ePaper Display (6"-10") with <1s partial refresh and very low standby consumption

Other Hardware Displays
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Hello,

is there a ePaper Display with 6"-10" and <1s partial refresh + very low standby consumption?
I use this 6" Waveshare ePaper 800x600, 6inch E-Ink display HAT for Raspberry Pi, IT8951 controller, USB/SPI/I80 interface (waveshare.com) and the standby consumption is way to much. The Waveshare Support said there's nothing I can do about it. The problem is the IT8951 controller which can't go to sleep mode. My current solution is to shut down power supply after the refresh is done and power the display + controller again when there's a new refresh. That's working great except it needs like 1-2s to initialize which is in addition to MQTT server and RFID scanning a bit to much. That's by the way why the Display needs to partial refresh in under 1s. I'm open for suggestions, maybe changing the controller is an option. Or maybe there's a controller which switches on in milliseconds. The best solution would be a really low consuming ePaper + Controller in standby. And there's another problem. The ESP32 is also in sleep mode. The controller has to keep the data while being disconnected. I know that's much but I guess asking doesn't hurt.
Thank you in advance and best regards

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Hello Fabian, hello everyone,

this is a topic and question I am highly interested in, and I would appreciate to get any additional information!

Low power consumption with e-paper displays is easiest to achieve with e-paper panels with embedded controller, with SPI connection. And a low power connection module with the needed voltage booster circuit, such as the DESPI-C02.

But these e-paper displays have relatively low resolution, and longer full refresh times.

Many SPI e-paper display have "fast partial update", differential update, with refresh times of 0.3 to 1 second. But many of the bigger and higher resolution ones don't have differential refresh, either don't have the capability, or there is no waveform table available for this.

GDEW075T7 7.5" 800x480 is the one with the highest resolution I know that has differential refresh, measured partial_refresh_time = 1600; // ms, e.g. 1584124us.

7.5 inch high resolution 880x528 e-ink display module, GDEH075T90 (EOL) is the one with the highest resolution, but no differential refresh.

Big E-paper displays with parallel interface have higher resolution, support 16 grey levels usually, and have (full) refresh times about 1 second when used with a capable external controller.

There is a library that allows to drive parallel IF e-paper displays directly, I think with ESP32, with some simple support circuit for driving voltages: GitHub - vroland/epdiy: EPDiy is a driver board for affordable e-Paper (or E-ink) displays..
LILYGO T5-4.7 Inch E-paper ESP32 V3 Version 16MB FLASH 8MB PSRAM WIFI/Bluetooth for Arduino uses this library, or a copy of. I don't have experience with it yet, it waits for me to get played with.

DESTM32-T is the evaluation board from Good Display for their parallel IF e-paper displays.
DESTM32-Tcon-11 is the controller part of the demo kit. It can be used separately, but has a 16bit data bus and a lot of control lines.
This controller can be used up to the 6 inch HD large parallel e-paper display 1024x758 resolution, GDE060F3, it doesn't have enough ram for higher resolutions.

Raspberry Pi 9.7 inch Parallel e-paper display DERPI-T0A seems to be the replacement for higher resolution. It uses the IT8951 controller. It doesn't seem to be available to buy yet.

And then there is a whole topic related to this question:

Request for help to make ESP32 to work with 6" ePaper of ‘Dalian Good Display’ - Using Arduino / Displays - Arduino Forum

This project currently seems to be on hold, interrupted by the COVID-19 outbreak in India.

Jean-Marc

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Hello Jean-Marc,

thank you for your answer. These Displays sadly seem to have no advantage to the current solution but this

looks really interesting. 450ms is fast and the esp32 doesn't consume much in deep sleep. I will test it definetly!

Thanks again and best regards
Fabian

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