ESP8266-01 power supply

Other Hardware General Electronics
1

Hello,
a few weeks ago I bought an ESP8266-01 module. I tested it and it worked great. I even managed to upload some temperature readings to freeboard.com but the problem is I used the 3.3V from the Arduino and I noticed the module is overheating. I read it's better to use a seperate power source so I tried to use a 5V battery with a simple voltage divider but the module didn't even turn on. So I went back to trying to power it from the Arduino's 5V, using the voltage divider, as seen on the attached pictures, but to no avail. Can someone please tell me what I'm doing wrong?
Thanks in advance!
P.S. I tested the module later, powering it from the 3.3V again, it still works. I'm using an Arduino Uno.

schematic.PNG

fritz.PNG

2

You need to use a 3.3 V regulator not a resistive divider. That unit draws about 200 mA when transmitting which your circuit cannot supply.

Russell

3

You can't use a voltage divider if the thing you're providing the voltage to is drawing current. That's only for signals and reference voltages.

The moment the ESP tries to draw any current, the voltage drop across the resistors skyrockets and it's no longer got any power.

You need a voltage regulator.

4

Great, thanks! I'll look for those then :slight_smile:

5

tvrtko:
the problem is I used the 3.3V from the Arduino and I noticed the module is overheating.

Which module is overheating?

Do you mean the regulator on the Arduino? That might overheat because the ESP8266 draws too much current. If however it is the ESP8266 that is overheating, that is not going to be from the 3.3V power supply unless that power supply is producing grossly more than 3.3V. If the 3.3V is indeed 3.3V and the ESP8266 overheats, you have done something really wrong!

Hint - put a 470μF capacitor on the 3.3V.

6

I failed to mention I was using using serial to communicate with the ESP. I connected Arduino's TX to the ESP's RX, and vice versa. After reading some stuff I realize now that's where I should have used the voltage divider and I would assume that's causing the ESP to overheat.