drsrikanthb wrote:I need to interface my ESP2 to other 5V CMOS inputs. I need to know if ESP IO pins are TTL compatible or CMOS compatible. I believe that if they are TTL level outputs my 5V logic would be able to correctly work without level conversion as I am using ESP for outputs only and not inputs. But if ESP outputs as CMOS logic I may need level conversion for outputs too
Hello!
Looks like nobody have answered yet, so I decided to do so.
As far as I know, they are TTL compatible. I have a couple of 5V LEDs (similar to Neopixels), that are actually 5V controlled, but work completely fine with my ESP32 connected directly (ESP only outputs), without a level converter.
The maximum voltage you can get out of a pin is about 3.3V, but make sure you don't load them with lot of current. By average you can get 3.2V out most of the times.
There are level converters online that you can check, for very very veeeeery cheap.
The only thing before using the ESP in this way is to check the datasheet of the device you connect it to, and see what the input of the device is like and what are the startup conditions, so you make sure that 5V never reaches the ESP.
Vader[BEN]