How does the NanoESP32 receive power?

Official Hardware Education Alvik
1

I'm looking to get a better understanding on how the power supply of the Alvik works, specifically how the NanoESP32 is powered when the Alvik is running off the battery:

Does the NanoESP32 receive power on its VIN pin or 3.3V pin when plugged into the header sockets of the Alvik?

On pg 11 of the Alvik datasheet, it shows that 3.3V and 5V power sources are created from the battery:

Screenshot 2025-09-09 at 10.27.56 PM
Screenshot 2025-09-09 at 10.27.56 PM1628×614 91.1 KB

The NanoESP32 datasheet recommends that if being powered on its VIN pin, that it recieves 6-21V.

Since the power system only creates 5V or 3.3V, and 5V is under the minium recommendation for the VIN pin, does it mean that the NanoESP32 recieves power on its 3.3V pin?

2

Not necessarily. Take some time and research Boost, Buck, and SEPIC converters, the answer should become obvious.

3

Thanks. Yes, I’ve researched these and have implemented in some test circuits, but I’m still failing to understand how the NanoESP32 is receiving power on the Alvik.

4

From the user manual:

To power the Nano ESP32 you may either use a USB-C® cable, or the VIN pin. When using the VIN pin, use voltages within the range of 5-18 V as the MP2322GQH converter on the board may otherwise be damaged.

Then two sentences later they say:

The recommended input voltage on the VIN pin is 6-21 V.

Then in the datasheet they provide this additional information

The efficiency of the converter depends on the input voltage via the VIN pin. See the average below for a board operation with normal current consumption:

  • 4.5 V - >90%.
  • 12 V - 85-90%
  • 18 V - <85%
5

This is why i’m confused. Outside of that one sentence you highlighted above, all the recommendations on the product page and datasheet say to use 6V or greater on the VIN pin to power the NanoESP32.

So if the Alvik is only boosting up to 5V, it is either

  1. Powering the NanoESP32 with 5V on the VIN, against their own recommended minimum voltage
  2. Powering the NanoESP32 with 3.3V on the 3.3V pin

I’m trying to figure out which one it is

6

Do you have a multimeter?
If so you could try measuring the voltages on the VIN pin and the 3.3V pin.

If powered by the 3.3V pin, then there would be no voltage on the VIN pin.

7

Just measure the voltage on Vin and you will know. Be very careful when you do it.

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