found exactly the same issue with four esp-wroom-32 devices I purchased off Aliexpress recently. Incredibly awful WiFi - intermittent ranging from bad to non-existent. If I bypassed the usb-c socket and powered it directly, it was fine. As it was only a handful, rather than lifting some pins and running tiny bits of wire, I did this instead:
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This info is life-changing. I thought i was going crazy and couldnāt understand why I couldnāt connect.
Hi is there a recommendation for a cheap ESP323 version with good wifi signal range?
I read the ESP32-WROOM-32D with antenna going over the PCB should work good, but I do not have any proof.
Had big probems with ESP32ās not wanting to connect to wifi with Esprensense. Either not at all or after the first reboot. recently purchased five ESp32ās with 2102 converter instead of ch340 and they all worked out of the box.
Thanks to all for the information shared here; this finally solved my issue with 5 devices lying around here. Also a new one that Iāve ordered from another seller, but with the same issue.
After a bit of further investigation, hereās some information Iād like to share:
- According to the datasheet, the ESP32 is not 5V-tolerant on any I/O pin
- However, in practice, it somehow seems to be
- Espressiv confirms this, but also takes no guarantee whatsoever (see below)
Agreed. If you want our official stance, itās that we do not support 5V inputs period, please keep to the values pointed out in the datasheet, donāt go guessing to the internal structure as the main problem wrt 5V-compatibility is things that are very hard to put in a schematic (iirc degradation due to quantum tunneling, for instance).
Weāre happy to help you wrt unofficially getting something to work, but do know that anything in that direction is out of spec and we cannot guarantee the long-term stability of a solution like that.
My conclusion: It seems plausible there may be some side effect to the Wifi, e.g. some current flowing into the RX pin is going through the chip, disturbing working points in the Wifi analog circuits.
From now on, I will use 3.3V on all ESP32 I/Os, period. Seems easier than spending more hours searching for strange side effects. Or even mid-/long-term failuresā¦
Edit:
For this specific board, powering the CH340 from 3.3V seems to be the proper fix. Only drawback should be the CH340 consuming power even when USB is not connected. Hopefully it will go into āUSB suspendā mode then, where it should consume 0.15mA max.
Alternatively, powering the board from Vin if the USB/serial function is not needed will also do the trick (as pointed out by others earlier), as the CH340 will receive no supply voltage then.
hi guys, I just registered here to thank you. Was hustling 2 days (well, evenings) with those pesky ch340s, sometimes the wlan worked, then it was out again, tried everything I could think of.
Saw this thread here, cut the pin, and immediately it worked!
Thanks again!
A word of warning. I was happy to find this topic, but I destroyed two of my ESP-WROOM-32 HW-394 boards. I did the USB-power to VIN/GND thing. I literally smelled something was not right. The boards got very hot and didnāt work anymore. I tried a different board with a different USB adapter, same story. Turns out the USB cable I cut open had black attached to +5 and red attached to GND. You canāt trust color codes, always verify with a multi meter.
My ESP32 board looks a lot like all of your pictures, but with two distinct differences:
- HW-394 written on the board.
- One extra resistor (?) on the board.
I cannot find GND where @Crypter found it; for me it is the capacitor closest to the USB port. Havenāt tried the hack yet. Just happy I got the USB trick to work.