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Would it be possible to make a USB Hub from scratch? Like, designing a PCB, and hand soldering components on to it? What microchip would I have to use as the controller? Is there a simple controller chip I could use for, say, a 4 port hub? I know I'm getting a bit hopeful here, but are there USB hub ICs in the DIP package?

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    \$\begingroup\$ Depends on your understanding of 'complicated' \$\endgroup\$ Jan 14, 2018 at 17:12
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    \$\begingroup\$ You can, but what's the point? A conventional MCU is not involved, instead a special purpose hub IC has almost everything except for supply and support components. This wouldn't really seem to make any sense as a project unless you are prototyping a product, or need to combine a hub with other capabilities. Even then (for example, contemplating a production test rig which measures device power currents) it may make sense to buy a hub and trivially modify it. \$\endgroup\$ Jan 14, 2018 at 17:54
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    \$\begingroup\$ Ummmm "designing a PCB online?" Why use some wishy washy web majiggy instead of a real design program? \$\endgroup\$
    – JRE
    Jan 14, 2018 at 18:04
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    \$\begingroup\$ @JRE: the web one is already installed and runs on linux/chromeos/mac/etc... \$\endgroup\$
    – dandavis
    Jan 14, 2018 at 22:08
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    \$\begingroup\$ ... having said that, I'm closing the question as too broad. For future reference, see this meta post: Why is “Is it possible to…” a poorly worded question? \$\endgroup\$ Jan 15, 2018 at 0:56

3 Answers 3

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Sure, I do it all the time — custom hubs for embedded applications. I use chips from Cypress, but they're certainly not the only game in town.

You do need to pay careful attention to the layout of the traces associated with the crystal and the USB data pairs (impedance-controlled). And some chips have a thermal pad that's difficult to solder without hot-air tools.

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  • \$\begingroup\$ Actually, you can get a "hot air rework station" marketed as "858D" for under $30 on e-Bay. Works just fine. \$\endgroup\$ Jan 15, 2018 at 2:01
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With some usb hub ICs it's as simple as the ic, a crystal, and a few passive components. Easy to design if you feel like taking the time. A single sided PCB is possible too.

Here's a simple (two-sided) example PCB:

4 port USB hub PCB

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    \$\begingroup\$ That's not a single sided PCB. It may have all of the signal traces on the top, but there are plenty of vias evident and no evidence of distributing both VBus and ground to the port connectors on the top layer. If there were, we'd see distinct traces on each side of those mounting holes in between the connectors, instead of one big copper pour. \$\endgroup\$ Jan 14, 2018 at 17:58
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    \$\begingroup\$ Well, how do you think they're getting both 5v and ground to all those connectors? And why do you think the upper trace from that multilayer ceramic near the UC5 label terminates at a hole in the PCB? It does seem like the IC has been designed to permit a very clean routing of the signals and perhaps the back is all ground or power plane - but it's not single sided. \$\endgroup\$ Jan 14, 2018 at 19:39
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    \$\begingroup\$ @Passerby What IC did you use for this? \$\endgroup\$
    – skillz21
    Jan 15, 2018 at 2:24
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    \$\begingroup\$ DIY 4 port USB Hub, hand-carved single-sided PCB! \$\endgroup\$ Jan 15, 2018 at 4:03
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    \$\begingroup\$ @Passerby He's not saying that it's impossible to do it on one sided board. He's saying that the image you have in your answer is double sided, which you are implying is single sided. \$\endgroup\$ Jan 15, 2018 at 17:22
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I have done this using TUSB4041I but had to use a professional assembly house to populate the board, it is incredibly fiddly.

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  • \$\begingroup\$ These chips are entirely within the range of careful hand work. A microscope will be a help, but it's possible to do it with only a 10x jeweler's loupe for post inspection. The key is to solder just one corner, check alignment, solder the opposite corner, check again, etc. You can also cut a thin strip of tape and put it diagonally across the chip to help with those first two pins. \$\endgroup\$ Jan 14, 2018 at 18:00
  • \$\begingroup\$ Yes i agree some can do it. That design had many discrete components as well though, 0603 size. At my age though hand steadiness is a major problem. \$\endgroup\$
    – beerbug
    Jan 14, 2018 at 19:19
  • \$\begingroup\$ It was a one off and was assembled by hand but by someone more dexterous than I with a few helping gadgets. \$\endgroup\$
    – beerbug
    Jan 14, 2018 at 22:20

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