Lattice iCE40 HX4K breakout / dev board

Introduction

This KiCAD project contains the design of a break out / dev board for a Lattice iCE40 HX4K FPGA.

I'm a novice at PCB design, so please don't assume anything here represents good practice. I was motivated to tackle this after seeing Matt Venn's iCE40 board. Some elements of the design are based on the TinyFPGA BX.

Features

• SPI flash for configuration.
• On-board clock.
• Powered by 5v from a micro USB connector. Regulators for 3.3v and 1.2v. Power LED.
• Single output LED.
• 72 GPIO pins broken out. sysCONFIG pins broken out for programming the flash. Cold boot config pins broken out.
• The USB data lines are connected to the FPGA. This makes it possible to program the board directly over USB using e.g. the TinyFPGA bootloader.
• 2 layer PCB.
• Designed for hand assembly.

Project Log

• 2021-06-07: I now have the TinyFPGA bootloader working.
• 2021-05-22: Confirmed that I can blink the on-board LED using the FPGA. I'm currently using an external programmer to load the configuration into the on-board flash. (See blinky.)
• 2021-05-12: First board assembled.
• 2021-05-10: Prototype boards received.
• 2021-04-22: Revision A of the board completed. Prototype boards ordered.