It is quite easy to display any kind of indicator about power state on screen, small (or large) icon, text, etc...

This device has an ePaper display which reflects the light and is readable similarly to the ordinary paper. You will be able to read it in the lighting conditions in which you can read the paper book.
Just turn the light on.
Some (rare) ePaper displays have the frontlight module on top of the display, like this one, but M5Paper does not have such a module.

In case of ESP32 you can measure power consumption with practically any multimeter in uA range.
If the current is < 5-10 uA you have an excelent low power device.
You will rarely need the information about power consumption in sub uA range and investing any amount in a device for measuring current of ESP32 deep sleep mode is probably waste of money (unless you need it for other measurements, of course).

I think it could be also usefull to make available some IT8951 documentation. It is hard to find and could be very usefull for developers.

Data sheet
USB Programming Guide, also relevant for SPI programming.
SPI Programming Guide

Display panel (ED047TC1) data sheet

@zontex said in M5Paper schematic:

@loboris Yup, quick update that after I've made the comment we've discussed and decided to release all schematics as too many of you guys requested it ! all schematics now published in our documentation.

It was a wise decision.

@macias said in M5Paper schematic:

Hello,

Where I can find complete schematic for M5Paper?
I saw it after device was released but now only useless image is available as a schematic. (https://m5stack.oss-cn-shenzhen.aliyuncs.com/resource/docs/schematic/Core/m5paper/M5_PAPER_SCH.pdf)
If anyone has a complete schematic please share it.

Thanks

For me this link works and schematic pdf is returned.
In case anyone have a problem downloading it, you can get it here: https://loboris.eu/ESP32/M5Paper_schematic.pdf

@skink said in M5Paper:

hier kannst Du sie bestellen !! "https://eckstein-shop.de/M5Stack"

eckstein-shop.de: Delivery time : approx. 61 - 63 days

Still 8 in stock for immediate dispatch at Distrelec.

@felmue said in M5Paper power management:

Hello @loboris

if I read the schematics correctly in power off mode signal PS_ON is low, FET2 open, PWR_EN pulled up by R35, FET1 open, VBAT zero and VSYS zero as well, therefore the values of R30 and R33 shouldn't matter since SY7088 is without power. Or am I missing something?

BTW: The RTC will drain the battery even lower as it is directly connected to the battery and runs until 1 volts.

Thanks
Felix

Thank you, I've missed that.
RTC current is <1uA, so it should not be a problem.

@wolli01 said in M5Paper:

It would be nice if I had it too. Unfortunately I can't find a supplier in Germany who delivers it.

Distrelec has 17 left in stock. I've received mine in less than 18 hours (Netherlands -> Croatia)

There is a potential issue with M5Paper power management.
SY7088 boost regulator is used to generate a stable 5V voltage used used for all other voltages.

When the system is in power save and power off modes, resistors R30 & R33 values causes the constant current consumption of ~254 uA which leads to quite rapid battery discharge. At least 10x higher values should be selected. From Data sheet:

it is desirable to choose large resistance values for both
R30 and R33 . A value of between 10kΩ and 1MΩ is
recommended for both resistors.

Furthermore, SY7088 shuts off the output only at ~2.3V which couses battery overdischarge!