ESP8266 Community Forum

- Tue Mar 10, 2015 10:39 pm #11762 Hi
I have been using an esp-01 and esp-12 without level shifting the serial communication without any issues so far. I know its best practise to as the esp operates at 3.3v but so far my modules are handling it no problems.

Has anyone experienced problems with communicating with a 5v device without level shifting? I am wondering if during communication parts of the chip are heating up and will eventually fail.

I might setup a continuous data feed to the esp to see what happens over 12,24 hrs maybe a week straight?

- Wed Mar 11, 2015 2:17 am #11769 Use a level shifter. Some 3.3v devices have 5v tolerant pins but tolerant often doesn't mean robust and any variation over 5v can mean the pin gets blown.

- Wed Mar 11, 2015 6:50 am #11782 yeah yeah ive read it 100x on here use level shifting. but have you personally experienced a blown pin?

- Wed Mar 11, 2015 9:08 am #11792 Hi
The reason you may not have had problems is that the voltage from the serial device may not be 5V!.
I recently connected a 5V serial device to my esp without problem, but when I measured the output voltage on an oscilloscope it was only 3.6V which the esp could easily handled.

Gerry