Add a certain bi-stability to your life with an EInk Breakout Friend Adafruit - your fun friend who is happy to help out when you want to work with EInk/E-Paper screens. Fortunately for us, just about all EInk small and medium size displays manufactured today have a standard 24-pin connection. This card will add all the power supply support circuits and level change so you can attach your favorite screen (up to 4.2" tricolor) and connect it to your favorite development card.

Using our CircuitPython or Arduino libraries, you can create a frame buffer with the pixels you want to activate and then write it on the screen. Most simple cards leave it at that. But....almost all EInk displays are write-only and many allow you only to update the full (not partial) display. This means that you must buffer the complete image you want to display, taking valuable RAM.

The Eink Friend is much more user-friendly - it comes with a 256 Kilobit (32 Kilobyte) SRAM chip. This means that you can control up to a 4.2" 300x400 tricolor display (300*400 * 2 colors / 8 bits per byte = 30KB).  This chip shares the SPI port used by the eInk display, so you only need an additional pin. And, no more frame-buffering! You can use the SRAM to configure what you want to display, then mix the SRAM data with eInk when you are ready. The library we wrote does all the work for you, you can simply interface it with it as if it were an Adafruit_GFX compatible screen. If you prefer not to use the chip, our libraries will automatically use the internal RAM of the microcontroller/microcomputer.

For very low power consumption applications, the integrated 3.3V controller pulls out the Enable pin so that you can turn off the power to the SRAM and display. By default, the RESE resistance is set to 0.5 ohms, which is the most common value, but by cutting or welding the lower solder bridge, you can set the resistance to 3 ohms.

Supplied assembled and tested, with a connector. You will need a soldering iron to fix the connector for a breadboard n or to install it in your project. For use with just about any EInk display with a 24-pin FPC connector. Check these diagrams to make sure your display matches before you buy.

Technical details

Product dimensions : 34.7 mm x 21.5 mm x 3.5 mm / 1.4 in x 0.8 in x 0.1 in
Product weight : 3.4g / 0.1oz

Librairie

Adafruit EPD Library