Design files of the RiskZero FPGA Workstation Single Board Computer.
The pre-production design files are linked below. The files are meant for review. Please e-mail me the remarks, comments, and suggesstions.
RiskZero design documentation, updated Sept/28/2020. In this file I am discussing the architecture, applications, and limitations of this design. Some of this discussion was posted to the mailing list. Highly recommended to read before committing to this board.
PDF schematics of RiskZero, updated Sept/29/2020.
OrCAD schematics, layout, and BOM, updated Sept/29/2020.
Production files, updated Sept/29/2020..
Draft firmware for RiskZero, updated May/24/2020. Right-click to save this file. This FW project was kindly contributed by Magnus Karlsson magnus at saanlima dot com in order to test whether or not LX9 can host the HDMI video. This is a very early draft reproduced with permission. It is not even using the RiskZero UCF yet! Its sole purpose was to verify that the HDMI firmware has a chance to fit. The LX9 utilization increased from 58% for the original SoC to 76% for the SoC with HDMI. It is a very optimistic result. Thank you Magnus!
The UCF file will be posted here when available.
All the design files, including gerbers and the BOM are provided "as is".
All the files are provided "as is". I will update this space when the files are reviewed by the manufacturing house.
Quoted production cost.
The following quotation was provided by PCBcart.com. The NRE is paid once. It consists of "tooling cost" and "jigs" in case of the last row. The cost of parts per board is very closely matching the Digikey cost. The last column provides the cost to manufacture one board with all the partial costs factored in. Shipping from China is not included to the total.
While PCBcart may not be the least expensive assembly house, I have used their services in the past and I can attest they assemble boards of high quality. Feel free to ask other vendors.
Quoted production cost of the RiskZero boards
Qty
$ PCB/ea
$ Parts/ea
$ Assy/ea
$ NRE
$ Total
$ Total one brd
5
31.60
152.54
120.15
224.86
1746.31
349.26
10
21.96
137.93
71.16
224.86
2535.36
253.54
20
16.43
134.41
42.47
224.86
4090.91
204.55
100
9.18
113.17
15.00
434.86
14169.74
141.70
Conclusions drawn from the production cost.
As you can see, the cost of the six layer board is low. Parts are the major cost component. As far as I know, PCBcart orders the parts from Digikey, Mouser, and other reputable sources. We can do very little about this cost. (Look at the BOM, where I summed the Digikey part cost.) The prototyping quantities are known to be expensive and this is what we are seeing. Assembly cost is low, and the NRE is reasonable. All in all, not much room to save. The major parts are two ZBT chips and one FPGA, which are essential for this design.
In order for the board production to be feasible, we need to add the in-house expenditures for testing and packaging the boards. Assuming one hour of our time per board (optimistic) we need to add about $100 per board. Power supply and cables will add about $25, unless you are happy with a USB cable and no power supply. (The board is ready to be powered via the USB.) Shpping and handling would add another $25 domestically, and who knows how much internationally. All in all, add $150 per board to cover the extra in-house labor, the cables, and packing.
The selling price should be about 2x higher than the total production cost, both the assembly house and ours added together. This is a common rule. Realistically, the board should be priced at about $300 to $400 if we make and sell one hundred of these boards.
However, you can make a bunch of these boards yourself. Either find a less expensive vendor (for example, EasyEda or Seeed Fusion assembly services). Or order the bare PCB and the parts, and assemble your boards by hand. All the parts can be soldered by hand if you know how. You will need either a hot air nozzle or the reflow oven for the "popcorn parts" (resistors and caps), and a fine iron for the FPGA and the other chips. From my experience, it will take two days per board. You will save on the assembly cost, if you put in your own labor.
Please feel free to manufacture these boards if you wish! Please let me know how your production cost compares with the quoted numbers.