How to Power an Arduino ESP32 with a 3.7V Lithium Battery (Quick Tips)

In this video I show how to power an Arduino ESP32 board using a 3.7V lithium ion or lithium polymer battery. I walk through the wiring setup using the VIN pin, explain how the onboard AMS1117 voltage regulator is supposed to step the battery voltage down to a stable 3.3V, and cover what actually happens when the input voltage is too low for proper regulation.

I also explain a common issue when using a single cell Li-ion battery with the ESP32, where voltage readings and ADC measurements can become inaccurate due to regulator dropout. In this case, the AMS1117 does not maintain proper regulation when the input voltage is close to the output requirement, which can lead to incorrect battery monitoring results.

Finally, I show a practical fix using a boost converter to provide a stable input voltage, improving system reliability and allowing accurate voltage readings through a voltage divider. If you are trying to run an ESP32 or Arduino board on a lithium battery, this video will help you understand the correct power setup and avoid my mistakes.

00:00 Intro
00:10 USB Battery Bank Replacement
00:20 3.7v Lithium Battery
00:28 ESP32 Vin
00:50 Voltage Reading Issue
00:58 Over discharge
01:07 Voltage Divider
01:35 AMS1117 Dropout Voltage
02:02 5v Boost Converter
02:57 Summary

Credit:
Music by: CreatorMix.com

Видео How to Power an Arduino ESP32 with a 3.7V Lithium Battery (Quick Tips) канала Theory to Thing