Tiny E-Paper breakout board

I decided to design this pcb after testing many other e-paper driver boards (see here: https://hackaday.io/project/193939-inkycal-your-own-e-paper-dashboard/log/227090-the-driver-board) and found that most of them were either too bulky, had unnecessary components, were too expensive or just difficult to use.

24-pin SPI E-Paper displays

Most low-cost e-paper displays have a 24-pin 0.5mm pitch and are driven via SPI. To drive these displays, you need to add a few electronic parts and connect the SPI pins from the driver board to the Raspberry Pi or Microcontroller. Furthermore, some displays require a 0.47 Ohm resistor at a specific place of the circuit while others require 3 Ohm resistor. All of this can be combined into a single compact board. Starting with e-paper sizes from as little as 1" and going to much larger displays like the 13.3" one, as long as the display has a 24-pin flex-cable, this teeny driver will be able to drive it. All you need to do is solder 8 wires from this PCB to your Raspberry Pi / Microcontroller with 3.3V logic and power supply. 

Why not use existing ones?

I wasn't quite happy with the currently available driver board like the Waveshare one. While it offers convenience, quite a few users have had bad experience with torn flex-cables and a lot of difficulties finding out which way to connect the display and extension boards. Furthermore, as the Waveshare driver board needs to be stacked, it makes everything too bulky to fit in any ordinary photo frame, requiring users to get extra thick frames or having to modify the frame to make the electronics fit inside.

I wanted to improve the design by making a universal driver board for most serial e-paper displays which should as compact as possible using teeny components and footprints, using a latch-like connector to easily insert and remove the fragile flex cable from e-paper displays, adding an option to select between 0.47 Ohm and 3 Ohm required by different e-paper displays and adding mounting holes so it can be easily integrated and mounted.

The PCB

With the design completed, it was now time to order the pcb. At this point, I'd like to compliment my favourite pcb manufacturer, JLCPCB for their affordable prices, large selection of pcba components and ease of integration via EasyEda. JLCPCB is trusted by over 5.4M engineers all over the world, with rates starting from $2! Register with this link to get $80 coupons

The result was a driver board barely bigger than your thumbnail, measuring just 25x20mm. It weighs less than 5 grams in total, is ultra-slim (<5mm height) and has all the features I wanted (slim and compact, a connector which doesn't slide or damage the flex-cable, option between 0.47 Ohm and 3 Ohm)

Features

• Very small PCB, measuring just 25x20mm. It's hardly bigger than your thumbnail!
• Supports most 24-pin SPI e-paper displays including 3-colour ones, even those from electronic shelf labels!
• ROHS certified PCB & components. No lead, no sweat!
• Ultra-slim (less than 5mm height in total)
• Easy-to-use connector for inserting and removing flex-cable connector (no more sliding)
• Can be used with Raspberry Pi and Arduino/ESP32 or a different microcontroller

Pinouts

• BUSY
• RST
• DC
• CS
• CLK
• SDI
• GND
• 3.3V