Often when working with micro controllers 5V are needed. The ESP-01 however uses 3.3V and thus can't simply be connected to an Arduino or most USB/TTL convertes.

To fix this, I created this simple 5V breakout board for your ESP-01.

Step 1: The Basics

For the circuit you need the following parts:

  • 1x low drop voltage regulator (I used a LF33 CDT)
  • 1x 10µF capacitor
  • 1x 100µF capacitor
  • 1x 1k resistor
  • 1x 1.8k resistor
  • 1x 2 pin header (male) and jumper
  • 1x 2x4 header connector (female - for the ESP-01)
  • 1x 4 pin header connector (male or female)
  • 1x piece of perfboard

The circuit is quite simple. The voltage regulator supplies the 3.3V to supply the ESP-01. The two capacitors are used to smooth the input and output voltages. Instead of the LF33 you could also use a cheaper LT1117 or similar. Refer to your data sheet for the correct capacities needed for those.

The TX from the ESP-01 can be wired straight through, because an Arduino or a USB/TTL adapter can work with the 3.3V input.

The ESP-01 RX however should NOT be directly connected to a 5V TX. For this we build a simple voltage divider with the two resistors.

The jumper connects GPIO0 to ground. This is used to enter the programming mode of the ESP.

Step 2: Soldering

Because the LF33 I ordered are on chip and not through-hole I first soldered small wires to it. This makes it easier to solder it to the perfboard.

Then solder everything to the perfboard. My soldering work is not the best so don't take it as an example ;-)

Step 3: Testing

Before you connect your ESP-01 you probably want to test your new breakout board. For this I use a basic 5V power supply. To measure the voltage I put a small cable into the VCC pin of the ESP-01's connector. Measure between the cable and any ground connector.

3.3V -- it works!

Step 4: Going Live

Now we will connect everything to the board. For this you should disconnect your power supply!

Just put the ESP-01 into the two-rowed connector. To communicate with the ESP I also connected a USB/TTL converter. Remember to cross connect the pins:


UART TX to ESP RX (where the voltage divider is)

You should also connect the converter's ground to the board's ground (the yellow cable)

Alright. Connect your USB/TTL to your computer and plug in the power supply. If the jumper is in place, the ESP is in programming mode and you can flash programs onto it (there are other instructables available for this).

If you remove the jumper and reset the power you should be able to connect the ESP to your serial monitor. Check your baud rate if you can't see anything or just scrambled characters.

And that's it. You can now use your ESP-01 with 5V and for example, connect it to an Ardunio.

<p>great job. </p><p>say, if i use 9v power jack, i need to put other capacitors and resistors?</p><p>is there any benefit from using 9v instead of usb 5v?</p>
<p>Basically if you only want to power it, you could provide 9V input. But it depends on the voltage regulator (take a look at its data sheet). The LF33 CDT can take up top 16V input.</p><p>However I would NOT use a simple voltage divider (the resistors) for the RX pin. Which device would even use a 9V serial connection? If thats your goal you should use a logic level converter. Something like this but for higher voltage: https://learn.sparkfun.com/tutorials/bi-directional-logic-level-converter-hookup-guide</p>
<p>Very well done! Thanks for sharing!</p>
<p>Cool homemade breakout board! Thanks for sharing! </p>

About This Instructable




More by Mat_F:Simple 5V breakout board for ESP-01 (ESP8622) 
Add instructable to: