Other Are all USB cables created equal?

I think Spec is (quite correctly) arguing that a USB cable which can't supply the correct signals cannot be classed as a USB cable. Unfortunately, to the average buyer if it says USB on the box they will assume it will work, whereas the reality is that some cheapo knock-offs seem to have everything in the right places but don't actually fulfil the USB standard.

 

Right. If you expect a product of 80 pence to be perfect you might be dissapointed. That said, once you get beyond a reasonable level whereunder they are required to skimp on the very basics of the product, any further expense becomes unnecessary.

 

Yep the digital signal is obviously there or not which is why I always buy the cheapest digital cables I can, this has convinced me to go a little bit more expensive if I'm charging something from the cable

 

So in other words, everyone on this thread is in agreement (even if they may not have realised it) and the conclusion is:

Are all USB cables created equal? No
The ones that conform to USB standard are all equal in performance
But there are some around that fail the USB standard although still being sold as USB cables, and these (in most cases) refuse to perform at the level required.

amirite?

(assuming "USB cable" is defined as anything being sold that says it is a USB cable)

 

While I'd agree with this, I would say that these cables are definitionally faulty. That is, if you buy a USB cable which is in any way inferior to any functioning USB cable, it is faulty and should be returned. That is to say, you can not have a cable which doesn't conform to the USB standard which isn't faulty.

 

Gottit, should have said there are faulty cables being sold masquerading as USB certified.

 

Well, there are faulty cables, yes. There are not specific types of USB cable in which all will be faulty, but the lower the price the more likely one is to find a faulty cable. Some cables may be made with such low standards that a high proportion of them are faulty.

I'm just trying to make it clear that there is never a difference in quality between different types of functioning USB cables, they are functionally identical so long as the are not faulty.

 

or use the one supplied with your phone?

 

It's a case of DON'T spend a fortune on a gold plated / shielded / shiny braided USB cable you gain nothing.....

But at least try and make sure the ones you do buy are from a company with at least a reasonable level of Q.C. (price is always a good example (if it's to cheap to be true.......))

As stated earlier both those cables worked for Devices attached to PC's it was only for charging that we could see a massive difference and that was due to the poor contact the pins/plugs where making.

Lesson to be learned is buy an OK USB lead (nothing more & nothing less) the build quality difference between £1 & £5 was massive. you will not gain anything more by spending more (other than a pretty colour).

As for someone asking about HDMI similar rules apply. As long as the cable & socket/pins are electrically sound and making a good conductive circuit it will work. the only time more shielding would be needed is in electrically noisy environments and "very" long runs.

And yes I have had disagreements with "digital audio" types as well, as long as signal to noise ratio is low your good to go.

 

Having thought about it HDMI doesn't provide power so yeah cheapest would probably be fine. I like the way all HDMI cables are now coloured gold on the connectors whether they are gold or not.

I've had endless discussions with my dad about spending £50 on an HDMI cable and in the end I've given up. He still thinks of everything in Hi-Fi seperates terms

 

such helpfulness deserves much gratitude

 

why didnt you use the one that came in the box?

 

I did use it, I have used it, I am using it, I need another one.

 

What I would really like to see is a load like a resistor put on the power lines and a current reading taken for each cable. Just to see what the real difference is. Looking through the standard if a micro connector is connected at any point the minimum current carrying capacity is 3A. If your cable can't handle a 1 amp power adapter then its unlikely it meets the standard.

Edit: Actually the standard might be as low as 1A for micro usb. Its a fairly large group of documents its hard to pick out just one detail.

 

Ok testing done with 1Amp supply & 3.3k Load resister (measurements taken as 1.00 amperes)

Method used: (USB Micro end removed) (1 Amp supplied via Mains to usb plug)



Cheaper £1 cable


£5 cable


Charging ports exist in two flavors: charging downstream ports (CDP), supporting data transfers as well (docking stations etc), and dedicated charging ports (DCP), without data support (USB Mains adapters). A portable device can recognize the type of USB port from the way the D+ and D- pins are connected. For example, on a dedicated charging port, the D+ and D- pins are shorted. With charging downstream ports, current passing through the thin ground wire may interfere with high-speed data signals. Therefore, current draw may not exceed 900 mA during high-speed data transfer. A dedicated charge port may have a rated current between 0.5 and 1.5 A. There is no upper limit for the rated current of a charging downstream port, as long as the connector can handle the current (standard USB 2.0 A-connectors are rated at 1.5 A).

Please note that most standard computers deliver around 500mA through the USB as a max as per USB 2.0 standard.