What makes a good high current micro-usb cable?

[Kenneth Tan]

I've recently bought 10 micro-usb cables. Tested them and all charged my Galaxy S4 @ 920mA. (Very nice)

The cables had two problems. After a while the cable broke, just a centimeter from the microusb connector.
I have ordered some new solder micro-usb connectors from China through ebay.
After replacing them on the cable, the charge current decreased to 460mA. (Almost exactly half)

Only two wires (black & Red) were connected in my replacement, in the original setup all 4 were connected.

Any idea why the charging current is halved?

 

[Gryd3]

I've recently bought 10 micro-usb cables. Tested them and all charged my Galaxy S4 @ 920mA. (Very nice)

The cables had two problems. After a while the cable broke, just a centimeter from the microusb connector.
I have ordered some new solder micro-usb connectors from China through ebay.
After replacing them on the cable, the charge current decreased to 460mA. (Almost exactly half)

Only two wires (black & Red) were connected in my replacement, in the original setup all 4 were connected.

Any idea why the charging current is halved?

USB charging specifications dictate how much current is drawn by a device.
Because the replacement only has the power wires and not the data wires, your device and charger cannot communicate to be able to allow charging with more current. It's imperative that any high current charging applications use the signal wire pair to communicate with the charger to be able to take more than 500mA.

 

[Kenneth Tan]

Thanks for the quick reply.
A Google search for 'USB charging specifications" got me the result I needed.
http://www.maximintegrated.com/en/app-notes/index.mvp/id/4803

if I'm correct in interpreting the text, I should short D+ and D- for maximum charge current.
The USB interface in the phone should test this circuit (resistance to short) to what chargestate it should function.
I will make a short in the connector and report the results.

 

[Gryd3]

Thanks for the quick reply.
A Google search for 'USB charging specifications" got me the result I needed.
http://www.maximintegrated.com/en/app-notes/index.mvp/id/4803

if I'm correct in interpreting the text, I should short D+ and D- for maximum charge current.
The USB interface in the phone should test this circuit (resistance to short) to what chargestate it should function.
I will make a short in the connector and report the results.

That is not always a 'standard' that is followed.
If not a short, some devices require a resistor, or voltage divider to be in place on the D+ and D- lines.
You seem resourceful though finishing up the answer by doing your own research, so I thank you for that and wish you the best of luck in making it work for you.

 

[Kenneth Tan]

Looks like I have to short the data leads together and connect them to a 2x 82kOhm voltage divider bridge to tell the Samsung S4 to charge @1.3 Amps.
http://forum.xda-developers.com/showthread.php?t=2274321

 

[Gryd3]

Looks like I have to short the data leads together and connect them to a 2x 82kOhm voltage divider bridge to tell the Samsung S4 to charge @1.3 Amps.
http://forum.xda-developers.com/showthread.php?t=2274321

Like I said. Resourceful.

 

[hevans1944]

Like I said. Resourceful.

We like that here at Electronics Point!

 

[Kenneth Tan]

And here are my results:
Only Vcc and Gnd to Galaxy S4: 460mA
As above, but with D+ & D- shorted (on phone side) : 1100 mA
As above, but with 2x 100K resistors between Vcc an GND + D-Short to the middle of the resistors: 1100mA (I did not have 82K resistors)

Current ratings are averages.

So in the end it only needed a short between the data points on the connector. Thats good, because it would have been a heck of a job to squeeze two 1/4W resistors into that small connector housing.

Case closed.

 

[Gryd3]

And here are my results:
Only Vcc and Gnd to Galaxy S4: 460mA
As above, but with D+ & D- shorted (on phone side) : 1100 mA
As above, but with 2x 100K resistors between Vcc an GND + D-Short to the middle of the resistors: 1100mA (I did not have 82K resistors)

Current ratings are averages.

So in the end it only needed a short between the data points on the connector. Thats good, because it would have been a heck of a job to squeeze two 1/4W resistors into that small connector housing.

Case closed.

Thank you for the update, and welcome to Electronics Point!
I hope to see you around here more often.