Comment by analog31 | Hacker News Reader

Comment by analog31 | Hacker News Reader

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What I've read is that the Micro-USB plug is intentionally designed to fail before the connector inside the device is damaged.

I have a compulsion for fixing things, so I've seen a lot of gadgets where a connector has been broken away from a circuit board due to repetitive stress on a plug. The most common have been audio plugs -- headphone jacks in cellphones, and some connectors in musical instrument gear. I'd much prefer to replace a $5 cable than an expensive phone or gadget.

But of course it's arguable that they made it too delicate.

Now that I'm on my soap box... I've also seen a lot of damaged cables where the breakage is in the wire just as it exits one of the plugs. And a common cause is the habit of coiling your cables neatly by wrapping them as tightly as possible. Since I mentioned musical gear, I'm a working musician, and I cringe when I see how people -- even engineers -- treat cables. I always advise people to watch one or two of the ubiquitous videos where some burly roadie shows the proper way of coiling and handling a cable. I'm a bassist, and I have cables that have lasted 20+ years.

> the Micro-USB plug is intentionally designed to fail before the connector inside the device is damaged.

I've had two devices where the MicroUSB socket has broken off the PCB. Not a huge amount considering I've probably had tens of devices with MicroUSB power over the years but a truly inconvenient amount given the impossibility of a home fix (for most people.)

Now I use those magnetic-plug cables and just leave the MicroUSB ends in whatever I might need to charge to avoid the physical stress.

That's a different failure mode. Before Micro USB there was Mini USB, which was the same concept but I believe the fault was that the springy parts were inside the device. When that wore out, you were screwed because the cable would just cease to make good contact, and a new cable wouldn't help.

Micro USB's improvement was reversing where the weak bits were. Now it's the cable that wears out, so when it does you just throw it out and buy a new one.

Attachment to the board is another thing entirely, it's all about having some sort of through hole pins to hold it in place (not all devices had that, some were purely surface mount), and good design. I think some devices had a tiny daughter board for the connector, to ensure that part could wiggle around a bit for stress relief.

The Mini USB plug layout also gives it more leverage to apply force to the PCB connections. It's a really annoyingly bad design.

I think Nokia's original Micro USB socket design had only two through-hole pins, which was not sturdy enough.

A standard USB-C socket has four: one in each corner like some later Micro USB sockets. There even exists USB-C sockets with all through-hole pins but there's no space for USB 3 pins so they are all USB 2.0 or charging-only.

I used to buy cables with non-standard reversible Micro USB plugs, but I think there was only one manufacturer of them and now I can't find replacements.

A large part of it is basic physics. A Micro-B connector like [0] is way easier to damage than a C connector like [1] because it is less solidly mounted to the PCB, and because it has a shorter distance from the fulcrum to the furthest mounting point.

I have accidentally ripped off Micro-B connectors, but ripping off a C one usually requires a nontrivial amount of force.

[0]: https://www.lcsc.com/datasheet/C53207153.pdf

[1]: https://www.lcsc.com/datasheet/C53431229.pdf

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