Waveshare 1.54 inch ePaper display requires 5Vs from Arduino Uno I have an Arduino Uno and I would like to attach a Waveshare 1.54“ display (red, black &amp; white) to it.

All the specs tell me that it consumes 3.3 V which I have readily available on the Arduino Uno.

I could not get the display to work until I attached the Power pin to 5V instead of 3.3V.

I did try this with two different ePaper displays and the situation was the same. 

I also tried to power the display with a Raspberry Pi‘s 3.3V (with the GNDs connected). But this did not work either.

So I am wondering what I am missing here, is it simply a power issue and my Arduino can‘t deliver the necessary current?
The answer lies in the FAQ for that display:


  Why the e-Paper cant work with Arduino?
  
  Answer:
  
  The I/O level of Arduino is 5V, and the e-Paper should be driven with 3V3. If your Arduino cant drive the e-Paper successfully, please try to convert the level to 3.3V
  
  You can also try to connect the Vcc pin to the 5V of Arduino to see whether the e-Paper works, but we recommend you not to use 5V for a long time.


So while you can run it from 5V, you really shouldn't, since you run the risk of breaking it.  

Instead, you should employ proper logic level shifting to reduce the Arduino's outgoing signals to 3.3V and, more importantly, boost the incoming signals from the display to 5V.