[IC] 2018 Dec upadate Nano U2U USB to USB keyboard converter

[Bobnaive]

Haus's USB to USB keyboard converter topic:
https://geekhack.org/index.php?topic=69169.0
Big thanks to him.

So based on Hasu's schematic i re-designed this U2U.
i am trying to make the U2U much smaller.

because each USB port is very close, so they do not have too much space.
and if the U2U is small enough we can put it in the keyboard.

As we all know USB tongue's thickness is about 2.5mm.
But it is 2.5mm, it will be too tight. so we need reduce the thickness ASAP.

the 32U4 height is about 0.8mm, and i use 0.4mm PCB make it as thin as possible.
and i also draw a shell for it. Use 3D print to make the shell.
but due to 3D SLA technology, we can only make the thickness no more less than 0.5mm.
after all, plus all the things the thickness is around 2.5mm.

and this U2U is too much small, so i use epoxy resin to combine the PCB and shell.

according to this small area, i use 0402 resistance and capacitance.

this is my first version use green PCB.



this coin size is about 25mm


after this, i fix some bugs. and redo the PCB with Immersion Gold.
it makes USB Gold-finger more reliable, and black with gold looks better.

this is my final version.







right now the final size is about 13x27.5x9.5mm.

and i am not sure the gerber is correct, because i send PCB file to the factory instead of gerber file.

2018 Dec upadate
it is been a long time that i did not update this topic

right now, i made this nano U2U smaller.
the old one, the size is 12.5 X 28 X 9 mm
the latest one is 14.5 X 23 X 9 mm, 5mm shorter than before. as i know this is good for cable.

and I removed the switch, but left two metal contacts instead. I think the frequency of the switch is not very high once you have done the firmware.
You can use the dice to short the two contacts to simulate the switch

this time i use four-layer board. Since I used a four-layer board, I was able to wire it more easily.

and put LED on the top, hence you can change the color easily.

at last, the most important thing the USB receptacle is soldered on the PCB right now.
it make U2U much more stronger.

The following is a comparison of old and new

[sony]

This is pretty neat. Would definitely order one.

Sent from my ONEPLUS A3000 using Tapatalk

[Bobnaive]

thanks~

[Giorgio]

This is very interesting, because I hate programming all my keyboards, and because many of them aren't programmable. What's the expected cost?

Will this work with keyboards that support full nkro? Not that I need that, it's just that I don't know how to force for example 6 kro

[Damonskv]

A great solution, but how to be with reliability, I mean ordinary, mechanical durability?

[Atredl]

This looks really neat. I'm in for one for sure. Maybe two, just in case I step on the first one lol.

[duynguyenle]

I have a few questions:

1) This is really tiny, and that's nice, but I would be afraid of the PC-end of the device just breaking off, since it's just printed pins on the PCB material, which is quite thin. How will this hold up in regular use, especially with a USB cable dangling off the side of it? Is there an option to get a proper male USB-A connector instead of just the pins on the PCB like it is at the moment?

2) How much is this going to cost? Will you offer any sort of casing for it?

In any case, it's a really neat device, and I'll probably pick one up anyway just for curiosity's sake (if the cost doesn't break the bank, of course!)

[Bobnaive]

This is very interesting, because I hate programming all my keyboards, and because many of them aren't programmable. What's the expected cost?

Will this work with keyboards that support full nkro? Not that I need that, it's just that I don't know how to force for example 6 kro

I think it is not support full nkro, maybe no more than 6 keys. i can not test right now, cause i do not have NKRO keyboard.
i need borrow one from my friends. i will update this ASAP.

[Bobnaive]

A great solution, but how to be with reliability, I mean ordinary, mechanical durability?

Well, between the shell and the board is filled with epoxy resin. and USB-B port stick to the PCB with epoxy resin too.
i think epoxy resin is strong enough.

and since i made the first U2U in APR, I plug in and plug out everyday. It works well.

[Bobnaive]

This looks really neat. I'm in for one for sure. Maybe two, just in case I step on the first one lol.

Thanks

[Bobnaive]

I have a few questions:

1) This is really tiny, and that's nice, but I would be afraid of the PC-end of the device just breaking off, since it's just printed pins on the PCB material, which is quite thin. How will this hold up in regular use, especially with a USB cable dangling off the side of it? Is there an option to get a proper male USB-A connector instead of just the pins on the PCB like it is at the moment?

2) How much is this going to cost? Will you offer any sort of casing for it?

In any case, it's a really neat device, and I'll probably pick one up anyway just for curiosity's sake (if the cost doesn't break the bank, of course!)

1. print pin on the PCB is not strong as USB-A.
if you worry about this, you can use U2U without USB-B. put U2U without USB-B in the keyboard.

2. i am not sure about the price right now, i need calculate. I will make reasonable price for it.
i think case is not necessary.

[CursorTN]

Hey, saw this on Top Clack tonite!  Very interesting project.  Sign me up!  I'd for sure buy this.

[8064r7]

Given the fact I only lurk on GH and I'm here posting should point to how strongly I believe this is a good product to pursue development.

[rrrsss]

definitely interested!

[KorbenDallas]

This seems like real handy tool to have I'm definitely in if price is reasonable

[iFreilicht]

Very cool idea! If the price is right, I'd definitely get a few for modding projects.