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Powering ESP8266 from Arduino 5V using LM317T

PostPosted: Tue Mar 17, 2015 7:52 am
by Lucian Marica
Hello,

Arduino specifications state that 3.3V out can only deliver 50mA, lower than ESP module needs at peaks. I am wondering if it is possible to power ESP from the 5V on the arduino, using a LM317T regulator.

I plan to use it like in this schematic:

Image

Re: Powering ESP8266 from Arduino 5V using LM317T

PostPosted: Tue Mar 17, 2015 6:08 pm
by wooduino.ca
While this may work, the question is how you plan to power the Arduino. If it is from an external power supply, not a problem (although the current drawn by the ESP can get into the 200mA range at times). If, however, it is from the 5V from the USB interface, you may have a problem.

Re: Powering ESP8266 from Arduino 5V using LM317T

PostPosted: Fri Mar 20, 2015 1:06 am
by Aonko
The 5v pin on an arduino can only source 200ma. It would be better to source from an external power supply. It probably would work but I don't think your arduino would survive long term.

Re: Powering ESP8266 from Arduino 5V using LM317T

PostPosted: Fri Mar 20, 2015 8:24 am
by pete_l
The ADJ pin of the LM317T does not appear to be connected to anything.