A minimal single board computer using
Allwinner A10 SOC
Update on 6-Jun-2013:
Kicad drawings for a prototyping board having A10, PMU, 1GB
RAM,
HDMI, TF card and all the ports connected to FPC sockets have been
done. schematic is
HERE.
Update on 31-May-2013:
The schematic
and layout has been completed using Kicad. The initial plan was to do
the PCB using PADS but later on decided to use the Kicad output.
The DDR delay matching is done manually. The latest Kicad files, with
corrections and inputs from Joe Michael, is
HERE.
Most probably it will be send for fabrication next week. The layout without
ground planes is shown below.
A more compact layout: A
version with DDR data lines swapped for better layout also has been made.
First posting on 27-Mar-2013
Objective:
Make a minimalist SBC and make all the details including schematic, PCB
and Gerber files open without any restrictions, so that it can be
used as starting point for special purpose modules.
Work Done:
The schematic and layout files have been made using Kicad, thanks to
the inputs from Luke Leighton and Joe Michael. At the moment, Kicad
does not support the length matched tracks, required for DDR3.
But keeping the schematics in Kicad making sharing easy. One can also
make a case to the Kicad developers to add this feature. At present, the PCB
will
be done using PADS software.
Work Ahead:
The schematic need to be cross
checked, the A10 databook has many mistakes and I have relied on
resources from the web. I have never done DDR3 designs in the past,
there could be errors in the schematic. I hope those who know better would
help in making corrections, to reach working design. Once the schematic is
corrected, the
whole thing will be redone in PADS to make prototype boards.
The board has SOC, DDR3 RAM, MicroSD, HDMI, 3 USBs and some headers.
The plan is to get Linux booted from SD card. No NAND flash, USB-OTG or
battery. Only a 5V input via a micro USB connector.
If this works there may be a stand-alone version of expEYES.
Joe Michael got the boards fabricated. There were some errors in the layout.
In any case, we could not get it working.