Powering ESP8266 from Leonardo's 3.3v pin

Question

I'm new to Arduino, and I'm trying to connect my Leonardo via WiFi using a ESP8266 module. What I want to know is if I can power it directly from the onboard 3.3V pin like in the image:

Leonardo

Or do I need an external voltage regulator? I don't want to damage it. Thanks!

Answer 1

The Leonardo is specified to provide only 50mA on the 3V3 pin. A ESP8266 can use up to almost 300mA when transmitting. Consider using a LDO regulator connected to the 5V pin instead.

• Ignacio Vazquez-Abrams: If supplying power via USB it should be fine unless you have a few other devices connected to it. If supplying power via an external 7-12V supply then the on-board regulator may get a bit warm, so you'll have to judge from that.
• Majenko: That specification in wrong. The 3.3v regulator is actually 150mA not 50mA. Don't believe everything you read on the Arduino website.
• Christian Rodriguez: Ok, so which one should I trust? I don't want to find out by testing and killing my brand new Leonardo ;)
• Ignacio Vazquez-Abrams: If you're communicating with the ESP8266 for very short bursts then you may be able to get away with the on-board LP2985 if you add a local bulk capacitor. If you need constant communications then you should strongly consider a larger regulator.
• Christian Rodriguez: Ok, I finally used an LM2596 to lower the voltage from the 5V pin to 3.3V and a voltage divisor for the Rx pin in the ESP8266 module.

Answer 2

Remeber sometimes Arduino board is not delivering sufficient voltage to the ESP8266 module. You can use a 3.3 V ( Do not exceed input voltage from 3.3v) regulator ( AMS1117 ) to power this module.

• Christian Rodriguez: Actually that's the one I've been using. Aaand, I got rid of the Leonardo. I'm programing the ESP module, avoiding the bottleneck of the slower Leonardo's processor.