Wireless charging for XIAO esp32 c3 based projects

I’m working on a XIAO ESP32 C3 based project which uses 3.7V 300 mAH lipo battery. I want to add wireless charging to the project.

How should I wire the QI charging receiver module with esp32?

  1. Should I connect the battery and also the QI charger receiver module with charging pads located below the esp32 c3?

  2. Or Should I connect the battey with the charging pads of esp32 and the QI receiver with the 5V input pin of the esp32c3?

I’m using this QI receiver Module

Hi there,
At first glance… I would connect it thru the USB-c port, and solder the battery to the Pads.
but YMMV.
GL :slight_smile: PJ

Hello. Have you found a way to connect it? I also want to do the same thing on my ESP32S3. According to the documentation, I believe I should connect the wireless charger to the 5V and GND pins, and also add a diode between the charger and the 5V pin.

Power Pins

  • 5V - This is 5v out from the USB port. You can also use this as a voltage input but you must have some sort of diode (schottky, signal, power) between your external power source and this pin with anode to battery, cathode to 5V pin.
  • 3V3 - This is the regulated output from the onboard regulator. You can draw 700mA
  • GND - Power/data/signal ground

I haven’t tested it myself yet, so please let me know if you have any relevant advice.

Hi there,
check it out. This is working.

instead of the phone in the picture just plug in a xiao with a battery soldered to it’s battery pads and BoB’s your Uncle.
GL :slight_smile: PJ

I need to leave the Type-C port for another purpose, so I can only connect the wireless charger’s receiver to the pins.

Hi there,
I see, Well If it’s just for the serial port of it, you could use the 2nd serial port unless those are being utilized. If you use the 5V pin the diode is a MUST. and not to plug a real USB-C device into it at the same time that’s powered anyway. You already know this.
GL :slight_smile: PJ

Actually I’m really curious about what would happen if I plug USB in while wireless charger is also charging. It looks like there is already a diode on board between USB 5V and chips. Anyway, I will follow your suggestion. I wouldn’t risk my board to do that, unless someone can confirm that’s safe.