Looking for open source pcb for FPGA SoM, Zynq, Artix, Cyclone 4/5 - Page 1
Forum section: electronics / general

author: polcad
author_rank: Contributor
timestamp: April 04, 2025, 08:55:53 pm
content: I am looking for an open-source FPGA PCB design featuring one of the larger FPGAs. Ideally, I would prefer a Zynq 7010 or, even better, a 7020, but Artix, Spartan, or Altera Cyclone 4 or 5 series would also be acceptable (in this order).The board needs to connect to multiple high-speed ADCs, so as many high-speed I/Os as possible are desirable (64 would suffice). Gigabit Ethernet is a requirement as well. Additionally, some onboard memory is needed. The board should be ideally in SODIMM format. However, as long as the PCB source files are available, I can adopt boards with other type of connector and the rest of the design to meet my needs.The board will be used for analog signal sampling and processing, so a large number of LUTs/gates is essential.The closest board I found is this one, but unfortunatelly no pcb source files are obtainable.https://aliexpress.com/i/1005007847728268.htmlDoes anyone know of such a design?

author: asmi
author_rank: Super Contributor
timestamp: April 05, 2025, 12:36:44 am
content: Why not design your own? It's not very hard, and there are plenty of schematics out on the Internet. Besides, these types of boards require controlled impedance, which means they are designed to a specific stackup which may or may not be available from your PCB fab of choice, and adapting existing layout to a different stackup can take almost as much time as full layout from the ground up.

author: polcad
author_rank: Contributor
timestamp: April 05, 2025, 09:12:06 am
content: I realize that these boards require cotrolled impedance.Why not to design my own?- time- pcb layout is the most boring job in the world- getting the design right with FPGA, DRAM and ethernet is a lot of hassle.- instead of prototypig and debugging I would prefer to just buy a ready made board, proven design.QuoteAny examples?

author: samofab
author_rank: Regular Contributor
timestamp: April 05, 2025, 10:15:39 am
content: Try this:https://github.com/EEVengers/ThunderScope/tree/master/Hardware/KiCad/FPGA_Module_Rev2But note the aformentioned problem with availibility of specific stackup.Also, the connectors are hard to align perfectly when hand assembling (and the layout is very unforgiving to misaligned connectors).Better just buy a ready made module (this one has roots in one of the Trenz Electronic offerings).

author: asmi
author_rank: Super Contributor
timestamp: April 05, 2025, 12:45:44 pm
content: Quote from: polcad on April 05, 2025, 09:12:06 amDDR3 runs pretty slowly on all of platforms you've mentioned, and so layout is rather forgiving. I have never had any problems with my ddr3 layout on any of my designs, it always worked from the first try. 1G Ethernet is even easier than that as it's just a few traces.But on the other hand, you will get a board that matches exactly what you need - exact capacity and interface width of DDR3 you need, whatever other peripherals you require, also no need to mess with alignment of high-speed connectors (because everything will be on a single board), and all of that in exact shape and size you need.Quote from: polcad on April 05, 2025, 09:12:06 amYou can take schematics of any of Digilent boards as a basis, they all have almost full schematics published (the only part they don't show is their USB-JTAG-UART programming circuit, but if you need it, I can give you schematics of that part). Or you can use schematics of one of my boards (I've attached it) - it's got A100T, DDR3 SODIMM x64 (supports up to 8GByte SODIMM), 1G Ethernet, HDMI out, and a bunch of high-speed connectors. It's had been proven in hardware:https://www.eevblog.com/forum/fpga/planningdesignreview-for-a-6-layer-xilinx-artix-7-board-for-diy-computer/msg5134983/#msg5134983Although it's probably an overkill for your needs, but there is a lot of free IO, and even 4 6Gbps MGTs.

author: polcad
author_rank: Contributor
timestamp: April 06, 2025, 12:06:31 pm
content: Quote from: samofab on April 05, 2025, 10:15:39 amStackup is never a problem. Most companies I know would build the stuckup to your design. Although they are not the cheap chinese pcb manufacturers.