Worklog (finished) Swiitch 2.5 - BocuD's third Wii Portable

[BocuD]

The Swiitch 2.5

So, as some of you may know I've been working on a new wii portable again for about 10 months now. The main goal of this project was to give it the same form factor as the Swiitch 2.0, except make everything as neat as possible. That has been mostly successful during the initial project, but while working on it for so long the entire project got very bloated and it kinda lost its "neatness". Thus i decided to start over, but reuse the good stuff I had in my previous design.

The main gimmick thing of this portable is probably the fact that everything is on a single board, with the wii and stuff like batteries stacked on top of that, allowing me to make it even thinner then the previous one, while increasing the battery capacity by around 30% and also making the heatsink about 5x as big. This is mostly because well, the previous one had a tendency of getting hot, and this eventually killed it.
When it comes to features, specs whatever this should be a no compromise thing.
Current list of features:
Power:
- USB C PD charging using the STUSB4500
- BMS system that's similar but not identical to Gman's Wii PMS system (it doesn't allow me to use a 15v power source, but I want to use the switch charger)
- Voltage regulators that are actually stolen from Gman as my own design failed
Screen & audio:
- 5" IPS screen
- Integrated lcd driver using the RTD2660, which will probably end up running custom firmware (more on this later)
- LM49270 amp
- These speakers (identical to the ones in the Swiitch 2.0)
Controls:
- Switch joycon sticks
- GC+ 2.0
- White New 3DS dpad and abxy buttons
Wii:
- LMAO v2 ish trimmed wii using Aurelio's nand boards
- Custom CNC'ed heatsink
Other:
- 3D printed case (won't be painted, rather over extruded and sanded down)
- Kingston microSD card reader
- USB Data switching
- PWM controlled fan based on the temperature of the wii (there will be an NTC under the heatsink)

This list might change in the future. hopefully just for the better
Once I complete parts of the pcb or case I'll post pictures, tho I don't see a reason to post some of them yet.
Thats all for now. If I get any good progress going, I'll be updating this post as well.

 

[Nold]

LMAO v2 ish trimmed wii using Aurelio's nand boards

... no seriously, i'm really exited about this one! I love project series, that evolve & improve over time.

 

[BocuD]

So, yesterday I made some progress with that LMAO v2 ish wii..
I've got to say, those nand flex boards make it a lot easier

 

[DeoNaught]

New nand board slogan coming in; "So easy, even Bocud can do it!"

These boards are hot

 

[Nold]

btw.. nice solder...

 

[BocuD]

btw.. nice solder...
View attachment 8755

Ayy that's pretty much exactly the same stuff

New nand board slogan coming in; "So easy, even Bocud can do it!"

These boards are hot

Yes very much

Anyways, I have some actual progress. Pretty much everything (except like 2 things) on the PCB is completed so in the next week or so I'll be looking through everything some more, optimising the last bits and then hit that JLC order button. I looked at a few options for CNC cutting the heatsink and I found a manufacturer in Italy thats about as cheap as all the Chinese options so I'll probably go with that. Case design is nearly done but not final.

I didn't bother 3d modelling all the buttons again, but I did test prints for the parts where the buttons go in.
This is pretty much the final board:

Currently there's 2 things still somewhat missing; The OSD buttons for the LCD driver, and part of the USB Data switching. Both will be controlled by the LCD driver and a pic instead of "automatically switching" in the end though, so not that interesting. There will be a button combination (probably volume up plus power instead of just power for example) to enter USB acces mode. That way I can just use the other regs instead of adding in another 3.3v and 5v reg just for the data switching.
Completing this build in time is going to be extremely challenging considering the amount of finals I'll have in the next two weeks as I don't have a lot of time after that, but we'll see I guess

 

[Ekterm]

That is sweet, I love how putting everything on one custom pcb makes it so much cleaner!

 

[DeoNaught]

I looked at a few options for CNC cutting the heatsink and I found a manufacturer in Italy thats about as cheap as all the Chinese options so I'll probably go with that.

I took a hack saw to my wii's heat sinks and that's what I'm using as a custom heatsink haha ¯\_(ツ)_/¯

to enter USB acces mode.

if you are in a pinch for time you could always just use the micro sd card adapter... and then it falls into the theme of Nintendo Switch conveniently

 

[BocuD]

I took a hack saw to my wii's heat sinks and that's what I'm using as a custom heatsink haha ¯\_(ツ)_/¯

I thought about that but a wii heatsink would be way too big. I thought about cutting up a gamecube heatsink as well but figured doing this is more elegant

if you are in a pinch for time you could always just use the micro sd card adapter... and then it falls into the theme of Nintendo Switch conveniently

I am using that actually
Just using this as well, for convenience lol

 

[BocuD]

So.. time for another update I guess
First, the PCB has had some massive changes. Its not done yet though so not gonna show it yet. Once I order it I'll show the final revision I guess lol.

Second; I finally got a Prusa! And hot damn is this printer amazing. I had some issues at first, but have pretty much everything I need to print some memes working now. So I did a test print of my case.. This was my third ever print on the printer and I have since adjusted a few things, but its still about 1000x better than my previous printer:

Third, I received a number or parts today. The batteries came in and they are 5100mah for some reason? I ordered 5000 but hey I'll take it!

They fit inside the case just right, but fitting the shoulder buttons in is going to be quite a challenge. For those I'm using a squishy tact, but not the well known orange ones. They were sadly unavailable at the time of ordering.. Anyways. I'm using these tacts: (edit, added image)

The one with the red button has a pretty high actuation force, while the grey one has a very low actuation force. This makes the dual tact system thing work very well and it makes it very easy to discern between a light and full press. The problem: the batteries are about as big as I can fit inside this case. Putting tacts on top of each other in the traditional sense won't work. For reference (this is not the actual mounting location, but the height shows the problem) I have about 5mm to work with:

Pictured is one of the two 105575 cells (5100mah each) in my case, though they are actually mounted on the bottom in the final design (see pic). As you can probably see I made sure that airflow would be good and there is an adequate amount of heatsink.

I think I have a solution by placing the dual tact buttons side by side instead of on top of each other, but I haven't totally figured that out. It'll come tomorrow. First there's the wiiboy stream..

 

[DeoNaught]

I don't want one...

I NEED one

did you find 5" ips screen? i remember you were looking into one, and then only one you could really find is the $50 with component

 

[BocuD]

Update time
Yesterday I made the last changes to the main board. This is the final version:

I didn't feel like generating a 3d model again so just pictures for now ayy
Anyways the final list of crap this board does / has
- 1V/1.15V/1.8V/3.3V regulators for the wii
- LCD driver
- Full 1S battery management
- 5V USB or PD charging through USB C
- Data acces while the system is powered off
- "Docked mode" ( ͡° ͜ʖ ͡°) details later
- GC+ 2.0, with LRA rumble
- Audio amp
- idk, I'm probably forgetting something but there you go
Sadly I forgot to add a header for the PWM fan stuff so that probably won't be in the final version lol. I also forgot the testpads for the lcd driver OSD buttons, which shouldn't be that bad since I won't use those in the final portable but it would be useful to say the least while working on the lcd driver firmware. I REALLY hope I don't find any other issues as the board is already "in production", aka no refunds. Oh well. I'm trying to cut down my BOM right now, as its ~230eur total.. trying to find the balance between having room for fuckups and not losing a kidney.
On a more positive note i figured out the shoulder button problem, but I'm not home right now so will post that in a later update. I think it's not unreasonable to think that I might just finish in time actually, assuming the board actually works.
TLDR: if you are making a board of this size triple checking everything isn't enough. Quintuple check everything. And then again, or something like that.
Anyways good luck to everyone else who's still on schedule, and uuh make sure you aren't missing anything when you order your boards lol

 

[Aurelio]

I swear, if BocuD wins this year contest I am going to be so mad at you, @Gman

 

[MRKane]

It's beautiful! I think I want it as a tattoo!

 

[thedrew]

@BocuD

This is insane work my man. All the detail and figuring out the layout and all on just one board is amazing. Watch out fellow contestants!

 

[LOCtroviser]

Your work looks beautiful! I'm looking forward to see that board totally populated with all the parts

 

[BocuD]

So today my pcbs and parts arrived, but tomorrow I'm leaving for vacation so I didn't have a lot of time to mess with it. Anyways, obligatory pics here:

Zoom in to get them details. I'm very happy with the quality of these boards to say the least. JLC really is much better then most other fabs I've used before. Whats also nice is that all the slots and holes are properly cut out, including the one for the lcd flex in the middle and the one for the right analog stick which I didn't expect. The silkscreen is also extremely detailed, and even the tiny text I have with some header pins
Considering I didn't have a lot of time and also the fact that I don't know what works and what doesn't, I decided to assemble the LCD driver on its own first, and then to just power it from a wii for now. So I did the memes with a stencil (taping over the parts other then the lcd driver and audio amp, not shown in the pic) and well, the first time it failed. Way too much paste. So I cleaned the board, made a better jig thing, and added some weight lmao

This time it ended up much better, so I then slowly assembled it. And HOT DAMN. Stencil + solder paste is amazing. Especially for the QFNs it made it much easier, but even for just passives and other small ics, they just align themselves perfectly. surprisingly, the only part I had issues with was the lcd driver ic, which was kinda weird since I hand soldered it before, but since it wasn't perfectly aligned and its too big for the surface tension trick it soldered on not correctly with quite a few bridges. So I removed it, put it back on it and this time it went on nicely. The first time I turned it on, there was some magic smoke from the SPI flash lmao. This dot should be on the bottom right damnit..

But, not to worry, we are still flying half a ship
I have more then enough RTD based lcd drivers, so I just programmed another chip and put it on. But..

Well rip.. The backlight driver works, which is good, and so does the audio amp. But the lcd driver isn't doing anything sadly. I thought at first the problem might be the crystal since I forgot to order the right caps and pulled some from another driver, but those were for an HC49 crystal which is much bigger. So I took the big crystal and wired it up, removing the smol one.

Still, nothing on screen, so I connected the stuff I used to work on the custom lcd driver firmware, and tried to enter ISP mode, but, no communication. On one end I think this is a good thing, cause this means it could be just a simple thing, and that the rest is good. But on the other hand, if this simple thing is messed up enough, it might require a board revision to fix it nicely (which isn't a bad idea as I forgot some other things, but I'd like to avoid it due to costs). Anyways, I'm sure I'll get it figured out lol, as I have about two weeks left to do the memes when I get back from vacation.

 

[BocuD]

So, bit of a late update.. But uhh
I came home last week, and fully assembled a board. All the regs were working, so I finally trimmed a wii.

Its similar to LMAOv2, but all screw holes are retained. I'll probably trim some more off of the sides later depending on if its needed or not. Probably not.
Anyways, it worked first try (surprisingly). So I slowly started testing the other stuff on the pcb. Stuff thats fully working:
- USB PD (charging from the switch charger at 15v )
- USB Data switching
- Regs: 1v, 1.15v, 1.8v, 3.3v (ldo and switching), 5v (step down and step up)
- All battery related stuff
- All audio related stuff

Some smexy pics

There are a few problems though; Here's a (maybe?) incomplete list:
I forgot to add a pad to connect the GCC data line to the gc+... So uhh soldering to a qfn pin is going to be fun I guess lol
I accidentally renamed a line some time after doing all the DRC checks, and that resulted in the pour for SW for the 5V boost reg not filling.. I fixed this (for now) with a jumper wire
I forgot to connect a few data lines to the lcd driver I would rather have to display more info (more on this later)
I forgot a 1.8v power connection to the lcd driver, which sadly made it not work.. can be fixed with a jumper wire
The dot for the lcd driver eeprom was in the wrong spot (not really an issue functionality wise, but should be fixed in the next revision)
The location for the joy con FFC connectors is slightly off.. can be worked around with separate breakouts and jumpers
Something is wrong with the implementation I'm using for the lcd backlight boost converter. This may have something to do with the fact that I'm using a cheap ass reg stolen from the stock rtd boards.. uhh fuck

So, its time for a revision. Each of these problems can be fixed in a shitty way (some of them have already been fixed / worked around) but that kinda defeats the purpose of this portable. The idea was, a single board, and literally as little wires as possible without putting the wii on the pcb as well. Having wires everywhere bridging stuff won't do it. If there were just 2 or 3 of these problems it would be fine and I'd at least finish it for the contest, but if I make the portable with all these problems now I'll end up having to redo it anyways, or I'll forget and then regret it lol. Given the fact that all these issues can be pretty easily fixed with a board revision I will probably still finish this meme in the next month or so though, just not for the contest sadly.
Oh well maybe next year
Good luck to the like 2 contestants who actually have finished portables

 

[BocuD]

Over the past few days i did a lot of cad stuff, as i need to wait for my boards anyways. And all i can say is damn. The prusa really is that good. The surface quality on the first layer (top and bottom) for example is just perfect, i literally can't see the layer lines even though its not sanded. I wonder how it'll look with some wetsanding..
Anyways, heres some pics of the progress rn:
First test print with abxy guides.. also the bed nozzle distance wasn't properly calibrated here.. oops

First good shoulder button tests (abxy fixed as well):

Volume / power buttons:

With screen:

Expect updates soon™
I'm making a lot of progress and shit is going well
And uuh can a mod move this back to the wii forum?

 

[Stitches]

Ask and ye shall get fish