cable questions - "fast charge" from laptop USB & what makes a "data cable"?

[Tinytacohead]

Awhile back I bumped into what I think was some special cable and/or change you could make that'd allow regular speed/faster than typical charge speeds from a laptop USB. Am I talking outta my ass, or is such a thing possible, and if so how?

Also, what actually makes the difference between a "data" and regular USB cable, if anything? As always, thanks in advance!

 

[Mikestony]

Well, I do know that the "fastcharge" option, at least for me, requires a kernel that supports it. With that said, you would have to be rooted to change kernels.
For example, I can charge from my laptop usb port as if it was plugged into the wall...a full 1 amp vs. .5 amp (normally from the usb port).
So yes, your question is a very good one and you are not talking out of your ass lol

As far as the cable question, I do believe there are charge only cables and charge/data cables...that's about all I know One has an extra pin in them to allow data I believe.

Someone who knows more about that than me may chime in

 

[Tinytacohead]

Thanks for the info, at least now I've got some direction! As for rooting, I tried a few times last year & when I was unsuccessful, decided to make a post about it. The dude who did the write-up I was following basically made me feel like a moron, (and didn't answer my question, heh), so I gave up for the time being. Perhaps next time will be different though. I really don't understand why phone devs make us jump through such hoops just to charge at a decent rate without an outlet?!

 

[Mikestony]

Well, I hope you have a better experience rooting next time...what device do you have (curious)?
I want to say, and I could be wrong, that some Nexus devices (maybe tablets) charge at a faster rate out of the box...not sure tho :dontknow:

The only drawback for me with the fastcharge option, is when activated, the computer won't recognize the device.....i.e. cannot move files/see files/edit files on the phone with the computer. But hey, I can live with that

 

[Tinytacohead]

Thanks, Galaxy S4 here. (dunno why my sig's not showing all of a sudden, tho it did in my first reply & is still set to do so)

 

[Mikestony]

Thanks, Galaxy S4 here. (dunno why my sig's not showing all of a sudden, tho it did in my first reply & is still set to do so)

Oh, I missed that And your signature will only show once per page, so it's not you, its us lol

 

[Tinytacohead]

Interesting, and thanks for the clarification!

 

[twister6]

I remember seeing something like this advertised. Now, think about. USB 2.0 can only provide 500mA and due to efficiency loses it will be closer to 400mA. USB3.0 stepped up to 900mA, but it has to be enable from bios of your PC/laptop to work as "power" port (depending on mobo). Anybody who claims they can up-convert current source to double it or whatever, are using an active circuit to boost it through some low impedance path which is all questionable. Why go through all this hassle when you can just use a standard 2A wall charger?

Look into the list of all of my reviews (link in the signature or the stickyin this forum), and get yourself one of those 40W (5-port 8A) Anker wall usb chargers. It provides a total of 8A from 5 ports, and each port has a smart features to charge any android or apple device up to 2.4A (like the latest iPad). Don't mess with any active conversion circuits running off your laptop usb port, you don't want to fry your mobo and/or damage the phone.

 

[Mikestony]

I remember seeing something like this advertised. Now, think about. USB 2.0 can only provide 500mA and due to efficiency loses it will be closer to 400mA. USB3.0 stepped up to 900mA, but it has to be enable from bios of your PC/laptop to work as "power" port (depending on mobo). Anybody who claims they can up-convert current source to double it or whatever, are using an active circuit to boost it through some low impedance path which is all questionable. Why go through all this hassle when you can just use a standard 2A wall charger?

I'm curious How then can my device draw 1 amp from the usb 2.0 port on my computer if the port is limited to .5 amp?

Look into the list of all of my reviews (link in the signature or the stickyin this forum), and get yourself one of those 40W (5-port 8A) Anker wall usb chargers. It provides a total of 8A from 5 ports, and each port has a smart features to charge any android or apple device up to 2.4A (like the latest iPad). Don't mess with any active conversion circuits running off your laptop usb port, you don't want to fry your mobo and/or damage the phone.

Curious again, and yes I am misinformed sometimes , but won't the device only draw what it's designed to draw? i.e., device "X" will only draw 2 amps no matter if it is connected to an 8 amp charger.
I think of it like this, the starter on a truck will draw, lets say 200 amps...it won't draw any more amps even if I connect 4 batteries to it each with 950 amps.
Perhaps my thinking is off kilter

@Tinytacohead, if my post is derailing your thread, I'll delete it...no worries

 

[twister6]

Mike, you are absolutely right. That wall charger I mentioned can source up to 2.4A per port for a total of 8A simultaneously across all 5 ports, but your phone/tablet will draw only as much as it required at max charging speed. So connecting S4 or N2 will draw 2A, while connecting Nexus 7 (2012) will draw only 1A and Nexus 7 (2013) will draw 1.5A, or the latest iPad will draw 2.4A. It's the same with most of the wall or car chargers. Their max rating means how much they car source from a port, while your device will draw current at it's own max speed.

With your computer usb port, they gotta be playing with conversion numbers. If you know you can provide 5V @ 0.5A, that's 2.5W (P=V*I). By Ohm's law, V=R*I, so P=R*I^2. I have no idea what regulators and converters they use, but those are the only variables you can play with. If you increase I, you will have to decrease R in order to maintain 5V output and the same power out of the port. That's why I mentioned they could have low impedance path (low resistance) to increase the current. Of course, you can also use transistor circuit as current amplifier.

Again, all this is a theory and a basic EE101 I have no idea what they are doing inside. Maybe they need to use 2 usb ports to combine current, who knows. Or maybe they use a simple transistor circuit to amplify the current? I just would be very careful with such claims.

 

[Tinytacohead]

..Why go through all this hassle when you can just use a standard 2A wall charger? ..

Because when at my desk my phone sits on its cradle, plugged into my PC. (as I've got quite a few more open USB slots than wall outlets + it's always ready for a direct file transfer) When traveling, the less charger's I've gotta keep track of the better. Due to that & the fact that I've always got my laptop at such times, I'd prefer to simply charge off of it as well. (and usually do, sloowly)

Just had a thought.. I've got 3.0 slots available on either system. (which are enabled for power whatever) If I had a 3.0 cable going to the phone, would it charge any faster? Currently it makes absolutely no difference to charge times, whether it's plugged into 2.0 or 3.0.

Mikestony, no worries.

 

[twister6]

One of the solutions in your case might be this Anker USB 3.0 4-Port Hub with 5V / 2.1A Charging Port

I did a review of this one as well. You get 4port USB 3.0 hub and another charging port. You will have to switch cables but at least you are dealing with one small compact gadget

 

[Mikestony]

Mike, you are absolutely right. That wall charger I mentioned can source up to 2.4A per port for a total of 8A simultaneously across all 5 ports, but your phone/tablet will draw only as much as it required at max charging speed. So connecting S4 or N2 will draw 2A, while connecting Nexus 7 (2012) will draw only 1A and Nexus 7 (2013) will draw 1.5A, or the latest iPad will draw 2.4A. It's the same with most of the wall or car chargers. Their max rating means how much they car source from a port, while your device will draw current at it's own max speed.

With your computer usb port, they gotta be playing with conversion numbers. If you know you can provide 5V @ 0.5A, that's 2.5W (P=V*I). By Ohm's law, V=R*I, so P=R*I^2. I have no idea what regulators and converters they use, but those are the only variables you can play with. If you increase I, you will have to decrease R in order to maintain 5V output and the same power out of the port. That's why I mentioned they could have low impedance path (low resistance) to increase the current. Of course, you can also use transistor circuit as current amplifier.

Again, all this is a theory and a basic EE101 I have no idea what they are doing inside. Maybe they need to use 2 usb ports to combine current, who knows. Or maybe they use a simple transistor circuit to amplify the current? I just would be very careful with such claims.

Nice! Thanks twister (most of that goes over my head lol)
I think the fact my kernel for my phone is responsible for the 1 amp draw from the usb port...it supports fastcharge. I have no idea how it does it, but it sure is nice at work for me.

 

[twister6]

Nice! Thanks twister (most of that goes over my head lol)
I think the fact my kernel for my phone is responsible for the 1 amp draw from the usb port...it supports fastcharge. I have no idea how it does it, but it sure is nice at work for me.

Hmm, that's interesting. The kernel for your phone has the ability to enable fast charging and that makes perfect sense. But I'm a bit puzzled how you are able to draw 1A of current from a typical PC/laptop usb port. Just curious, how do you monitor this amount of current? Is there a util (for rooted) that can do that? There is a free app Galaxy Charging Current, but its only for Galaxy phones Note 2, S4, Note 3, and up. Another way, since you know the exact capacity of your stock battery, you can time it to verify it. For example, if you start with 50% capacity from stock 2100 mAh and it takes your 1h to charge to 100%, you know the charging speed is (1/2 * 2100 mAh) / 1h = 1050 mA => 1A. Or you can use one of these tools (probably can get it on ebay for $3-$4 now) I reviewed here: http://androidforums.com/samsung-ga...r-charging-your-phone-tablet-w-lots-pics.html - there is a small marginal error since it uses a little bit of current to power up itself, but it's actually a very neat tool to get some ballpark numbers when you are troubleshooting your usb cables or chargers. Comes very handy for relative measurements if you want to find the fastest charging combo among your cables and wall chargers

 

[Mikestony]

Hmm, that's interesting. The kernel for your phone has the ability to enable fast charging and that makes perfect sense. But I'm a bit puzzled how you are able to draw 1A of current from a typical PC/laptop usb port. Just curious, how do you monitor this amount of current? Is there a util (for rooted) that can do that? There is a free app Galaxy Charging Current, but its only for Galaxy phones Note 2, S4, Note 3, and up. Another way, since you know the exact capacity of your stock battery, you can time it to verify it. For example, if you start with 50% capacity from stock 2100 mAh and it takes your 1h to charge to 100%, you know the charging speed is (1/2 * 2100 mAh) / 1h = 1050 mA => 1A. Or you can use one of these tools (probably can get it on ebay for $3-$4 now) I reviewed here: http://androidforums.com/samsung-ga...r-charging-your-phone-tablet-w-lots-pics.html - there is a small marginal error since it uses a little bit of current to power up itself, but it's actually a very neat tool to get some ballpark numbers when you are troubleshooting your usb cables or chargers. Comes very handy for relative measurements if you want to find the fastest charging combo among your cables and wall chargers

I use BatteryMonitor Widget Pro to monitor the charge/discharge in maH.

I could post back here the screenshot later of the fastcharge option "on" when plugged into the computer. I do have the 2100maH battery in my S3.

I'll check out that tool you reviewed...that looks cool

 

[twister6]

I just realized I have BatteryMonitor Widget Pro as well! Totally forgot about it, will have to play around with it again

 

[Tinytacohead]

One of the solutions in your case might be this Anker USB 3.0 4-Port Hub with 5V / 2.1A Charging Port..

Interesting/possibly something I'll buy, thanks. I'm still curious though.. should my S4 be charging faster off 3.0 than 2.0, and if so/since it's not, why? (IE - do I need a 3.0 cable or something)

The whole kernel option is quite interesting as well, (since I wouldn't need to pack around any extra gadgets), though since I'm not yet rooted/before I go down that road, I'd like to hear about the above first..