ESP8266 Voltage Regulator (LiPo and Li-ion Batteries)

In this guide, you’re going to build a voltage regulator for the ESP8266 that can be used with LiPo and Li-ion batteries.

Watch the video version

This guide is available in video format (watch below) and in written format (continue reading this page).

ESP8266 power consumption

The ESP8266 is well known for being power hungry when performing Wi-Fi tasks. It can consume from 50mA to 170mA. So, for a lot of applications it’s not ideal to use a battery with it.

It is better to use a power adapter connected to mains voltage, so that you don’t have to worry about power consumption or charging batteries.

ESP8266 with LiPo/Li-ion batteries

However, for some ESP8266 projects that use Deep Sleep or don’t require constant Wi-Fi connection, using the ESP8266 with rechargeable LiPo batteries is a great solution.

For battery powered applications the ESP-01 version is the recommended board, because it has few on board components.

Boards like the ESP-12 NodeMCU use more power, because they have extra components like resistors, capacitors, chips, etc..

Since LiPo batteries are so easily available, I’ll show you how to power the ESP8266 using those types of batteries.

This guide is not about different types of batteries and I won’t explain how LiPo batteries work. I’ll just give you the relevant information to complete the circuit presented…

LiPo/Li-ion batteries fully charged

LiPo/Li-ion batteries are rechargeable with the appropriate charger and they output approximately 4.2V when are fully charged.

However, as the battery keeps discharging the voltage starts to drop:

The ESP recommended operating voltage is 3.3V, but it can operate with voltages between 3V and 3.6V. So you can’t plug the LiPo battery directly to an ESP8266, you’ll need a voltage regulator.

Typical Linear Voltage Regulator

Using a typical linear voltage regulator to drop the voltage from 4.2V to 3.3V isn’t a good idea.

For example: if the battery discharges to 3.7V, your voltage regulator would stop working, because it has a high cutoff voltage.

Low-dropout or LDO Regulator

To drop the voltage efficiently with batteries, you need to use low-dropout regulator or also known as LDO regulator that can regulate the output voltage.

Having a low dropout voltage means that even if the battery is only outputting 3.4V it would still work. Keep in mind that you should never empty the LiPo battery completely, because it will damage the battery or decrease its lifetime.

After researching LDOs, I found a couple of good alternatives. One of the best LDOs I’ve found was the MCP1700-3302E.

It’s fairly small and It looks like a transistor.

There is also a good alternative like the HT7333-A.

Any LDO that has similar specifications to the ones shown on the datasheet below are also good alternatives. Your LDO should have similar specs when it comes to:

  • Output voltage (3.3V)
  • Quiescent current (~1.6uA)
  • Output current (~250mA)
  • Low-dropout voltage (~178mV)

MCP1700-3302E Pinout

Here’s the MCP1700-3302E pinout. It has GND, Vin and Vout:

Other LDOs should have the same pinout, but you should always search for your LDO’s datasheet to verify its pinout.

ESP8266 Circuit with LDO and Li-ion Battery

Here’s the parts required to design the voltage regulator for the ESP-01:

You can use the preceding links or go directly to to find all the parts for your projects at the best price!

Take a look at the diagram below to design your own voltage regulator circuit.

Or you can take a look at the Fritzing diagram (the ceramic capacitor and electrolytic capacitor are in parallel with GND and Vout of the LDO):

The pushbutton is connected to the RESET pin of the ESP-01, for this particular guide it’s not necessary, but it will be useful in a future guide.

Here’s the final circuit:

About the capacitors

The LDOs should have a ceramic capacitor and an electrolytic capacitor connected in parallel to GND and Vout to smooth the voltages peaks. The capacitors prevent unexpected resets or unstable behaviour for your ESP8266.


Let’s power the circuit and test it. Having the multimeter measuring the Vin voltage of the LiPo battery, you can see it outputs approximately 4.2V, because the battery is currently fully charged.

Let’s place the multimeter probe on Vout. Now, the multimeter is measuring approximately 3.3V which is the recommended voltage to power the ESP8266.

Voltage regulator

A popular voltage regulator design for the ESP8266 looks like this:

You solder the capacitors to the LDO, so in the end you have a voltage regulator in a small form factor that can be easily used in your projects.

I hope this guide was useful. This concept will be very helpful to power future projects.

This is an excerpt from my Home Automation using ESP8266 eBook. If you like ESP8266 and you want to learn more about it. I recommend downloading my course: Home Automation using ESP8266.

I hope this guide was useful. Thanks for reading!

Learn how to program and build projects with the ESP32 and ESP8266 using MicroPython firmware DOWNLOAD »

Learn how to program and build projects with the ESP32 and ESP8266 using MicroPython firmware DOWNLOAD »

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21 thoughts on “ESP8266 Voltage Regulator (LiPo and Li-ion Batteries)”

  1. Hello.
    Thank you for this manual. I used this circuit to power my ESP32 project with the 18650 Li-Ion 4.2V battery. It works fine until battery voltage drops to 3.5V. Then LDO regulator gives only 2.8V and lower and ESP32 is dead. Do you now about some other circuit, which can gives still 3.3V, when battery voltage is between 4.2 to 3.3V?
    Thank you.

    • Forse puoi collegare 2 batterie in serie ed ottenere così una tensione più alta, ma bisogna usare 2 batterie identiche, e verificare che il regolatore accetta tensioni di ingresso anche di 8,4 volt.

    • Forgive me my late reply but maybe something isn’t right. If you are using the HT7333 that only has a 90mv drop. Admitted, that is at 40mA and the ESP can draw quite a bit more, but i doubt the 7333 would go up to 700mV drop.
      Can it be that you have peripherals attached that would drive the power consumption above 250mA causing the 7333 to collapse?
      Anyway, as it is almost a year ago, I hope you found an answer

      • if you used the MCP that has a slightly larger voltage drop (170mV) and that is still a far cry from what you experienced. The MCP1700 does shut down though when >250mA is drawn

    • Hi Vit,

      I’m sure you’ve already solved this problem but I’ll post this in case someone else is interested. Here’s most likely why the voltage drops when the battery voltage is 3.5 V.

      From the MCP1700 datasheet:

      See the Vin parameter in the DC Characteristics table. See Note 1.
      1:The minimum VIN must meet two conditions: VIN >= 2.3V and VIN >= VR+3.0% + VDROPOUT.

      VIN is the battery voltage
      VR is the nominal regulator output voltage-in your case 3.3V
      Note from the data sheet that VDROPOUT typical = 178 mV and VDROPOUT maximum is 350 mV.

      With the typical VDROPOUT of 178 mV, VIN = (VR * 1.03) + .178 = 3.577 V i.e., greater then 3.5 V
      With the worst case VDROPOUT of 350 mV, VIN = 3.749 V i.e., greater than 3.5 V

  2. Hi Sara & Rui,

    Brilliant tutorial.
    I am trying to create a voltage regulator for the ESP-12 NodeMCU connected to a NEO-6M GPS module. The goal is to acquire real-time GPS data as a wearable.

    Will the same parts required to design the voltage regulator for the ESP-01 work for the NodeMCU?


  3. Hi,
    I am trying to build a fritzing diagram including the MCP1700-3302E but cannot find this part online. The included voltage regulator has the wrong pin-out in the PCB. Is there any chance to get the version you created?

    Kind regards


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