BGA-320 footprint for the Cologne Chip GateMate FPGA

[ak-fau]

BGA-320 footprint for the Cologne Chip GateMate FPGA
(18x18 matrix with 4 balls removed).

Matching symbol PR KiCad/kicad-symbols#2578
Matching footprint PR KiCad/kicad-footprints#2183

Datasheet

Footprint preview

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[cpresser]

Not sure about the pad_diameter and mask_margin values. Please clarify how you deducted them.

Since I am interested in that part as well I might just call the people at ColongeChip an ask.

[cpresser]

How did you deduct those parameters? I can't find them in the datasheet.

I would suggest to put this instead:

  ball_type: 'collapsible'
  ball_diameter: 0.45

(that feature was just recently introduced in #592)

Omit the mask_margin, that way it is controlled by the DRC of the board. I don't see a recommendation from the manufacturer.

[ak-fau]

How did you deduct those parameters? I can't find them in the datasheet.

No, they are not in the datasheet, and, apparently, my initial submission is incorrect:
-- general recommendations for 0.8mm pitch/0.45mm ball diameter FBGA packages
(based on documents from Intel, Xilinx, Lattice, and NXP) are NSMD pads
0.34..0.40 mm in diameter. With the ipc_definitions.yaml we are going to have 0.35mm
pads, if I'm not misreading it.

Since I am interested in that part as well I might just call the people at ColongeChip an ask.

I've sent the question to a support contact there. Let's see if and when they
have something to answer. Of course, you may call them too, it may be a faster
way to get the info. Thanks.

I would suggest to put this instead:

  ball_type: 'collapsible'
  ball_diameter: 0.45

(that feature was just recently introduced in #592)

Generally, makes sense and I've tried to implement the changes,
but, it doesn't work for me right away for a number of reasons:

• I cannot find an example of its use in any other BGA package
• "collapsible" vs "collapsable" -- ipc_definitions.yaml makes use of the later,
  while the correct spelling is the former (as you suggested above)
• the bga.py script complains about missing pad_diameter:

~/Work/kicad/kicad-footprint-generator/scripts/Packages/Package_BGA$ python3 bga.py ccgm.yaml 
Building footprint for parameter set: BGA-320_15.0x15.0mm_Layout18x18_P0.8mm
Traceback (most recent call last):
  File "bga.py", line 232, in <module>
    generateFootprint(configuration, cmd_file[pkg], pkg)
  File "bga.py", line 174, in generateFootprint
    size=[fpParams["pad_diameter"], fpParams["pad_diameter"]],
KeyError: 'pad_diameter'

Perhaps, I've just missed some critical step to refer to the proper IPC file,
but I don't know how to do it, sorry.

Omit the mask_margin, that way it is controlled by the DRC of the board. I don't see a recommendation from the manufacturer.

Agree.

[ghost]

I just called CologneChip and taked to Mr. U.... (redacted for privacy reasons).

The important information is that the package and pinout will change slighlty. They are in the process of finishing the documentation for that. Once the up-to-date documentation is available they will provide it to us.
Thus, this PR and the symbol-PR will have to wait a few weeks.

[myfreescalewebpage]

@ak-fau any news following the comments made on this PR ?

[ghost]

There is still no news from CologneChip. Thus, this has to wait.

[ak-fau]

I sent a reminder to CologneChip a few minutes ago, let's see if/when they have any updates to the documentation.

[ak-fau]

CologneChip replied within 3 hours, wow! Their reply came from the same Mr.U... cited above.

They have experienced a significant delay with a tapeout of the final version and haven't got to the documentation update yet. The final silicon is expected in early January. Updated documentation will be available at some date between now and January. Then we will be able to proceed with this and two linked PRs.

Quotation from Mr. U... e-mail (unrelated paragraphs are edited out):

Due to very long delays for the final mask tapeout, we did not get
around to updating the documentation as planned. Fortunately, all the
data is now at Globalfoundries so that we can now concentrate more on
the documentation and will prioritize your concerns. We sincerely
apologize for the inconvenience. The situation turned out to be very
unsuitable for us, too.

[skip]

Unfortunately the pinout
had to be changed slightly. We are still waiting for feedback and
information from our packager. I would ask you to wait with hardware
manufacturing until we have the data, so that you guys can continue on
the pull request.

The hardware manufacturing he is referring to is the module I'm working on:
GMM-7550