ESP32-S2 (Wemos S2 Mini) - Powering issues 5V VBUS pin

Other Hardware Motors, Mechanics, Power and CNC
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Hi, I am having some issues regarding a Wemos S2 Mini/Lolin S2 mini.

I am trying to power it via the VBUS pin with 5V but it seems bug out when I try to use 2.4ghz wifi via ESP Now.

I have tried, and successfully so, to power it with a with a dc-dc step up converter that goes to 1 AAA battery (sure, its only rated to provide about 100mA of power with an input of 1.5v) with only blinking the onboard LED on pin 15. Whenever I try to use my TX or RX code it will simply not work. It keeps restarting so this tells me it does not provide enough current. I can wrap my mind around the fact that this is due to the limited mA the converter provides.

But then I tried to hook it up to another dc-dc step down converter (MINI 360) to 4 AA batteries (6V) in series. This converter makes it 5V and is rated for 1.5A (3A max) output. And it still does not give enough power for the Wemos S2 mini to function correctly, it still keeps restarting. This confuses me because I have read online that people have successfully powered a normal ESP32 chip with only 2 AA batteries directly to the 3v3 pin, so a AA battery should be able to provided enough current.

I am still going to experiment a little bit when I have some more free time, but I was wondering if anyone else has this issue and has a fix for this.

Could I possible postpone the ESP Now init, delay by a few seconds after turn on?, to do make it work or can I limit the processor speed to not draw as much current but still remain functionality I want it to do?

For anyone wondering, the TX is reading Roll and Pitch from an IMU and reads two potentiometers. The RX receives this converted data and writes it to a few servos. The code and chips work perfectly fine when using a powerbank or the usb ports in my computer.

I would like this to work, as in the context of a conventional TX RX where the RX is powered by a normal buck 5v e.g. that you can plug into an RC car, airplane, you name it.

TLDR:
I have trouble providing enough current to ESP32 S2 (Wemos s2 mini) to make it work with ESP Now for a TX RX system. In what ways can this issue be solved? Hardware (dc-dc buck with maybe a capacitor?) or software (limiting processor speed or delaying ESP Now init?).

I am actually relatively new to Arduino, ESP32/microcontrollers and coding in general so perhaps I don't see the obvious, my apologies in advance.

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What does the specs of the Wemos tell?
What is the powering of the Wemos S2 Mini/Lolin S2 mini.? Schematics could be helpful.

100 mW and 5 volt? That spells 20 mA. Sounds way too low.

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The schematic of Wemos S2 Mini: https://www.wemos.cc/en/latest/_static/files/sch_s2_mini_v1.0.0.pdf
I believe it is 5V only via VBUS but could be wrong, I am not really good at reading schematics (I am a beginner)

My bad, it is 100mA not mw. This worked fine for just powering it on and blinking the inbuilt LED on pin 15 but to low for any wifi activity or running the TX and RX code.

Shouldn't it work though with the 4xAA batterie in series with the MINI 360 (5V, 1,5A) connected to the VBUS and ground or am I missing something?

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I am not sure about a Wemos 32, but for a Wemos 8266 it can't work because the current draw when Wifi is transmitting or receiving is 200 mA. I would assume the Wemos 32 works more or less the same.

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ESP32 mini S2 had this problem (still has on some boards from ebay/amazon).
The issue was restarting evey 1 second or so when using WiFi (broadcast a wifi network).

Solution from other forums: One capacitor on boards is not soldered right to GND.
Some newer boards are working fine. See below.
I tried to solder a blob of solder a 1/4 inch wire to EN pin on board (also tried 1 inch coiled wire), and it helped, esp32 is not resetting itself anymore and works fine.

Bad module was from amazon, good from Aliexpress (12.2023 order).

esp32 reboot issue
esp32 reboot issue1128×813 166 KB

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I also bought one of these boards.
Did you already verify whether using 5v on the vbus pin is the right thing to do or whether it should've been 3.3v?

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Vbus can handle 2-6volt. Maybe a little more but the datasheets state 2-6. Wemos esp32 s2 mini uses this LDO; ME6211C33.

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