What is the voltage output range of the ESP32

[Hasan Shadi]

I am trying to know what is the voltage output range for the ESP32, using the GPIO library, and setting the level as high, I got 2.8V. But, using UART for example on pins 9 & 10. I have detected nearly 3.3V or above (they are internally connected to the flash memory), can you tell me the voltage output range, and when can it give more than 3V?

That is because I need to interface the EPS32 with another boards that has a logic of 5V, like the Arduino Uno and some GSMs, like the SIM800L and the SIM800C. I could use a logic level shifter, but still I need to know the possible voltage ranges. And because the signal has to be more than 3V for other electronic parts (that has 5V logic) to detect the signal as high, not low.

[Sprite]

In general, things like that are in the datasheet of the chip in question, and for the ESP32, it's no different: the datasheet lists it on page 36, under "DC Characteristics".

[miltoneo]

This is an old issue but here we go.

I had the same issue when considering 3.3v as default output for any gpio but measuring 2.8v as real output.
So I went to the datasheet https://www.espressif.com/sites/default ... et_en.pdf and got that output voltage (VOH) is defined as VOH(min) =0.8×VCC ou VOH(min)=VCC−0.4V.

So, 2.8v as VOH is complying with the datasheet and I had to change my resistor.

[MicroController]

Note that the voltages at an output pin depend on the current that pin has to source/sink. Specifically, you'll get 3.3V high/0V low output only when you have no (resistive) load on the pin, i.e. when it is connected to a high-impedance input. When you're pushing tens of mA through the output you will 'feel' the output's impedance and never reach 3.3 or 0V.