ESP8266 Community Forum

- Tue Nov 01, 2016 10:52 am #57496 Given that there are no recent official notes on the matter and that the internet is full of anecdotal evidence that the chip MAY be 5V tolerant, here is the question:

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Has any of you ever fried a ESP8266 by applying 3v3 to Vcc and 5V TO THE DIGITAL PINS (Rx and GPIO)?
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Please don't post opinions or links to different versions of the datasheet, only personal experience of damaging the chip this way.

- Fri Nov 04, 2016 8:41 am #57640 I use an ESP12 and also an ESP01 in conjunction with Atmega devices. The Atmega ist operating @5V, the ESP @3.3V and I have an I2C link between ESP and Atmega with no level-shifters without any problems since 9 month. The I2C pullup are connected to 3.3v which is sufficient for the Atmega.

- Fri Nov 04, 2016 9:09 am #57641 I2C are driven with OpenDrain outputs, it is the PullUps that bring the lines to HIGH, therefore it is not a case where 5V tolerance is involved.

- Fri Nov 04, 2016 12:12 pm #57661

Given that there are no recent official notes on the matter...

Actually there are recent official notes. On page 21 of the November 27, 2016 FAQ
https://espressif.com/sites/default/fil ... faq_en.pdf

Are the GPIO pins 5v compatible?

No, they are not. While many applications may get away by using resistor voltage divider or series resistor, we highly recommend using a proper logic level converter chip to interface with 5v logic. Not doing so may lead to damage to the ESP8266 in the long run.

Official statement but this being the internet, believe what you want.