Using FOSS for OSHW project. Design of complex 64-bit ARM board with KiCAD and our suggestions how to make KiCAD better

1. Designing with KiCAD of 64-bit ARM board
Tsvetan Usunov, OLIMEX Ltd
FOSDEM 2016
Using FOSS tools for OSHW project

2. $whoami
OLIMEX Ltd – for 25 years we design
and produce development tools, boards,
devices, small Linux SBC.
We love to do things better and to share
how we do it!
Using FOSS tools for OSHW project

3. Out of about 600 different products on our web
site half are with OSHW Licensee.
Distributors in 50+ countries: Mouser, Digikey,
Farnell, Conrad, TME, Amazon etc which proves
that OSHW model is not incompatible with the
business.
Using FOSS tools for OSHW project

4. Using FOSS tools for OSHW project
For 25 years we have dealt with hundreds of designs
done for customers:
- analog design, medical
- digital design, microcontrollers
- high speed, RF
- high density
- low power
- low noise, high precision
- high power, motor drivers
- mass volumes, consumer
- instruments, industrial boards

5. Using FOSS tools for OSHW project
CAD experience:
Orcad schematic, simulation DOS 1991-1998
CadStar PCB layout DOS 1991-1998
Eagle 1998-present
KiCAD 2015-present

6. Using FOSS tools for OSHW project
OSHW projects need FOSS tools!
First FOSS CAD evalulation back in year 2008:
gEDA
KiCAD
All of them were not mature,
but we were keeping eye on them

7. Using FOSS tools for OSHW project
Decision to move to KiCAD march 2015!
- old developers resistance
- everything is matter of habits
-no one wants to break his comfort
- new guinea pig employee
- daily crashes, small bugs, which are fixed really fast
- always use latest builds!
- workshop – standard repo, windows obsolete
- anything different from Ubuntu – source builds

8. Using FOSS tools for OSHW project
October 2015,
20+ boards later, we learned more
KiCAD was performing better and better and we decided
to do something more serious:
x4 core 64-bit ARM board with high speed memory,
Ethernet etc.

9. Using FOSS tools for OSHW project
What we found during the development:
New tool – many things which our people though are not
possible are implemented but poorly documented
We definitely need book for KiCAD – from the beginning
with featuring all possibilities which the product offers.
3D models are still pain to make

10. Using FOSS tools for OSHW project
Now some feedback about some things which could
improve the user experience.

11. Using FOSS tools for OSHW project
Schematic:
- user definable schematic grid and shortcuts to change
- highlighting net list
- do not allow components which are connected to wires
to disconnect when move or rotate
- allow to group and move net labels separately from the
nets
- ERC do not think it's error to place two labels on same
net
- allow easy way to change / save ERC defaults

12. Using FOSS tools for OSHW project
Schematic Library:
- please allow partial copy of existing component to new
one

13. Using FOSS tools for OSHW project
PCB footprint editor:
- please add polygones and rectangles in solder paste
layers
- please allow us to add text at different than 90 degrees
angles

14. Using FOSS tools for OSHW project
PCBnew:
- short cut for highlight netlist
- please add layer stackup information for multilayer and
calculate length of the tracks correctly
- some DRC errors should be possible to mark as
approved
- we want to see DRC errors in the dialog box not only in
the report file
-DRC must report overlapped pads!

15. Using FOSS tools for OSHW project
PCBnew II:
-DRC do not report errors for tracks which go outside
PCB dimensions
- DRC do not report 45 degree angle violations while
routing
- moving block of components sometimes work
sometimes don't
- we need lasso polygone group selection, rectangles
group is not enough
- mirror sometimes doesn't work when you move
components from top to bottom layer and vice versa

16. Using FOSS tools for OSHW project
PCBnew III:
-push and shovel router sometimes move tracks
sometimes don't
- even if walk around is selected sometimes interactive
router moves tracks and pads
- interactive router sometimes moves pads and tracks
which are far away from the track we move
- DRC do not think as error if we place drill in SMD
component pad

17. Using FOSS tools for OSHW project
Pick and Place generator needs more flexibility:
- add offsets
- add coordinate 0,0 and directions

18. Using FOSS tools for OSHW project
Gerber generator:
- copper fill polygones sometimes violate DRC
- please add DRC to Gerbviewer
pad/pad trace/trace drill/drill
- panelization will be big advantage

19. Using FOSS tools for OSHW project
What we think with make KiCAD even better
Circuit simulation

20. Using FOSS tools for OSHW project
What's are our new plans for KiCAD for 2016:
- FPGA iCE40HX1K board/shield
- DIY modular Laptop
- Book / tutorial how to build PCB from the start to
production

21. Using FOSS tools for OSHW project
Conclusion:
KiCAD is now one solid platform for PCB designing even
for complex circuits.
Few small things are missing to make it more user
friendly and easy to use
It's improving very fast and this should keep going and if
continues with same tempo just in few years it will be one
of the best tool for PCB design.

22. Using FOSS tools for OSHW project
Thanks!
© 2016, released under CC-SA-BY-2.0