Develop Bugs

[Q] Rapid Chargers - Not Really Rapid?

i bought that Motorola Rapid Car charger recent and have been using it about a week now. i've noticed that it doesn't seem to charge my Thunderbolt any faster then it did when i was using the Thunderbolt's USB cable with this USB car charger adapter.
so, my question is, why is it called "rapid" if it doesn't charge any faster?
and i suppose secondly, is there an actual microUSB charger that will charge the Thunderbolt faster?
they make one for the iphone that will fully charge it in 30 minutes so i know they are out there.

voxigenboy said:
i bought that Motorola Rapid Car charger recent and have been using it about a week now. i've noticed that it doesn't seem to charge my Thunderbolt any faster then it did when i was using the Thunderbolt's USB cable with this USB car charger adapter.
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Maybe you should try this one.

Install the battery monitor widget. Monitor the battery for about 20 minutes while charging. Tell us what the charge current is.
Does the Motorola charger include a cable? If not, you may just have a weak cable. I have seen cheap cables with wire so thin that the charging current is no better then charging off a weak USB port.

My experience has been that the phone typically recognizes car charges as USB charging and uses a different charging profile. My solution to that is use a wall charger through an inverter or a kernel that doesn't use radically different charging profiles for A/C and USB.

loonatik78 said:
My experience has been that the phone typically recognizes car charges as USB charging and uses a different charging profile. My solution to that is use a wall charger through an inverter or a kernel that doesn't use radically different charging profiles for A/C and USB.
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No need for that.
Cut a small piece of aluminum foil. Carefully place it where it shorts the two center conductors in the charger. Plug the USB cable into the charger. Make sure the foil stays in place over the two center conductors.
It is now a high rate charger. (assuming it can put out 1 amp.)

The limiting factor is typically the usb cable itself. Most usb cables can't support the 1amp that is provided to it. Since you used the original usb cable that came with the thunderbolt (that's been "shorted" as mentioned above" ) it will be just as fast as the moto car charger. the 1amp charging rate that the moto charger charges at (i have one) and that the original one charges at are already "rapid". if you plugged a normal usb cable from somewhere else into the other usb car charger, it'd be much much slower

squeakyl said:
The limiting factor is typically the usb cable itself. Most usb cables can't support the 1amp that is provided to it. Since you used the original usb cable that came with the thunderbolt (that's been "shorted" as mentioned above" ) it will be just as fast as the moto car charger. the 1amp charging rate that the moto charger charges at (i have one) and that the original one charges at are already "rapid". if you plugged a normal usb cable from somewhere else into the other usb car charger, it'd be much much slower
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The stock charger is what shorts the connections. The cable is NOT shorted on the two inner pins because they are the data connections used for connecting your phone to a computer.

doodlebro said:
The stock charger is what shorts the connections. The cable is NOT shorted on the two inner pins because they are the data connections used for connecting your phone to a computer.
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To meet the USB charging spec (which the TB uses), the two inner (data) contacts should be shorted with no more that 200 ohms.
But, the cable can also be an issue for rapid charging. The voltage drop for a 1A/5V source, across only .5 M of 28 gauge copper is ~220 mV. If you use a longer cable, there's more voltage drop. The TB likely current limits itself when the voltage drops below a certain threshold. Best to buy 24 gauge USB cables, if you can, especially if getting longer ones (monoprice has them).

voxigenboy said:
i bought that Motorola Rapid Car charger recent and have been using it about a week now. i've noticed that it doesn't seem to charge my Thunderbolt any faster then it did when i was using the Thunderbolt's USB cable with this USB car charger adapter.
so, my question is, why is it called "rapid" if it doesn't charge any faster?
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Click to collapse
I think its a matter of rated output current. BUT on the other side, the phone must be capable of drawing/using that much current. If the adapter is rated for more current than the phone can charge, the "extra" current wont be supplied.
Initially, Moto's standard car chargers output 5V and up to 550ma max (just like a standard PC USB port) so they didn't charge phones all that fast. Moto then came out with chargers that had higher current output, so they were capable of charging the phones "faster" than the original car chargers (but on par with the home/travel/AC chargers) and called them "rapid car chargers"..
Today, the current output on the Moto SPN5400A car charger is 0-950mA, and I've seen it sometimes referred to as "Rapid Car charger."
But as far as I know, Moto no longer makes/sells the lower current car chargers, and their web site only shows one MicroUSB and one MiniUSB car charger for sale, both of which appear to be of the 0-950mA output variety.
voxigenboy said:
and i suppose secondly, is there an actual microUSB charger that will charge the Thunderbolt faster?
they make one for the iphone that will fully charge it in 30 minutes so i know they are out there.
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Click to collapse
Just because someone makes such a charger for the iPhone, doesn't mean one must exist for the TB, or other phones, does it? I know the iPad uses a 2A charger. What happens if you connect an iPhone to that? will it charge faster? I guess that depends on if the iPhone is capable of drawing more than 1A to charge it.
I've not seen a "home" or AC charger that can charge the TB any faster than the Stock 1A charger. Does such a thing exist?
A proper car charger with 950mA to 1A output should charge the TB at almost exactly the same rate as the stock 1A wall/AC charger.
And btw, the Moto SPN5400A car charger DOES charge my TB in about the same amount of time that it takes me to charge my TB at home with the stock HTC charger. So while its not "rapid" compared to the stock home/travel/AC charger, its "rapid" compared to PC USB Port charging, or a plain lower current car charger.

KidJoe said:
I've not seen a "home" or AC charger that can charge the TB any faster than the Stock 1A charger. Does such a thing exist?
A proper car charger with 950mA to 1A output should charge the TB at almost exactly the same rate as the stock 1A wall/AC charger.
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I made a charger for my motorcycle. I use it as a GPS, screen on MAX, phone active with marginal signal. And I wanted to actually charge the battery at the same time. I did a lot of experimenting with the Thunderbolt. It would not exceed a pull of about 850ma from the supply, even at 5.5 volts. IMHO, you are wasting time looking for any charger over 1 amp.
Also, even with about 850ma in, not much over 500ma is getting to the battery. So a totally dead battery is still going to take between 2 and 3 hours to charge, no matter what charger you have. And twice that long if the charger looks like a PC USB port.

worwig said:
I made a charger for my motorcycle. I use it as a GPS, screen on MAX, phone active with marginal signal. And I wanted to actually charge the battery at the same time. I did a lot of experimenting with the Thunderbolt. It would not exceed a pull of about 850ma from the supply, even at 5.5 volts. IMHO, you are wasting time looking for any charger over 1 amp.
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I was asking because of the OP's statement about knowing "they must exist" because they are out there for the iPhone.
I'm perfectly happy with my Moto car charger, and how fast it charges my phones.

Automobile Quick Charging Solution

What is the best solution for quick charging the Galaxy Nexus in an automobile?

I have started to use 12-220 volt converter so I can use wall chargers.

I have bought a few of the low profile car usb chargers but they were never recognized as an AC charge. Come to find out, it was the USB cable. I bought a usb charging cable from Amazon last week and it goes in the USB charger and the phone does not think it is a USB charge. I have not timed it but it is recognized the same as the wall charger.
http://www.amazon.com/gp/product/B003VYBCAY

ellisz said:
I have bought a few of the low profile car usb chargers but they were never recognized as an AC charge. Come to find out, it was the USB cable. I bought a usb charging cable from Amazon last week and it goes in the USB charger and the phone does not think it is a USB charge. I have not timed it but it is recognized the same as the wall charger.
http://www.amazon.com/gp/product/B003VYBCAY
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+1 .. this solution has been working great for me, as well.

I've been getting 2.1A car chargers (look for ones for the iPad), most of the ones I had prior to this were 700mA or so and they can't keep up with my 1A phones. Be careful of dual port chargers advertising 2A, they may only be 1A each and may be "optimistic" about that rating. And don't worry about getting one rated for too much current, the Galaxy Nexus won't pull more than an amp no matter what the charger rating.

Some really good solutions here and thank you all for the help.
I'd really hate to use an inventer in my car just to maintain a clean install, so that really isnt an option for me.
Was really hoping to be able to use a off the shelf car charger with the correct pins to trick the GNexus into thinking that it was charging from a USB port, but the above solution should work well with using a socket USB charger.

I've never run into a car adapter that looks like a USB port, including the VZW charger with a spare port or the cheap 2.1A chargers I got from Amazon. My guess is that a charger not built correctly and leaving the data pins open only supports ~500mA anyway. Even if that's not the case I have a moral objection toward buying a cable to fix a design flaw in another cheap product - but that's just me

Grant H said:
Some really good solutions here and thank you all for the help.
I'd really hate to use an inventer in my car just to maintain a clean install, so that really isnt an option for me.
Was really hoping to be able to use a off the shelf car charger with the correct pins to trick the GNexus into thinking that it was charging from a USB port, but the above solution should work well with using a socket USB charger.
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I've got a charger similar to http://www.ebay.com.au/itm/USB-Car-...ccessories&hash=item4ab18358f4#ht_1638wt_1392
All I had to do was undo the screws at the top, put a bit of solder between the middle usb pins, and my phone recognises it as a AC source rather than USB.

There has got to be a standard car charger on the market with the middle usb pins already soldiered!
I found this on Amazon which advertises itself as a rapid charging device.
http://www.amazon.com/gp/product/B000S5Q9CA

Grant H said:
What is the best solution for quick charging the Galaxy Nexus in an automobile?
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Click to collapse
Make sure the charger has the IC (rapid) chip. I use this one:
http://www.amazon.com/Motorola-Vehicle-Adapter-micro-USB-Charger/dp/B000S5Q9CA

I've heard that Motorola one mentioned a lot as a good one.
The nice thing about having the low-profile usb plug is (a) it is low profile, (b) I can use it to charge other devices. The charge-only cable is only about $4, so I had no issues buying it to work with this to charge as an AC charge over a USB charge.

Grant H said:
There has got to be a standard car charger on the market with the middle usb pins already soldiered!
I found this on Amazon which advertises itself as a rapid charging device.
http://www.amazon.com/gp/product/B000S5Q9CA
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Click to collapse
I have this one and it charges just like it does from the home outlet and its says "AC" charging. I bought another 8 for family and friends and they all love it.

I think I've figured out the disconnect, I've run into chargers that appear as a USB host which limits the charging to 500mA on previous phones I've had.
You guys are concerned about USB vs. AC charging mode. Of the chargers I've got, this one lists as AC while the rest as USB. However, the fact that the other chargers all work just fine keeping up with GPS+streaming music indicates that the USB vs. AC really has no bearing on the charge current delivered. I'd stay away from charge-only cables just because they'll get mixed in with your standard USB cables and you'll knock yourself out wondering why they don't work. On the other hand, if you really want AC in your battery info order the one I linked.

I keep it in my car... i think I've heard on other threads that USB charging doesn't keep up with GPS (for Directions). Any verify?
Sent from my Galaxy Nexus using XDA App

TheKaz said:
I keep it in my car... i think I've heard on other threads that USB charging doesn't keep up with GPS (for Directions). Any verify?
Sent from my Galaxy Nexus using XDA App
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What's much more important is the rating on the power source. The GN can pull up to 1000mA, if your charger is only rated for 800mA (like many car chargers) it doesn't matter if it's in AC mode.

jdbower said:
What's much more important is the rating on the power source. The GN can pull up to 1000mA, if your charger is only rated for 800mA (like many car chargers) it doesn't matter if it's in AC mode.
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makes sense.. the one I use has dual usb (1.0 and 2.1)

You went and gave me a project for the weekend, and once again science prevails over anecdotal evidence. I took each of my 5 chargers and hooked them up to a 12V power supply that measures current. I then recorded whether the charger reported AC or USB, for the ones with USB I modified a right-angle adapter to short out the data pins, and I measured the current. The contenders:
Verizon Wireless Dual Charger
XTG Dual Port Charger
Griffen Powerjolt Dual USB Charger
Griffen Portjolt Micro
CostMad Dual USB Charger
The VZW model was USB out the external port as I had tested before, however AC out the built-in cable which I hadn't bothered to test. It pulled 0.25A @12V via the USB port and 0.59A via the cable. Hmmm... A hole develops in my previous observation. While I had used this on a long car trip with no issues, it was via the built-in cable.
The XTG was new, I hadn't used it before as it's in the car I rarely drive. It reported USB and 0.22A. With the adapter to make it report AC it pulled 0.48A.
The pattern was set. I had expected the Griffen adapters to be built more appropriately but the dual charger reported 0.22A without the adapter and 0.42A with. I had used this without losing charge in the past so this was surprising to me, but it's possible I just wasn't drawing as much current because the screen was dimmer or something.
The compact Griffen adapter (which is great for a laptop bag, BTW) pulled 0.21A and 0.47A respectively.
The cheap CostMad adapter was the only one that performed well out of the box, both reporting AC and pulled 0.57A.
In theory, a perfect adapter should pull 0.42A. Anything more is waste, anything less means it's not keeping up. I have doubts about the Griffen 2x allowing for a full amp, but the VZW and CostMad chargers are pretty lossy. What's even worse is that I'm pretty sure the VZW charger is rated for 800mA (but I can't find an actual spec on it) which would mean that it pulled the most power for the least current. Not that this really matters unless you've got an electric car.
Sorry for misleading you earlier, I should have checked the other port of the known-good VZW charger and probably doublechecked the numbers on my other "known good" charger. Still hating cables that work for charging but not for data, I ended up modifying each of the chargers to short the middle pins (except for the VZW one). If I didn't have the soldering iron for this, I probably would have gone for some of these instead.

Grant H said:
There has got to be a standard car charger on the market with the middle usb pins already soldiered!
I found this on Amazon which advertises itself as a rapid charging device.
http://www.amazon.com/gp/product/B000S5Q9CA
Click to expand...
Click to collapse
CyberPunk7t9 said:
Make sure the charger has the IC (rapid) chip. I use this one:
http://www.amazon.com/Motorola-Vehicle-Adapter-micro-USB-Charger/dp/B000S5Q9CA
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Click to collapse
I'm using the same one and it works perfect. Charges even when GPS navigation is running.
Make sure you select Amazon as the seller though. I heard there are a lot of fake ones.

Grant H said:
There has got to be a standard car charger on the market with the middle usb pins already soldiered!
I found this on Amazon which advertises itself as a rapid charging device.
http://www.amazon.com/gp/product/B000S5Q9CA
Click to expand...
Click to collapse
+1 to those recommending this one. I have this exact model and it does indeed charge at the "AC" rate, about twice as fast as the "USB" rate.

TheKaz said:
I keep it in my car... i think I've heard on other threads that USB charging doesn't keep up with GPS (for Directions). Any verify?
Sent from my Galaxy Nexus using XDA App
Click to expand...
Click to collapse
The Motorola one will charge even when using GPS. I have a friend I bought one for that uses his GPS all day and loves the Motorola charger.

I'm Having Charging Issues - Are All Micro USB Cables Created Equally?

I bought an OEM Samsung wall charger that charges at 1 Ampere. I started to charge my Zerolemon battery with it yesterday at about 6pm and here it is today and it is only at about 80% charge rate. Something is not right. I contacted the seller and they told me that the charger is from Samsung and it charges at 1 Ampere. It is either the charger is a knock off or my Micro-usb cable that connects into the wall charger is not the right kind.
Are there different variations of micro-usb cables that will work better? Some that allow more current to flow over them than others? My cable says that it is 28awg/2C. I remember when I had a playstation 3 I had problems with syncing the device with my playstation 3 with the USB cables I had bought. After tons of research it was the USB cables that were the issue. They didn't allow enough current to work properly with the PS3. I'm starting to wonder if I'm having the same issue with the Samsung Wall Charger. Is the 28awg wire gauge too thin?

---->[email protected]<---- said:
I bought an OEM Samsung wall charger that charges at 1 Ampere. I started to charge my Zerolemon battery with it yesterday at about 6pm and here it is today and it is only at about 80% charge rate. Something is not right. I contacted the seller and they told me that the charger is from Samsung and it charges at 1 Ampere. It is either the charger is a knock off or my Micro-usb cable that connects into the wall charger is not the right kind.
Are there different variations of micro-usb cables that will work better? Some that allow more current to flow over them than others? My cable says that it is 28awg/2C. I remember when I had a playstation 3 I had problems with syncing the device with my playstation 3 with the USB cables I had bought. After tons of research it was the USB cables that were the issue. They didn't allow enough current to work properly with the PS3. I'm starting to wonder if I'm having the same issue with the Samsung Wall Charger. Is the 28awg wire gauge too thin?
Click to expand...
Click to collapse
- charger is rated 1amp but usually puts out less depending on the quality and efficiency of it. You won't get the fastest charge with a 1amp psu. Get yourself a cheap 2amp and have plenty of headroom.
- also, if voltage in your wall outlet is low (rare) that would affect psu output.
- yes super thin usb cables can be part of the cause.
- of course, if the cable is meant for PC charging, it will be wired in such a way, to not exceed 450ma (or so) whereas a usb cable or charger that is meant and wired for fast charge, will provide...for me...1150ma (Search/Research my past posts for more detailed info)
- also, most kernels, slow down the charge rate as the batter gets closer to 100% charge.
- a bad battery or custom kernel with bad code, could both affect charging speed.

Slow QI charging

Ordered a QI charger off Amazon (the same Lerway Chinese brand one everyone seems to get) and it's charging incredibly slow. Not sure if the app I'm using to record the charge rate is incorrect or I'm not reading it correctly but it says it's charging at only +200mA max sometimes as slow as <50mA.
Anyone else experience this?

skusa93 said:
Ordered a QI charger off Amazon (the same Lerway Chinese brand one everyone seems to get) and it's charging incredibly slow. Not sure if the app I'm using to record the charge rate is incorrect or I'm not reading it correctly but it says it's charging at only +200mA max sometimes as slow as <50mA.
Anyone else experience this?
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Click to collapse
What kind of power source you use to power the charger and what kind of cable do you use?
If you connect the charger to computer USB port it will not provide enough power for the charger. Same with cheap cables, like the ones mostly included with the generic QI chargers. You need a premium USB cable.
Also if you have a thick case on your phone it will diminish the charging current received by a coil in your phone.
Firstly check how much power and what current your charger gets, so instead of plugging the QI charger, plug your phone and check what amperage you get (I use Current Widget). If it's less then 1600mA (maximum amperage that N5 will allow from direct charging through cable) your charger is underpowered and you need to change socket charger to 2A one. If you're using 2A socket charger and still get under 1600mA then your micro USB cable isn't good enough.
Properly and fully powered Qi charger should charge your bare phone (without a case) at about 700-800mA.

Znamir81 said:
What kind of power source you use to power the charger and what kind of cable do you use?
If you connect the charger to computer USB port it will not provide enough power for the charger. Same with cheap cables, like the ones mostly included with the generic QI chargers. You need a premium USB cable.
Also if you have a thick case on your phone it will diminish the charging current received by a coil in your phone.
Firstly check how much power and what current your charger gets, so instead of plugging the QI charger, plug your phone and check what amperage you get (I use Current Widget). If it's less then 1600mA (maximum amperage that N5 will allow from direct charging through cable) your charger is underpowered and you need to change socket charger to 2A one. If you're using 2A socket charger and still get under 1600mA then your micro USB cable isn't good enough.
Properly and fully powered Qi charger should charge your bare phone (without a case) at about 700-800mA.
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Click to collapse
Thanks for the info I thought I was going crazy.
No case so that isn't an issue.
I have the phone connected direct to a 3A charger currently and am only getting 995mA charge rate with the screen on and it looks like full 1.5A with the screen off. Maybe a defective QI charger?

Nope. Everything is normal. You just need a better cable that will manage to transfer 2A of current.
QI charger needs 2A input to give 1A output on a coil. Giving about 70-80% efficiency rate, your phone would be getting about 700-800mA.
Since your charger gets only about 1A input it gives about 500mA output. Therefore giving that efficiency rate, your phone should be getting about 350-400mA tops. It is possible that your charger has lower efficiency rate (some have about 50-60%), so the values that you're getting are pretty normal unless you use a premium micro usb cable, preferably with thicker, like AWG24 or lower (the lower value the better) power wires.

Might want to try these cables, a lot of people have had great luck with using them on Qi chargers. Don't know which length you would need, they have 3 and 6 foot cables. For the price, I'm ordering 6 6ft cables.
http://www.monoprice.com/Product?c_id=103&cp_id=10303&cs_id=1030307&p_id=9762&seq=1&format=2

Why is my 5x "Charging slowly"?

Just got my 5x today, and it does "rapid charging" when I connect with the charger in the box, but when I connect using other USB cables/plugs (one supports QC 2.0, the other is a regular charger but supports 2.1A charging), I get a message that the device is "Charging slowly."
Are there other certain specs that a cable or charger has to have to take advantage of rapid charging?

Fast charging on USB-C is apparently very picky when it comes to cables. I havent't tried charging from the USB-A cables that I bought, but the reviews for one that I was considering said that the cable limited the charging capability to 500mA. I know little about qcomm's Quick Charging but I do know that it requires feedback from an enabled device before it will allow full power. I wouldn't be surprised if the lack of that feedback from the N5X was limiting current from the charger, but it definitely looks like a quality cable is the first step to success. Notice how thick the factory LG cable is...
Most cables limit current by a significant amount. Even factory ones. That's why the OnePlus One charger was so popular. The wall dongle was nothing special (2.0A) but the cable was thick enough to actually let it output that current. The only difference now is that our phone will actually tell us if it's hooked up to a crappy charger/cable.

Thanks for the reply, I'll have to do some hunting on Amazon for another cable and see what happens.
Appreciate it if anyone else can chime in too.

the Nexus 5X does not support Qualcomm Quick Charge, at all.

Thanks, I know QC is not supported, I was just offering up that I tried one, and that I tried multiple charges that support 2.1A charging.

Interestingly enough, if I use either of the QC certified chargers that I got along with my S6 (which only output 2A) I get rapid charging. Using an Anker QC charger (also 2A) I don't, and using a different charger (can't remember the brand at the moment, but also 2A, but not QC), I also get slow charging.
Hmm...