Hacker News new | ask | show | jobs
by eigencoder 14 days ago
I don't like USB-C because they all look the same on the outside, but they're not all the same on the inside. Especially my cheap consumer electronics. Sometimes they will charge, sometimes they won't charge, but all the cables look the same, and you don't tend to know in advance.
13 comments

If switching to a type-A charger fixes it, it’s probably the device manufacturer’s fault, not the cable. Many manufacturers that need the 5v standard you’d normally get from an old type-A charger screw this up.

For universal USB-C power support that works with modern power bricks, you need to tie 5k resistors to two pins of the port on the device. This tells the charger to use 5v. I can’t tell you how much cheap stuff out there omits these. They cost almost nothing but they still screw this up over and over, and people blame the standard or the cable…

I know of something expensive that omits it too! My insulin pump controller is a junkpile android phone (a NUU Mobile N5004L for the curious) whose only purpose in life is to run a singular android app.

The device charges via usb-c, but refuses to do so if the charger is any relatively modern usb-c based brick. Only usb-a!

Ugh, that’s infuriating to read, if not at all surprising. This sounds at once totally over-engineered (in the modern day, negative sense of the word) while being simultaneously under-engineered (in the traditional sense).
It’s definitely a weird scenario.

It seems everyone in the Durable Medical Equipment space for diabetes stuff just wants everything to be a smartphone app now- which is fine honestly, it’s convenient for those that want to use it, but I’ve been informed that many manufacturers (at least a good number of Continuous Glucose Monitor makers) have completely forgone native controllers these days. Omnipod just seems to have said “we’ll make one program because maintaining two could be problematic for consistency (and probably certification) reasons”, and then made the logical-enough extrapolation that their native controller can just be an android device. They just chose a cheap/shit one- which is fair! It runs AN app! But it also means I have to keep USB A to C chargers on me 24/7 :/

I’m just glad they at least do that, as smartphone-only options are problematic for a number of reasons, among them being the lack of ability to bring them into restricted areas. I hadn’t thought about it before, but it’d also be a problem for events where they use those stupid yondr bags, or even schools that use them now.

I guess you could just get your own little junkpile android for the sole purpose of being a controller, but still. sigh

I don't think it's cost reasons these are being omitted. The customer refunds would easily exceed the savings. It's most likely designers just swapping a micro usb port with a usb c one in an old design while making no other changes and seeing it works with the A to C cable they have.
I share your theory about micro usb, yeah. I know it’s not cost savings, it’s just lazy/ignorant. If they’re changing the footprint on the board for a type-c port, they can add some smd resistors.
This is really only a problem if you buy cheap cables. Pick the baseline spec you want your USB cables to meet, and throw out all the ones that don’t. Problem solved.

It’s still a minor frustration if you have to borrow a cable, but that’s solved by packing a cable, and by encouraging as many other people as possible to also throw out their cheap cables.

Sometimes it's not the cable. Sometimes it's the sodding device. I have some IP60-something speakers for the shower. Write up says USB-C power. Brilliant says I, I've got plenty of good ones I use for charging laptops and other USB-C form factor accepting devices.

Sodding things only charge with their special USB-A to USB-C cable. They're in the bag labeled "cursed usb-c charge cables".

I do electronics professionally. This is likely because in order to save a bit on BOM costs, the device itself doesn't have the necessary pulldown resistors to signal to turn on VBUS.

USB-A has always-on VBUS while USB-C doesn't. Because the spec allows for always-on VBUS in a USB-A to USB-C cable, some devices just assume that they're always being powered by one of those cables.

I doubt it’s even saving cost, it’s just incompetence. It works with the USB A to C cable, so job done. They’ve probably never plugged it into a PD charger, and probably just copied the schematic from the last (defective) product and will copy and paste it into the next one too.
That is likely the case; cost savings, simplicity, etc. but the end result is USB-C does not "just work" for most consumers.
It's because they are straight up defective. The USB-C spec is pretty clear in that the power pins have 0v until you signal for a voltage. This isn't a failure of USB-C, you should just return defective devices to the OEM.

Thankfully this defect is becoming less common outside of temu junk.

That's because they didn't implement USB C correctly. Maybe it was to save less than a penny on the BOM, maybe it was arrogance ("it works for me! send it!"), or maybe it was something else. Whatever the reason, they didn't do it right.

By standard, USB C provides no power at all unless the device being powered follows the rules. They're easy rules to follow. The minimum viable way of doing it right requires just two tiny resistors inside of the device.

It is not ideal, but you can buy C-to-C adapters with the resistors to force the charger to supply 5V.

https://www.aliexpress.com/item/1005012247371267.html

I have a water pump like that, the reason: they have omitted the 5.1k resistors…
you'll never guess what solution i'd suggest for that specific problem...
Change the device? It works fine. The cable is labeled. I know where to find it. I'm not throwing away perfectly otherwise-good hardware because of that.
If you want to cover all use cases your only option are the 240 W, 40 Gbps cables, and they are not cheap (https://www.amazon.com/Anker-Supports-Display-Transfer-Charg...).
amazon hides some prices because i'm viewing the page from canada, but it looks like that says the cable you linked is $15?

that's what i've been paying for cables, and it seems reasonable to me.

It's a cable, it should cost $2 at most.
40gbps is an insane data rate that requires shielding, precision, and testing. There is no way you are getting that for $2. That said, outside of connecting a laptop to your monitor, you don't need a 40gbps cable.
> 40gbps is an insane data rate that requires shielding, precision, and testing. There is no way you are getting that for $2.

I dunno, Cat8 is 40gbps and pretty cheap. DOCSIS 4.0 does 10Gbps on some really ancient cables. I'm sure Cat9 will do even better, at least the cat people and the doc people are trying harder than the USB people.

Unifi even has a PoE-over-coax solution. Add some Anker GaN shit and I'm sure it can be miniaturized.

> outside of connecting a laptop to your monitor

As soon as I need a "special" cable to connect a laptop to a monitor, we're effectively back to the 1990s-2000s when I needed a special monitor cable. There is no point to connector standardization if any cable can't do any function.

The whole point of this thread was "one type of cable for everything" and "grab any USB-C cable from your personal stash and they all work for every use case".

I have some Thunderbolt cables that are like $80 apiece because they're like 3 meters long. I have like five or six of them because each one only carries one video signal.

(I used Thunderbolt so that touch and pen inputs could go over the one cable. These days though I just use a MacBook Pro, and hook up a capture card when I need to access the Windows)

The apple usb c charging cable is like $30, it is well worth the money of you are into software defined radio I can report. Not sure what magic they pulled of, but all the tricks in the book it seems!
okay, i mean, that's exactly what my original comment said: this is only a problem if you buy cheap cables.
If some of your devices require a $30 cable and you use the same cables for everything, then you use a $30 cable for your mouse.
It's also only a problem if they overcomplicate power delivery design such that you need expensive cables.

They could have made it just DC +19V and GND over 14 gauge wire with a nice, outdoor-recreation-grade connector and called it a day.

> throw out all the ones that don’t

> encouraging as many other people as possible to also throw out their cheap cables

One of the main advantages of a single standardized plug is reducing e-waste. This just sounds irresponsible. Having a single tool that covers every possible use case is rarely a good solution.

Device makers need to stop including these garbage 4 cm A to C cables. I have enough USB cables and bricks to last my whole life. I don't need to collect a million more spec violating ones in a drawer I will never use.

Things are shifting though. Ikea ships their USB-C stuff without cables now.

> This just sounds irresponsible.

The irresponsibility lies with the companies making the non-compliant trash in the first place.

I have two different fast charging cables, for two different devices that charge fast with those cables, on those cables, but not if you swap them around. Thankfully they have different colors, so there's some hope of keeping track of which cable to use for which device.
There's no way to know if it's a "cheap cable", not even by price.
Sure there is. Buy reputable brands from reputable marketplaces that clearly state the specs, and if you get products from them that don't comply stop buying from them.
I'd call that trial and error.
I've been doing this strategy for years and never had an issue of buying a junk cable.

  Especially my cheap consumer electronics. Sometimes they will charge, sometimes they won't charge
This is not USB C's fault. It's the manufacturers who cheaped out a cent - or even less - on CC resistors.
on 0401 5k resistor is fractions of a penny. its just silly at this point. My belief is that they all used some crappy reference schematic which omitted it once upon a time, and that's proliferated amongst all the cheapo designs.
> Especially my cheap consumer electronics. Sometimes they will charge, sometimes they won't charge

You can fix that by buying USB-C to USB-C adapters with 5.1 kiloohm resistors.

It should have taken the manufacturer less than one cent to include the resistors, but as a consumer product they will unfortunately cost at least a dollar each.

Buy yourself a handful of good cable for charging. (I quite like the silicone anker 643) And throw everything else away in a box.

For data transfer you can just pick up one or two thunderbolt 5 rated cables, they will do max transfer for USB4, or any other spec in the near future. The LTT true spec cables are fairly priced but there are other big brands that sell the same thing.

Keep a shitty USB-A to C for those devices that do not have the correct pulldown resistor to support 5v 2a charging.

> I don't like USB-C because they all look the same on the outside, but they're not all the same on the inside.

Many people don't realize that USB-C (USB Type-C) just refers to the physical connector. At minimum, speed and power ratings should have been required for any cable using USB-C at one or both ends. It's almost breathtaking to consider how the USB Implementers Forum has fumbled these kinds of basic issues over the years.

USB-IF actually does have pretty clear labeling and standards that address most of the issues being posted in this thread. But most USB devices and cables are not certified and not compliant with the specs.

Short of making USB proprietary and behind a licensing and certification scheme there is no way to solve this. People need to stop buying cheap junk.

I read about this so often, yet it's a problem I just never encountered. If I need super high bandwidth like connecting a display, I pick one of those annoyingly unlflexible fat cables. Easy. They even tend to feature the TB4 flash icon. Surely I would not expect any of the light and nimble ones to do that trick. When I need strong PD, it's also either one of those or one of the far more flexible but still quite thick braided ones. Often they have some hinge gimmick connector to prevent any hope for bandwidth one might be tempted to have. All other cables, I expect nothing but legacy USB. Yeah, and some of those won't do data at all (curiosly those are never the lightest cables in my stable, the lightest ones tend to do the legacy USB "gear not, some bits will eventually get through!" just fine)
I wish there are easy ways to figure out the maximum current and wattage supported by a cable. So many cables don't label themselves except on the box!
Note there is a link at the end of the article to a device which can test cables and determine exactly that! But it's a sign of the problem that you need that thing.

With USB-C cables I tend to throw them out unless they are premium cables that cost upwards of $20, I mean I could keep the cheap ones around to charge this or that but cheap cables have this way of going bad, like they are supposed to work if you plug them in either way except they don't, you plug your cheap device in overnight to charge and it doesn't really charge, etc. No way I could trust my wife to handle it.

Personally I think USB got worse in a lot of ways in the 3.0 generation, like at 1.0 they designed a bus architecture that could enumerate 127 devices on a root hub. USB 3.0 doesn't promise anything and ff you start plugging in hubs to your laptop you will hit undocumented limits and find devices start dropping out randomly when you've plugged in several devices and it gives me the heebie jeebies because a mass storage device could drop out. I know mainstream filesytems today are pretty durable but still...

Even the simplest 3-wire cable with nothing but wires in it will handle 45W charging already, which is enough to power my laptop. It needs to be physically broken to not work. If it doesn't, it's usually the device's fault. There are many cheap devices out there that are just USB-C-shaped and don't actually implement the spec, working with some kinds of cables and not working with others.
Personally I have stopped buying cables that do not disclose this information. There are pretty fine alternatives that do, so I see no reason to take gambles.

My only issues so far come from charging protocols rather than cables anyway.

Moreover, stuff like how many watts a cable supports are issues that happen regardless connector type.

You're welcome: https://www.amazon.com/dp/B0DYJL5Z67

This device let me categorize all my loose cables (and throw out the truly terrible ones). It was worth every penny.

Not saying this device is not cool, but one can also get this info easily in a computer, if you find out what to look for. One had presented a utility here some time ago with a menu bar icon showing this information

https://news.ycombinator.com/item?id=47972511

If I remember correctly, that application/your computer is simply reading what the device _claims_ it can do whereas this device tests it.

That app is probably a good place to start but I wouldn't trust it fully.

These PD testers are cool (I thought about buying one), but honestly, for the price of a tester, one can buy 2, maybe even 3 good quality cables and just throw away the rest.
Fair point, I just have oodles of cables (literally 10-20+ per combo of micro/mini/standard-USB-A/B/C <-> micro/mini/standard-USB-A/B/C each) and I like having them all organized by capability so that when I need one I can grab from right bin.

Before getting the tester I just kept buying new "known good" cables whenever I needed one since my cable drawer was just a huge unknown.

> Reads eMarker chip parameters in Type-C cables, providing detailed performance information (e.g., maximum current, voltage, data transfer rates) to help users fully understand cable capabilities and ensure safe, efficient device usage.

Good thing nobody lies.

This is an acceptable failure mode. I'd be nice if there was a standardized LED flash or color that you could get so if your relative said something isn't working, you could ask, "Is it flashing three times?" or whatever.

The alternative is barrel connectors. If you plug in the wrong one, there's a decent chance that it a) won't work, or b) never work again.

> The alternative is barrel connectors. If you plug in the wrong one, there's a decent chance that it a) won't work, or b) never work again.

I remember my parents had a D-Link ADSL modem and a D-Link router. They even stacked onto of each other with rubber feet! They had identical-looking power bricks, with the same barrel plug.

They were different voltages!

And then you go someplace, realize you left your charger at home, and find out despite your friend having dozens of barrel type power connector power adapters not a single one match the size/voltage/amperage/polarity of your device.

Or you just borrow their USB-C adapter and don't have any worries.

The thickness / durability of the cable is a pretty good indicator, if it's thin and flexible it'll only do basic charging if it's thick and durable it's because it's packing enough wiring to do power delivery, video etc, everything except probably Thunderbolt.
All standards-adherent cables that are adorned with USB C connectors at each end can supply at least 60W of power.

This has nothing to do with feels.

Usually they won't charge because they're not actually USB-C devices but are just broken and only pretend to be one (mostly due to missing resistors on CC lines, but there are other ways a device can be non-compliant too).
Yeah I have some devices that expect the manufacturer charger (I guess it's pre-negotiated to 19V or something) and I'm not even sure what was the point in giving it a USB C connector.
I have a couple of devices that are 12V over usb-c. The devices themselves are fine, but the wallwarts the mffr provided are just that - 12v over usb-c. No PD. If a device is expecting 5V, there's a healthy chance it'll .. stop expecting 5V.

We blame usb-c for all this, but it does feel like some mffrs are going out of their way to screw it up.

Imagine if all USB-C cables had a patent owned by the consortium and an identification chip made by the consortium. The spec could require that devices would not use the cable at all unless the chip is cryptographically verified, and bad cable manufacturers could be sued into oblivion for breaking the patent.

The more I age, and the more I expect my devices to justwork™, the more I appreciate Apple’s pro consumer monopolistic moves.

>I guess it's pre-negotiated to 19V or something

This kind of defect is extremely rare since this would basically be a USB killer frying every other device you plug it in to. 99% of the time it's the device is missing some resistors on the cc pins which signal to the charger to send 5v. Since usb-c it defaults to 0v until you request something. But USB-A has no CC pins so it just puts 5v out at all times.

Yeah maybe USB-D will get it right. But probably not. I had such high hopes for USB-C. Now I keep a couple USB-C to USB-A adapters lying around to force the charger (which is just a normal home outlet with a couple built-in USB-C ports) to speak old school USB-A charging instead of trying to negotiate PD with a shitty device that did not implement USB-C correctly.

Yes that's the fault of the manufacturer. But the wildly flexible spec for USB-C let it happen.

It's not a flexible specification, its straight up bad engineering. The specification literally says if you do not want negotiation, you must add the resistor.
Unfortunately the EU has written USB-C into law, so there will never be a USB-D. I guess we should be glad they didn’t do this 30 years ago, or we’d still be using PS/2 connectors.
Law is not immutable. It will be changed if/when there is a need to.