If possible, I'd like to run the Waveshare 4.3 e-paper display and a Nano or Micro off of batteries. In my application, the screen would be refreshed once every five or ten minutes; in between, it would be powered off or sleeping, whichever uses less energy (starting up after power off might use more than waking from sleep).
The Waveshare website and wiki don't seem to have much information about the 4.3 e-paper power supply requirements or current demand. They say try a 5v supply if 3.3v doesn't work (!) and that the "sleep" current is about 5 mA. I haven't found anything more on the web.
Anyone have better information on power consumption during a refresh, start-up, wake from sleep, etc?
This is not so easy to measure. My Keweisy USB meter seems not sensitive enough. Would have been helpful for cumulated mAh.
On my Voltmeter I saw up to 150mA on startup, ~45mA on steady state, ~100mA on updates, and 3.5mA in stop mode. So maybe you would need to cut off supply during idle time for battery operation.
Do you need the resolution of this display, or the grey levels?
The Waveshare 4.2 300x400 b/w SPI e-paper display may be better suited for battery operation.
My personal impression is the 4.2 inch display (Good Display GDEW042T2) has better contrast and contrast stability compared to the 4.3 inch display.
I use it with Wemos D1 mini using deep sleep mode during idle time, e.g. with 18650 Li Accu.
Thanks very much for the reply and data! Much appreciated. +1
I picked this one just because it appeared to me that it is the only e-paper display that the Arduino community (mostly you!) has much experience with.
I probably don't need its resolution - 300x400 would probably be ok. I will be drawing a line graph of temp and humidity history, and showing the current values with numbers.
PS: I just found the forum topic on the Good Displays - thank you for all your work on that.