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can i ground pin 4 on a usb micro to make a cable compatible? Answered

some of the usb micro cables i have for my solar cell battery don't work, but when i plug in the usb female adapter and use the usb cable i use for my computer, my droid x charges just fine. being the way i am, i had to know what was going on, so i got an old bluetooth headset and desoldered the female usb micro plug and put some leads on it. then i plugged the cables in and tested continuity and i found out that the cable that works had pin 4 connected to pin 5, but the one that didn't work had no internal connections at all. i find the position the cable sticks out when it's plugged in kind of annoying, so i might be able to kill 2 birds with one stone by making a small extender with pins 4 and 5 connected and just leaving the extender connected all the time or would my dx detect that pin 4 and 5 are connected without a voltage and cause problems? i would really like to just make this, plug it in, and not have to worry about cables not working or getting in the way, but i don't want to test this on my $600 device when i don't know what might go wrong.


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9 years ago

Does your solar cell battery talk to the droid at all? or does it simply provide power over the USB power pins?

I didn't even know micro USB had 5 pins, thought they all only had 4.

A link or product name for the solar cell battery would help


Answer 9 years ago

So apparently (yay wiki) the 5th pin (pin #4) is to distinguish between micro-A and micro-B connectors.
Its either wired to ground, or not wired at all.

judging by (http://en.wikipedia.org/wiki/Universal_Serial_Bus#Physical_appearance) you have a micro-B when you need A.


I'm guessing you used a full sized USB cable with your female adapter? those only have 4pins, so your adapter wired pin5 to pin4.

so if you make some sort of extender plug or whatnot, as long as you only change pin 4 or ground and leave the other pins (like D+/-) you should be fine.