English

New FP2 Motherboard

design
Tags: #<Tag:0x00007f9ff97d5140>

#1

Hello,
I’m about to create a new motherboard for the FP2 that doesn’t need any changes to the other modules.
I decided to do so, because many people don’t want to buy the FP2 in 2018 but still like the concept of an open fair cellphone.
I use KiCAD for the board design, because it’s a good alternative to really expensive Eagle.

To the Fairphone 2 users:

The specs are quite fixed. They’ll probably look like this

  • Intel Atom x7-z8750 (with x86 for Windows support)
  • 8gb Micron 800mhz RAM
  • 128Gb Micron eMMC
  • Wifi, Bluetooth, GPS, 4G (probably with about 150mbt/s)
  • TI battery charger IC
    -Added: Dual SIM
    -Added: 100mbts wifi
    -Added: 150mbts LTE

What I’m not sure about is whether I should include a microSD Slot and whether it should have DualSim.
If you want to give me feedback or have any other features I should have thought of, you’re free to tell me.

To the Fairphone team:

I really like to cooperate with you, because currently I’m developing a 12 layer board on my own which is NOT easy.
I also need some precise dimensions of outlines of the current PCB used in the FP2 and If possible the pinout of the connectors (LCD, Camera, Sensor array, Bottom module)
Sadly I can only show some of the important Datasheets and the KiCad files with areas blacked out or to people that have an Micron account and have signed an NDA with Micron.
I hope you can understand that last one.

Leonhard Bandilla


:pencil2: FP 2/3/... Modules & Wishlist
How should I convince someone of a phone with dated software and hardware?
:pencil2: #wearefairphone Community Projects
Newcomer: Root, LineageOS & Upgrades
#2

Wow, you really think you can do this?

About help from the Fairphone team: I wouldn’t count on it. It’s a very small team and they are all super busy and if they haven’t released the necessary documentation so far they probably won’t take the time to release it now that the FP2 is already almost 3 years old.


#3

I think if you realy belive in yourself you can do whatever you want.
I think I can even do this on my own but I need at least the pinout of the modules to make it happen
I hope that they will give me the neccessary documentation, because that would be a second chance for the concept of the FP2
I would even given them the Gerber files when I’m done…

PS:That doesn’t mean that it’s easy - it remains challenging, but doable :slight_smile:


#4

@Leo_TheCrafter I encourage you to do so . Worst case scenario: you learn lots and become interestingly employable. Best case scenario: you are a hero.

I hope they provide you with the info you need.


#5

With the Intel atom processor i have a lot of io. Eg I have 7 i2c interfaces and also some other interfaces like FstSPI. I really need some ideas for features. By using 12 PCB layers I can make everything extreamly compact so I can adopt many features you ask me to implement.


#6

This wiki with many inspirations comes to mind: ✏ Back-PCB Wiki (Ideas, Tutorials, Showcases, ...)

FMPOV, I think that NFC has been requested quite often and it is something that FP2 really lacks badly in comparison with the competition.

PS.: Adding @Monica.Ciovica: Maybe you can answer on this:


#7

And this one: ✏ FP 2/3/... Modules & Wishlist


#8

Awesome and impressive project @Leo_TheCrafter. But I have some questions:
Are you just like to do the PCB layout?
Why an Intel CPU?
Who will do the soldering and assembly process?
Are you able to combine your PCB with the existing modules in view of the software programming?
What will be the operating system?
What are your expected costs?
Will the finished board be as fair as the original is?

Don’t get me wrong, I just ask in view of your imagination how much work you will have with that for the next couple of months.


#9
  1. I’m going to make the PCB layout and after some prototyping and refinement, I will try to cooperate with Fairphone, because they have already experience with making fair components.
  2. I have chosen an Intel CPU, because it’s really easy to get datasheets for them (you can even find one on your own if you’re interested in the Specs) and support high bandwidth LPDDR3 memory and up to 8gb of it. They also have a way higher performance than ARM CPUs, especially if you consider that it has only a SDP (Scenario design power) of 2W and the most important reason is that it supports x86 so it can run Windows 10.
  3. No, probably just for some early prototypes
  4. That’s where i need help from Fairphone because they developed the modules, but from the hardware aspect it shouldn’t be too complicated
  5. With support for x86 it can run desktop grade Windows 10 and will be comparable to the GPD pocket, which uses the same CPU and the same about of RAM.
  6. If I really want to realize as many of the wishes as practical, it probably would be way over 200 Euros. An easy way to make the motherboard cheaper would be to use just halve the RAM and less eMMC storage.
  7. That’s one of many questions i have to check with the Fairphone team if they agree to cooperate.

Thanks you for asking me these questions. Always remember: they may even solve questions of other users


#10

Hi,

Please excuse my newbie question… Can USA carrier support be improved with this new MB? I have experience with KiCAD and can offer some help, if needed


#11

For many Europeans you need dual-sim. Especially for people living near borders mostly having a domestic and a foreign sim-card… or one for data-only an one for phone… or dual-use a work-sim and a private-sim…

And i think you should add an SD-Slot as bigger and bigger sd-cards only get cheaper with time extending the lifetime of the board without significant overhead.

But i doubt that there will be an android (or something else) for x86 ready2go, right? Especially with apps from the play-store without emulation layer. Because i don’t want to use windows on my phone, when everything else i use is unix-based and i expect a lot of friction between the windows-unix-front…
That would be THE counter-argument for me to not buy such a mainboard.


#12

Why would you want to run Windows 10 on a phone? I mean, sure, you could potentially use it as a portable computer, but the performance wouldn’t really be great.
Another question I have is about the Atom CPU in terms of power consumption. How do they compare to e.g. Qualcomm CPUs in terms of battery usage?


#13

“Worldwide LTE, UMTS/HSPA+ and GSM/GPRS/EDGE coverage”

Quectel

Yes with this high power LTE chipset the Fairphone could be sold worldwide


#14
  1. If there is enough space i will defenitly implement a dual SIM solution even if this would probably mean I would have to use NanoSims and a SIM multiplexer, but since i have enough space on the board thats no problem.Also a mirco SD card should be possible, because the Intel processor has got an hardware SD interface which supports high transfer speeds.
  2. With this SoC you can use any OS you want, even if it might require a bit of work. You can use Linux for example and emulate Android or use Linus directly. Native Android support might not work without some tweaking but I’m not that into Software Development.
    If anyone knows whether Android is supperted please comment.

#15
  1. Read the response to Drezils question it might answer your question.
  2. The power consumption is excellent because the CPU uses 14nm architecture. The reason there is just a SDP instead of a TDP value is that the power consumption depends e.g. how many cameras you have connected (up to 3) or which RAM you use. But compared to an Qualcomm which has an estimated power consumption between 2-3 Watts but has LTE integrated the Intel CPU draws the same amount of power but is way more efficient thanks to the 14nm architecture than the outdated Qualcomm 801 SoC

I hope I could answer you questions


#16

If it’s highly portable instead the performance doesn’t need to be really great.

I have a 5" touchscreen Windows 10 thingy (Gole1, also with Atom) lying around, which really came in quite handy from time to time … but then it has a rather normal set of ports for connectivity, so for a Windows 10 smartphone something like the Targus dock should better work :slight_smile: .


#17

Is USB Type-C (MHL) a possibility, too?


#18

First hit in DuckDuckGo:

They are in active development and have an Oreo RC released earlier this month.


#19

Kinda,
i can of course make the motherboard ready to accept USB C, I am even planing to use a TI 4A charger, but the bottom module needs to support USB C.


#20

If the need for anything regarding software development/support arises, I’m sure that the community devs can help out.