Thank you for the information. It should then be safe if the oled’s supply voltage be fed from the 5v arduino micro/pro micro’s onboard 3.3v regulated output? What about the signal logic lines from the arduino to the oled?
I use the 3.3V output from the Arduino Micro to drive the display on my system. A 5V Sparkfun micro doesn’t have a 3.3V output.
For the signals, I use a level converter module
EDIT, Correction: My display has an on board 3.3V regulator, so I power it with 5V. I use the 3.3V from the Arduino Micro for the low side of the level converter module.
Thank you for the explanation, I understand now. I had thought the pro micro’s vcc pin was the same as the 3.3v regulated output pin of the micro, but you’re right that it isn’t, if powered via USB it will output 5v.
Thank you for taking the time explain it to me.
Where I can purchase a proper display?