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When buying electronic products that use a microUSB plug for powering, we often receive a male USB <--> male micro USB charging cable that doesn't include the 2 DATA lines (Data + / Data -).

It's extremely annoying for the end-consumer, because :

  • at the end you have a big amount of USB-µUSB cables at home that you cannot distinguish visually (no distinctive symbol on the cable): some of them are "power only" (won't work to transfer files from phone to computer for example), some others "power+data" (will work for file transfer).

  • it can lead to ambiguous situations like "My device X doesn't work anymore. I plugged it to my computer and it's not recognized as an USB device". In fact it's just that the cable is not a real USB cable, but only a charging cable.

Question: Is there an electronic justification to produce micro-USB to USB cables that don't include the data lines, except for saving 0.00001$ per cable for the maker because they can avoid 4 soldering points for the soldering robot?

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closed as off-topic by Enric Blanco, Voltage Spike, Andrew, The Photon, uint128_t May 3 '17 at 15:15

  • This question does not appear to be about electronics design within the scope defined in the help center.
If this question can be reworded to fit the rules in the help center, please edit the question.

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    \$\begingroup\$ Why would a manufacturer need more reason than to save some money? \$\endgroup\$ – PlasmaHH May 3 '17 at 12:25
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    \$\begingroup\$ If they can make more money, why would they care about whether the user like it or not? Nobody will base their buying decisions on the type of cable that comes with the device. Also note that per gram copper you save ~.5¢ \$\endgroup\$ – PlasmaHH May 3 '17 at 12:29
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    \$\begingroup\$ Margins are tiny in mass-produced commodity products like this. That's also why the cable is so short. \$\endgroup\$ – pjc50 May 3 '17 at 13:02
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    \$\begingroup\$ I've already got tape on my micro and mini cables to distinguish them without having to look too hard, another different colour for non-data micro would work. \$\endgroup\$ – Neil_UK May 3 '17 at 13:03
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    \$\begingroup\$ I'm voting to close this question as off-topic because we're not here to hear rants about cost cutting practices. \$\endgroup\$ – Enric Blanco May 3 '17 at 13:33
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No. They're not USB compliant.

They're not even allowed to carry the USB logo.

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  • \$\begingroup\$ Op did not ask about compliance. \$\endgroup\$ – Passerby May 3 '17 at 15:45
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    \$\begingroup\$ @Passerby, If not compliant, they shouldn't have the logo. Without the logo (or with an alternate logo) they could be visually distinguished from compliant cables. And how to visually distinguish these cables is a large part of OP's question. \$\endgroup\$ – The Photon May 3 '17 at 15:54
  • \$\begingroup\$ Arguably they are not a "USB cable". They may be a semi-functional counterfeit if they bear the logo. \$\endgroup\$ – Spehro Pefhany May 3 '17 at 20:31
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One reason to omit the data lines is to make a "charge only" cable. Using such a cable when charging your devices on a public USB port or charging via an unknown computer assures that no hacking attempts may be made through the USB port while the device is charging.

There are devices that are marketed as "USB condoms" to provide the same function.

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The answer is NO. There is no electronic reason. Just cost.

Never underestimate cost... If it only saves 5¢, when you sell a million of them, that's $50,000 you didn't need to spend.

Yes it can be irritating, but a lot less irritating that the former state of the art of having a box full of wall warts, all different voltages and AC and DC with different jack plug configurations on each, and never the one you needed.

Though, you are right, it would be nice if they changed the symbol on the power ones so you could tell by looking. Though as someone else mentioned, it should not have the logo if it is not a full USB cable.

ADDITION: There may also be a limiting liability reason. The manufacturer may not want the headache of dealing with accepting the signals from whatever the cable is attached to.

i.e. Complaint calls of.. "When I plugged your gizmo into the port on my computer, the screen went blank and smoke came out..." or "After I used your cable to recharge the gizmo, my USB port will no longer talk to my hard drive.."

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