MDFPGA: a HUB75 display controller base board using a Pi Pico W and an iCE40UP5K

A schematic is included here, along with the KiCAD data files, which are in KiCAD 6 format.

PCB design

The PCB is a 4 layer board easily built by any random PCB house.

Project overview

This board is the hardware for my Matrix Display project, which is spread across three repos: this one, a repo holding the Pico W firmware, and an optional one that holds the HUB75 display controller, which is implemented in Verilog.

Once up and running, you will have a 64 x 32 LED matrix display, presenting information from your Home Assistant system or, in theory, any other system that publish data in a suitable format via MQTT.

Hardware description

• Power via 5V barrel jack
• A Pi Pico W (obviously)
• A DS3231 (PDF) I2C Real Time Clock
  • CR122t battery backup
• IDC16 HUB75 connector attached to the Pico W
• Buzzer
• iCE40UP FPGA
  • N25Q32A (PDF) 32MBit SPI Flash
  • IDC16 HUB75 connector attached to the FPGA
  • LED

Possible gotchas

The board revision included here fixes some minor issues I found in the board I use on a daily basis:

• The CR1225 conenctor has been moved a few mm to make it easier to insert and remove the battery.
• The screw terminals, which power the HUB75 panel, have been pointed in the oposite direction, making them easier to access.
• More vias have been added around the 1.2V power pin on the linear regulator.

References

• Matrix Display The projects main repository. which holds the firmware source code.
• HUB75 Controller A HUB75 LED matrix controller implemented in Verilog.