ESP8266 Community Forum

Paulo Filho wrote:Hello friends.

I'm looking for this information but i can't see in datasheet. I have a font with output 3.6v. My doubt is the ESP8266 can be supplied with 3.6V?

Thanks

Best Regards.

Paulo

Yes you can supply 3.6v and this is the max.

Hi there, I have used 2.9v to 3.9v(dependant on input V) on the Environment Sensing devices I have in use, I am also using "primitive" regulation method using 1n4001 to supply the ESP I am logging voltages as low as 2.8 and still running.
I messed about with an old Serial Console for a PDP (DEC VT) at the start of the year and posted a piece of text with the outcome of this....

https://github.com/genguskahn/ESP8266-F ... LEVELS.txt

So as long as it starts with a 3 this is perfectly fine some of my devices have been running Constantly since March(Esp-01 512KB).....

I have been programming mine while going direct off a LiPo battery (nominal 3.7v but in reality 4.2volts when fully charged) never had a problem.

I recall seeing one reference in the deep dark bowels of the datasheets that the die is up to 6v MAX tolerant but that was not consistent with all the other documentation so I thought it was a typo. That said, I have NEVER fried one and I have even had them running off 5v myself (dodgy, el-cheapo 5v-3.3v step-down converter was just letting it through as-is).

I still run them in production with a regulated 3v3 suply but I have even found that the I/O (on RX and TX) to be long term 5v tolerant on old ESP-01 connected directly to an Arduino Nano v3 compatible.

I have re-checked the datasheets.

Although there is apparently a 6v over-voltage reset mechanism (like a circuit breaker) on each IO pin the supply must not go over 3.6-3.9 v. It is not the die but the pins that have this protection (please don't quote me on that) which explains why my (and plenty of others) have not fried my modules while communicating direcltly with 5v Arduinos (UNOs and Nanos) but doesn't explain why I haven't fried one by accidentally applying 5v supply.