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Anybody come across a car charger that is high current like the HTC wall charger?
Most car chargers are classified as "rapid".
Anything designed to charge an iPad (2.1A versus the typical 1A) will give you plenty of juice. I use the Scosche reVIVE II with Pandora, Bluetooth, and GPS Navigation all on and still have enough power to positively charge my battery.
Fair warning, though, this will cause the phone to get real hot (I've had the overheating warning lights flash twice so far), so make sure you have plenty of ventilation around the phone, keep it out of the sun, etc etc.
Any charger that is at least 1 amp. will do. The phone 'pulls' a max of around 0.85 amps. No need for more then 1 amp.
If it has a replaceable cable, it must be the heaviest gauge, shortest cable, that you can use. I have seen long cheap thin cables that drop over a volt, and the Thunderbolt charges really slowly.
The charger or cable have to state that they for rapid charging. To rapid charge, you need to have the USB D- and D+ lines shorted. If that are not shorted, the Thunderbolt limits the charge current to around 0.35 amps. thinking it is connected to a PC. If they are shorted, letting the Thunderbolt know it can be rapid charged, you get up there around 0.85. You can easily modify the charger for high rate if it is good for at least an amp.
And in the end is heat. Heat and lots of it. It will damage the battery. So put it out of the sun and in cool air like near a vent.
Motorola Rapid Charger on Amazon is the best. I bought two.
http://www.amazon.com/Motorola-Vehi...Q9CA/ref=sr_1_1?ie=UTF8&qid=1309959388&sr=8-1
Review off Amazon
Genuine Motorola charger in retail packaging. 4.75-5.25V 950mA output, works w/ most micro-USB phones like Incredible, etc., June 11, 2010
By
David Pearlman "sound fanatic" (Arlington, MA) - See all my reviews
(TOP 500 REVIEWER) (VINE VOICE) (REAL NAME)
Amazon Verified Purchase(What's this?)
There are so many sketchy sellers selling phone chargers out there, that it can be a bit scary. The problem is that if the charger is poorly made, the output of the charger can be out of spec and can, in some cases, fry the phone you connect to it.
For that reason, when it comes to phone chargers, you should stick to name brands. (They are all made in China, but the name brand ones are usually subject to stricter QA).
When I found this charger on Amazon, SOLD BY AMAZON, I jumped on it. It's a MICRO USB car charger, made for Motorola and sold under the Motorola name, in retail packaging. The rated output is 4.75-5.25V and 950mA.
This charger should work fine with most any phone that uses the MICRO USB connector. The key number to pay attention to is the second one, the rated amperage. This is the MAXIMUM amount of current that the phone can request from the charger. A typical USB port on a PC provides as little as 100mA, and few provide more than 500mA. So this charger should charge your phone faster than when it's connected to a PC. A few phones out now can use up to 1000mA. But that just means they CAN use that amount. If 950mA is provided, they'll still charge, just a bit more slowly.
Note that the amperage (second number) merely tells you how much the charger CAN supply, if requested. The phone itself is responsible for asking for the current. That is to say, if this charger can provide 950mA, but your phone can only use 300mA--no problem. Your phone asks for 300mA and the charger provides all of what is requested. If, on the other hand, your phone can use 1000mA, this charger will provide all it can, which is 950mA--a wee bit less than the max asked for. That's also not a problem; it just means your phone will charge a little bit (not much in this case) more slowly. The rated voltage for this charger is presented in a range of 4.75-5.25V. The "ideal" voltage for a USB charger of any type if 5V. And most chargers for home use are rated right at 5V. But car chargers work in a noisier environment and thus you have the range. This is where a cheapo charger can really do damage, as some of them are poorly regulated and can provide voltages that are WAY out of spec. Again, when you can get a name brand charger from a seller you can trust (Amazon) for such a reasonable price, it's very foolish to consider the cheapo no-names.
This is an excellent quality name brand travel micro USB charger at a price that beats the no-name junk from third party sellers. What's not to like?
BE SURE TO ORDER IT FROM AMAZON AND NOT ONE OF THE THIRD PARTY SELLERS, as some of those have been known to make mistakes with respect to what they ship relative to the listing. I can confirm that Amazon is shipping the P513 /89143N charger, as pictured.
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ddgarcia05 said:
Motorola Rapid Charger on Amazon is the best. I bought two.
http://www.amazon.com/Motorola-Vehi...Q9CA/ref=sr_1_1?ie=UTF8&qid=1309959388&sr=8-1
Review off Amazon
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I've been contemplating buying this one, but I'd like to ask you if it charges your battery with navigation+music going? I have a usb charger in my truck, and with both of those going it just manages to keep my battery level where its at, sometimes losing a % or two.
kr0n1c said:
I've been contemplating buying this one, but I'd like to ask you if it charges your battery with navigation+music going? I have a usb charger in my truck, and with both of those going it just manages to keep my battery level where its at, sometimes losing a % or two.
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From what I've read in the past here on XDA and on the reviews for the charger (on amazon) you shouldn't have a problem. The second review for the charger on amazon states that the reviewer was looking for a charger which actually charged his phone will using GPS and that he found it. It's a very well built charger and cheap. It's made my Motorola and sold by Amazon so buy with confidence.
kr0n1c said:
I've been contemplating buying this one, but I'd like to ask you if it charges your battery with navigation+music going? I have a usb charger in my truck, and with both of those going it just manages to keep my battery level where its at, sometimes losing a % or two.
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It does indeed charge. I've had it since my original Droid and was concerned when I updated to the TB but it will charge the TB no matter what you're doing (I've had Nav running while on a phone call with BT and searching the internet and it still showed it was charging). Just be prepared for your phone to get HOT!! Great charger.
worwig said:
Any charger that is at least 1 amp. will do. The phone 'pulls' a max of around 0.85 amps. No need for more then 1 amp.
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Actually, the phone will pull more than 850 mA. You're probably basing that on using a battery monitor, which only shows the flow of current into/out of the battery. I've seen 800 mA into the battery at the same time I have display, GPS and a phone call going, which is definitely more than an additional 50 mA. It wouldn't surprise me if the phone can take advantage of something more than 1A, since I see a battery drain of more than 200 mA with all of that going when not on the charger.
kr0n1c said:
I've been contemplating buying this one, but I'd like to ask you if it charges your battery with navigation+music going? I have a usb charger in my truck, and with both of those going it just manages to keep my battery level where its at, sometimes losing a % or two.
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I have that Motorola charger and am a heavy GPS user. It charges the battery as if it were plugged into the wall. You'll be very satisfied.
mike.s said:
Actually, the phone will pull more than 850 mA. You're probably basing that on using a battery monitor, which only shows the flow of current into/out of the battery. I've seen 800 mA into the battery at the same time I have display, GPS and a phone call going, which is definitely more than an additional 50 mA. It wouldn't surprise me if the phone can take advantage of something more than 1A, since I see a battery drain of more than 200 mA with all of that going when not on the charger.
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No, that was measured at the 5 volt power supply, based upon a lab power supply. I did a lot of experimenting when I developed the charger and phone mount for my motorcycle. And to get the 850ma from the power supply, I used a very short, maybe 8 inch, USB cable, and a charge voltage close to 5.3 volts. With 5 volts at the power supply, it would only pull about 650ma from the power supply. That was due to the voltage drop in the USB cable. With the 5.3 volts at the power supply, I was getting close to an actual 5 volts at the Thunderbolt. I never measured the current at the battery, but I could see it being a bit more then the 850ma in, if there were a switch mode supply in there.
Though I like the Battery Monitor widget as a rough guide, I never tested to see if the battery current and the battery monitor are accurate.
Does anyone know if the included HTC ac adapter and cable will charge faster than using your pc with the included USB cable?
happimeal said:
Does anyone know if the included HTC ac adapter and cable will charge faster than using your pc with the included USB cable?
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Absolutely.
A PC USB port is limited to under 500ma. The Thunderbolt appears to to limit PC USB draw to about 350ma. I haven't measured the actual current in the HTC charger, but it is a high current charger, and charges my Thunderbolt very quickly. Battery Monitor widget shows high battery charge rates. I suspect it is getting near the max rate up near 1 amp.
worwig said:
Absolutely.
A PC USB port is limited to under 500ma. The Thunderbolt appears to to limit PC USB draw to about 350ma. I haven't measured the actual current in the HTC charger, but it is a high current charger, and charges my Thunderbolt very quickly. Battery Monitor widget shows high battery charge rates. I suspect it is getting near the max rate up near 1 amp.
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HTC charger states 5V/1A on the charger itself.
You can use the Palm car charger for $3.75+tax, free shipping. it is 5V/1A, same rating as the HTC wall charger.
Go here for 25% off
http://www.wireless.att.com/cell-ph...otion/accessories.jsp?source=EC0A0011600jtl10
Add product here, must add to cart to see 25% discount.
http://www.wireless.att.com/cell-ph...027&q_sku=sku4720234&q_manufacturer=&q_model=
Also, if so inclined, you can lop the top off of the charger so that you can use any usb cable (ipod, iphone, anything)
dpham00 said:
HTC charger states 5V/1A on the charger itself.
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That doesn't mean much. That is the MAX the charger can output. The amount that the Thunderbolt will pull varies. If it thinks it is plugged into a USB, it will be less then 500ma. even if the charger is capable of 10 amps.
worwig said:
That doesn't mean much. That is the MAX the charger can output. The amount that the Thunderbolt will pull varies. If it thinks it is plugged into a USB, it will be less then 500ma. even if the charger is capable of 10 amps.
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i have used the Palm car charger, checking with bmw, it shows around 850ma, same as on my htc charger.
worwig said:
Any charger that is at least 1 amp. will do. The phone 'pulls' a max of around 0.85 amps. No need for more then 1 amp.
If it has a replaceable cable, it must be the heaviest gauge, shortest cable, that you can use. I have seen long cheap thin cables that drop over a volt, and the Thunderbolt charges really slowly.
The charger or cable have to state that they for rapid charging. To rapid charge, you need to have the USB D- and D+ lines shorted. If that are not shorted, the Thunderbolt limits the charge current to around 0.35 amps. thinking it is connected to a PC. If they are shorted, letting the Thunderbolt know it can be rapid charged, you get up there around 0.85. You can easily modify the charger for high rate if it is good for at least an amp.
And in the end is heat. Heat and lots of it. It will damage the battery. So put it out of the sun and in cool air like near a vent.
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Click to collapse
um, i am aware that any charger that will do 1A will do. that was my question, what car charger will do 1A. Alot of times, they dont have that info listed on pages that are selling them.
and the whole thing about the D- and D+ shorted together, i do not believe. the HTC cable that came with the phone does rapid charging and i use it for data all the time too. if they D- and D+ was shorted, i would not be able to use it for data transfer. not unless the HTC charger shorts them internally inside the charger.
leoingle said:
unless the HTC charger shorts them internally inside the charger.
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Bingo!!
leoingle said:
um, i am aware that any charger that will do 1A will do. that was my question, what car charger will do 1A. Alot of times, they dont have that info listed on pages that are selling them.
and the whole thing about the D- and D+ shorted together, i do not believe. the HTC cable that came with the phone does rapid charging and i use it for data all the time too. if they D- and D+ was shorted, i would not be able to use it for data transfer. not unless the HTC charger shorts them internally inside the charger.
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Yes, it is hard to find the current info online or even on the package sometimes.
Yes, it is shorted in the charger. I have seen it done in the cable and the cable can't be used for data of course. Not sure why anyone would do that, but they do.
I see that the wall charger for the Galaxy Nexus outputs 5V and 1A. Unfortunately, none of the extra chargers I'd like to use as additional chargers have this output. Some of them are 5.1V, and some of them all put out under 1A.
From what I understand, using a charger w/ a higher voltage could potentially damage the phone. I know that this unlikely considering it's only an extra .1V in my case, but I don't want to risk it.
As for the amps, I believe that using lower amps isn't dangerous, but may result in charging taking longer than normal.
Are these two assumptions correct? Also, does anyone know of any cheap chargers that put out 5V/1A? If you put in "phone charger" in Amazon, the second hit is a Samsung OEM charger that puts out 5V/0.7A, but I'd rather get one that is going to be an exact match.
700-800mah are fine and acceptable for charging. But if wanting to play games on a charger and still get some kind of charge, go with a 1000 mah charger. 1000 mah charger is also best to use while using mhl so you can hopefully not lose battery charge while streaming video over hdmi.
Sent from my samsung gt i9250 which is in the wrong country.
Speaking of the charger... anyone found a cheap charger adapter for the Nexus? I don't like the massive brick of a "international adapter" Handtec packaged with the phone >.>
Dmw017 said:
Speaking of the charger... anyone found a cheap charger adapter for the Nexus? I don't like the massive brick of a "international adapter" Handtec packaged with the phone >.>
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http://www.amazon.com/Samsung-Micro-Travel-Charger-M540/dp/B002HJBM04
http://www.amazon.com/Samsung-Travel-Charger-Adapter-MicroUSB/dp/B0049IE70I
Dmw017 said:
Speaking of the charger... anyone found a cheap charger adapter for the Nexus? I don't like the massive brick of a "international adapter" Handtec packaged with the phone >.>
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I'm using a Griffin charger for the iPhone (1 amp)... it's very small and the plug blades fold up, making it very pocketable. Give the included iPhone cable to a friend.
http://www.amazon.com/Griffin-NA231...?s=electronics&ie=UTF8&qid=1322795627&sr=1-33
alee said:
I'm using a Griffin charger for the iPhone (1 amp)... it's very small and the plug blades fold up, making it very pocketable. Give the included iPhone cable to a friend.
http://www.amazon.com/Griffin-NA231...?s=electronics&ie=UTF8&qid=1322795627&sr=1-33
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it's.. 24 bucks ... for a charger..
lol fml
Dmw017 said:
it's.. 24 bucks ... for a charger..
lol fml
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Haha, it's a nice charger.
If you don't get that one, do get a charger that does at least 700mA... or ideally 1A. Some of the cheaper chargers don't put out a lot of power and it will take a long time to charge your phone.
alee said:
Haha, it's a nice charger.
If you don't get that one, do get a charger that does at least 700mA... or ideally 1A. Some of the cheaper chargers don't put out a lot of power and it will take a long time to charge your phone.
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...you say it folds too huh :/ ....
but for that price, i wonder if there are any samsung chargers that are just as good if not better..
that is Apple, after all
hey isnt http://www.amazon.com/Griffin-Techn...al-USB-Charging/dp/B004EYH5WY/ref=pd_sim_e_10 the same product , it says it does 5 volts at 5 watts ... thats the same right?
edit: some people are reporting that the charger only charges at 0.5A instead of the full 1A on [some] android devices. if you have the charger, can you confirm your nexus charges at the full 1A watts
I've been doing fine with just plugging it into my computer like I always do with every other phone.
Sent from my Galaxy Nexus using xda premium
Dmw017 said:
hey isnt http://www.amazon.com/Griffin-Techn...al-USB-Charging/dp/B004EYH5WY/ref=pd_sim_e_10 the same product , it says it does 5 volts at 5 watts ... thats the same right?
edit: some people are reporting that the charger only charges at 0.5A instead of the full 1A on [some] android devices. if you have the charger, can you confirm your nexus charges at the full 1A watts
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Same one.
Good question on whether it's putting out a full 1A. I guess what I do is check the charge times tomorrow with a few different 1A chargers to see if it measures up.
I use this for home:
http://www.amazon.com/Cellet-Charger-Retractable-Cable-myTouch/dp/B004XVM1T0
And this for the car:
http://www.amazon.com/Griffin-Powerjolt-Dual-Universal-Micro/dp/B0042B9U8Q
Both are dual-USB and put out 1amp. Charges my GNEX and iPhone 4 (work) at the same time without issues.
Just feel like to chime in here for another question.
I know typical USB port from a PC outputs 0.5A while the wall charger outputs 1A, so besides charging time, is there any particular advantages to use wall charger over USB from PC?
I've read somewhere else states that despite the longer charging time using a USB port from a PC, it provides more thorough charges hence is better for the battery than using a wall charger, is this true?
Thanks!
assisterah said:
Just feel like to chime in here for another question.
I know typical USB port from a PC outputs 0.5A while the wall charger outputs 1A, so besides charging time, is there any particular advantages to use wall charger over USB from PC?
I've read somewhere else states that despite the longer charging time using a USB port from a PC, it provides more thorough charges hence is better for the battery than using a wall charger, is this true?
Thanks!
Click to expand...
Click to collapse
I've read that the wall charger drops the battery down to 90ish % after it hits 100% and just goes between the two levels until you unplug your charger
While a USB charge is slower and charges your device up to a "fuller" charge
...I may be unfathomably wrong though
---------- Post added at 10:57 PM ---------- Previous post was at 10:56 PM ----------
man that little Apple charger is so damn cute ... lol , ill probably end up buying it once the 1A volt charge is confirmed
edit: just bought it lol, oh well.. it will probably maybe more or less somewhat possibly work like it should at 1A :}
assisterah said:
Just feel like to chime in here for another question.
I know typical USB port from a PC outputs 0.5A while the wall charger outputs 1A, so besides charging time, is there any particular advantages to use wall charger over USB from PC?
I've read somewhere else states that despite the longer charging time using a USB port from a PC, it provides more thorough charges hence is better for the battery than using a wall charger, is this true?
Thanks!
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I'm not an expert on the subject but I was under the impression that cycles (charge + discharge) were a bigger factor on battery life than something like this. The longer a current is running through the battery (charge or discharge) is detrimental to it's life span.
Leaving a laptop plugged in all the time ruins its battery is my source on this one. I would say it's because it has a constant charge running through the battery.
qreffie said:
I've been doing fine with just plugging it into my computer like I always do with every other phone.
Sent from my Galaxy Nexus using xda premium
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That takes a lot longer vs plugging it into the wall
rashad1 said:
That takes a lot longer vs plugging it into the wall
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True dat. Unless it has changed , USB only outputs 500mA.
Sent from my Galaxy Nexus using Tapatalk
[hfm] said:
True dat. Unless it has changed , USB only outputs 500mA.
Sent from my Galaxy Nexus using Tapatalk
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500mA is the max before the PC will disable the port. So your actually get less current.
There are some ports, depending on the motherboard that have a option of outputting more power for charging devices, and also have the port powered when the computer is off. But a normal usb 2.0 port is limited to 500mA max per spec... so a normal usb 2.0 port charging a phone is drawing less then 500mA, or it would get and over current condition and disable the port.
I design electronics and work with USB and batteries often, so let me clear some stuff up in no particular order:
- PC ports are limited to 500mA so will only ever output a max of 500mA
- You can use a wall charger that outputs 1000mA but on most devices the data pins on the micro USB need to be shorted to tell the phone it can try to draw more than 500mA. This is true for HTC devices for example. That means if you get a cheap charger that doesn't short the data pins, when you plug your standard micro-usb cable into it, it will still only charge your phone at 500mA.
- The charging controller is actually in the phone. It decides based on temperature (there's a sensor in the battery), current, voltage across the battery (current charge) and characteristics of the type of battery to figure out how much current to allow into the battery. Although its true that a 500mA charger may have different affects than 1000mA chargers, there usually is very little perceivable difference. Which is (slightly) better really depends on the charging controller and how it decides when to stop charging.
- When the battery is full, the phone continues to 'trickle charge' for a period of time. This isn't a bad thing. Overcharging a Lithium battery can be extremely dangerous, so normal charging occurs at a high speed and then slows down at a safe limit below the 'true' 100%. After that the phone continues to trickle charge to top up the battery. This is the reason you read in phone manuals you should charge the phone for 8 hours or overnight for its first charge.
- When charging at 500mA, the battery does not get as hot. This usually means you get closer to the true 100% before 'trickle charging' starts. With a 1000mA charge the battery heats up a lot more so charging may switch to trickle much sooner. Here's an example with made up figures.
Lets say you charge your battery with a 500mA charger, and it takes 2 hours. When the phone shows 100% it may actually be at 99%, and trickle charging. Leaving it for another 30 mins may take it to its full capacity.
Now, lets say you charge your battery with a 1000mA charger, and it takes 1 hour. When the phone shows 100% it may actually be at 98%, and trickle charging - It stopped sooner because the battery was hotter. Leaving it for another 30 mins may take it to full capacity.
Conclusion.. the 500mA charger took 2.5 hours, while the 1000mA charger took 1.5 hours. However if you unplugged both when the phone showed 100%, the 500mA charged battery may last longer, and so you think the 500mA somehow resulted in a more thorough charge!
At the end of the day, it doesn't matter which you use. the absolute charge cycles is what counts. Charge to 100%, then dont charge till its 0 for best battery care. Constantly plugging into a charger or dock all day on and off is bad. But having said that, your phone is there to be used, so a sensible balance of the two is the best bet.
Thank you so much for the detailed response, kam187. Would you recommend avoiding using a 5.1V charger, considering the phone came with a 5V charger?
Sent from my Galaxy Nexus using Tapatalk
I wouldn't use it. The 0.1v probably won't make any difference, but it may not be regulated. Chargers with these odd values sometimes don't have any regulator inside them. That could damage your phone as the voltage could shoot up and down as the current draw changes.
Just search amazon/ebay for any MicroUSB charger, and pick one from a reputable manufacturer like Motorola, HTC, Samsung etc. Since all phones now use MicroUSB, there's loads of these chargers around from previous phone models etc.
Here's just one I saw on amazon.com:
http://www.amazon.com/Samsung-Trave...E70I/ref=sr_1_3?ie=UTF8&qid=1322808220&sr=8-3
I've tried to find the maximum current that the nexus will draw, without any luck.
some people have said that the galaxy s 2 draws a max of 1A because the phone itself says 1A, but thats wrong, as it says 1A on 3.7v, clearly talking about the input the phone draws from the battery... not the charging circuit... other people say the galaxy s2 limits current to 650mA for heat/safety reasons... I have no reason to believe or disbelieve this.
Getting back to my question, what's the max current that the charging circuit will take, I know the AC/DC adapter that came with my gsm gnexus is 1A/5V, but that may be more than enough, or not as much as the nexus could handle.
I ask because there are many 5v ac/dc converters that output more than 1A, some over 2A... would the nexus charge faster with this much current, and would it be good/bad for the battery?
this could be easily tested if someone has access to an EE LAB, giving the phone 5v, and seeing how much current it takes... would need a DC volt supply capable of >10W (5v/2A).
8steve8 said:
I've tried to find the maximum current that the nexus will draw, without any luck.
some people have said that the galaxy s 2 draws a max of 1A because the phone itself says 1A, but thats wrong, as it says 1A on 3.7v, clearly talking about the input the phone draws from the battery... not the charging circuit... other people say the galaxy s2 limits current to 650mA for heat/safety reasons... I have no reason to believe or disbelieve this.
Getting back to my question, what's the max current that the charging circuit will take, I know the AC/DC adapter that came with my gsm gnexus is 1A/5V, but that may be more than enough, or not as much as the nexus could handle.
I ask because there are many 5v ac/dc converters that output more than 1A, some over 2A... would the nexus charge faster with this much current, and would it be good/bad for the battery?
this could be easily tested if someone has access to an EE LAB, giving the phone 5v, and seeing how much current it takes... would need a DC volt supply capable of >10W (5v/2A).
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I dont know the answer to your question but my nexus eats amperage like it is going out of style. I can charge from almost empty to full in about 90 minutes.
Sent from my Galaxy Nexus using xda premium
@rbiter said:
I dont know the answer to your question but my nexus eats amperage like it is going out of style. I can charge from almost empty to full in about 90 minutes.
Sent from my Galaxy Nexus using xda premium
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Given the battery is 1850 mAh you are drawing a minimum of 1.85Ah/1.5h = 1.233 amps. Since your battery wasn't completely dead, you are drawing slighlty more.
But was the limit the Galaxy Nexus, or the charger? Also, if one were to use navigation or other power hog while in the car, the current draw should be greater without only some of that going to charge the battery.
[email protected] said:
Given the battery is 1850 mAh you are drawing a minimum of 1.85Ah/1.5h = 1.233 amps. Since your battery wasn't completely dead, you are drawing slighlty more.
But was the limit the Galaxy Nexus, or the charger? Also, if one were to use navigation or other power hog while in the car, the current draw should be greater without only some of that going to charge the battery.
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Click to collapse
if he has the GSM galaxy nexus, the battery is 1750 mah, and assuming his device was off or idle during this time, then the current you calculate is not a minimum, it's a maximum... if the battery was half full to start, then 90 minutes were spent charging half of the capacity, so the current was actually half of the amount you calculated.
to answer this question someone needs a nearly empty battery in a galaxy nexus, with the device off (just to be sure we are only measuring charging current, although most likely it is circuit limited, and not battery limited, so it probably wouldn't matter)...
Then they should try charging it with a 5V DC power source with unlimited current, with a way to monitor the current.
most charging circuits for these type of batteries are current limited, then voltage limited, so the battery must be close to empty so we are sure we are monitoring max current... the latter part of the charge is voltage limited and in the end is very small amounts of current.
I am getting a new usb 2.0 hub soon. I didnt know there was a bc 1.1 compliant device standard, aka battery charging 1.1, that allows charging at 1.5amps. But i think this applies to powered hubs, since usb 2.0 technically only allows 500ma, and of course charging from a computer will only allow 500ma. Samsung recent smartphones allow this type of charging, so im sure nexus can utilize it. And yes, sgs2 was limited to 650mah charging for some reason. I never followed up on if devs overcame the limitation. The sgs2 crowd turned me off from the device because of their elitist attitudes.
Crazy world, ay?
@rbiter said:
I am getting a new usb 2.0 hub soon. I didnt know there was a bc 1.1 compliant device standard, aka battery charging 1.1, that allows charging at 1.5amps. But i think this applies to powered hubs, since usb 2.0 technically only allows 500ma, and of course charging from a computer will only allow 500ma. Samsung recent smartphones allow this type of charging, so im sure nexus can utilize it. And yes, sgs2 was limited to 650mah charging for some reason. I never followed up on if devs overcame the limitation. The sgs2 crowd turned me off from the device because of their elitist attitudes.
Crazy world, ay?
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yeah I'm trying to buy the best ac adaptor for my nexus, but finding info is difficult.. the one that came with my nexus is for europe, and is 5v/1A, but it may not be the optimal current. The market seems to have many adapters capable of 0.5A, 750mA, 850mA, 1A, and 2.1A (marketed for ipad)...
will the nexus benefit from a 2.1A ac/adapter even if it doesn't 'need' it?
The Nexus charger is rated at 1 amp. I'm using my Captivate charger at work, which is rated at .7 amps. I'm thinking just because the Nexus charger is rated at 1 amp, that doesn't meant the Nexus is actually drawing that much power. Anyway, the Captivate charger I have seems to work fine.
Any issues here?
8steve8 said:
yeah I'm trying to buy the best ac adaptor for my nexus, but finding info is difficult.. the one that came with my nexus is for europe, and is 5v/1A, but it may not be the optimal current. The market seems to have many adapters capable of 0.5A, 750mA, 850mA, 1A, and 2.1A (marketed for ipad)...
will the nexus benefit from a 2.1A ac/adapter even if it doesn't 'need' it?
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Just get a 1amp charger. It is plenty, on the safe side and fast fast fast for the nexus. With a 1a Motorola charger I have it charges 1% a minute when I am not using phone. I got that powered hub yesterday. Charging the nexus off of it was about 1.5% a minute and I didn't see battery go above 33 degrees Celsius.
Sent from my Galaxy Nexus using xda premium
let me clarify that im not worried about what will "work" im looking for what's the ideal charger...
yes 0.7A will charge it, so will 1A, but the actual max current draw is still what I'm asking.
http://www.reddit.com/r/GalaxyNexus/comments/nvgt4/chargers_3000ma_worth_the_risk/c3cb636
http://www.reddit.com/r/Android/comments/nystt/galaxy_nexus_power_analysis_why_chargers_cant/
I measured the charging current at just less than 0.5A with the phone on and off. I too was thinking that a higher capacity charger would speed charging.
1 amp chargers are more than adequate. I did this check with the battery at 80%.
طوني تبولة said:
http://www.reddit.com/r/GalaxyNexus/comments/nvgt4/chargers_3000ma_worth_the_risk/c3cb636
http://www.reddit.com/r/Android/comments/nystt/galaxy_nexus_power_analysis_why_chargers_cant/
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Thanks for these threads. I was curious, too, if it does any good or harm to my GN if I plug it into the 2.1A plug of my power bank.
not that i care if i break too but if there some way where i can use my 2.1 amp wall charger to fast charge my phone and use 2.1 amps rather than 1 a
Recently bought a camping lantern that runs on a built in 6v 4.5 AH lead acid battery. It also has a USB connector which is for charging cell phones. I initially thought that the USB would be giving off a safe 5v but on testing it turns out that it is 6 volts straight from the battery.
Is this safe to use occasionally while camping? Will that extra 1 volt kill the battery or is there some mechanism inside the phone to regulate that voltage to a safe level?
Good question....hope someone has the answer for you.
Sent from my SCH-I535 using xda app-developers app
executionist said:
Recently bought a camping lantern that runs on a built in 6v 4.5 AH lead acid battery. It also has a USB connector which is for charging cell phones. I initially thought that the USB would be giving off a safe 5v but on testing it turns out that it is 6 volts straight from the battery.
Is this safe to use occasionally while camping? Will that extra 1 volt kill the battery or is there some mechanism inside the phone to regulate that voltage to a safe level?
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Of course there should be.You get more than 6v in a power socket around the house.
Gkikas said:
Of course there should be.You get more than 6v in a power socket around the house.
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No one plugs their phone directly to the wall socket :/ Thats what the charger is for, it only gives 5v to the phone. Just need to know if it can regulate that 6v to a safe level.
*edit. I think no one here would know about the hardware aspects of a phone. Can someone point me to a forum or anywhere where they may know the answer to a question like this?
May I asked how you measured this?
I'd love to check what output my 12v chargers are outputting
TieNN89 said:
May I asked how you measured this?
I'd love to check what output my 12v chargers are outputting
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A multimeter and a stripped usb cable
executionist said:
A multimeter and a stripped usb cable
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ah yeah
My brain has already flicked off for the day LOL
if you use IRC, try the freenode server in the ##electronics channel. they should help you out there. pretty nice ppl in general there.
Sent from my GT-I9300 using xda app-developers app
?
I'm interested as well. Will 6 volts @ 500mAh fry the phone?
Ok, I am an electronic engineer so a few comments.
I have no idea what kind of charging circuit is in our phones, could probably look it up but ..... in my opinion only 10% above 5V is to be considered safe.
Now you are talking about a 6V battery. That battery is not always 6V. A nice example is the 12V battery in your car which is 12.8V when fully charged. Another example are the cells inside our phones which have a nominal Voltage of 3.7V but are charged to 4.2V.
The Voltage they put on those things is the nominal Voltage.
I would check if there is no electronic circuit in that lamp since I would not connect anything directly to a battery at all.
If you go camping I would check this thing coolook pb-2000. Insert 4 x 18650 batts and you can do a couple of recharges. Very good box for the price and you can salvage 18650 from broken laptop batt packs ... but google and youtube a bit before you do that to make sure you do it the right way.
I'm also interested, any news?
You can see the specs of this type of batteries here. The 6V is nominal, as already mentioned above. The maximum noted is 6.9V and TBH, i would be rather reluctant to test is my SGS3 charging circuit likes the idea of being fed with 40% higher voltage than usual.
Are you sure there is nothing in the lantern that would limit the voltage under load? Could be something as simple as 2 diodes in series, in this case measuring the voltage on the open circuit, totally unloaded, with a DMM that barely draws microamps from it, would show the battery voltage. Try drawing some current from it (use a resistor, a USB LED lamp, etc) while measuring. I seriously doubt a self-respecting vendor would setup a USB port on that thing that would potentially output 40% more than specs, really.
PS: if the port is, indeed, fed straight from that battery, i would rather avoid hooking my SGS3 to it. Even though, it would probably survive.
---------- Post added at 07:08 PM ---------- Previous post was at 06:59 PM ----------
lukesan said:
I have no idea what kind of charging circuit is in our phones...
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MAX77686. Good luck finding the datasheet. And good luck trying to guess if there is anything else potentially fed straight from the USB connector. The bottom line is - i wouldn't dare
Solder this to red wire https://en.wikipedia.org/wiki/Zener_diode
OFC you need 5V model
GR0S said:
Solder this to red wire https://en.wikipedia.org/wiki/Zener_diode
OFC you need 5V model
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Not if it doesn't have a resistor in series. And wait. if the battery is at 6.8 Volt and you have a 5.1 Volt zener and it is charging at 1 Amp so you will need a power resistor. You will have a lot of loss of energy because it will go away in heat.
You could use a dc-dc convertor but believe me forget about it and get one of those charging banks where you can put in your own cells.
lukesan said:
Not if it doesn't have a resistor in series. And wait. if the battery is at 6.8 Volt and you have a 5.1 Volt zener and it is charging at 1 Amp so you will need a power resistor. You will have a lot of loss of energy because it will go away in heat.
You could use a dc-dc convertor but believe me forget about it and get one of those charging banks where you can put in your own cells.
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I'm not sure about how practical it would be to be cutting usb cables and wiring zener diodes just to use this lamp....
I think I had a charger that supplied too much voltage (I'm not positive I didn't measure the voltage output or anything), but I can say that the phone did not like it. It would eventually charge somewhat, but the touch screen wouldn't work and would go bezerk if touched lol.
Again I'm not sure how much V it supplied, but I would assume it was more than 6V. It didn't really damage the phones either, I would try it.
Here's your answer, definitively:
6v at the source (the lantern in this case) will probably be 5v or less at the phone because of the resistance in the USB cable itself. The longer the cable is the higher the resistance will be and thus the more voltage you lose to it. Also, the cheaper the cable (the thinner the wires) the more voltage you will lose per foot.
Here's some specs you can plug into THIS VOLTAGE CALCULATOR:
The USB definition specifies up to 5.3v.
Most USB cables will use 30awg wire or maybe 28awg for the better ones.
Depending on which of the sources I've read, some USB cables/chargers use one pair of wires for charging, and some will use two pairs. You can see that using two pairs of conductors drastically improves the voltage transmission but even still, at 28awg over a 6foot cable you're still losing .75v which puts you at 5.25v and well within the USB spec.
So the lantern is fine to use with your phone with your average 6-foot USB cord.
If you're like me and prefer 10-15 foot USB cords in some places you would actually benefit from a 6v or even 7v power supply at the wall. I've found that even on the OEM Samsung wall charger, when I use a 10-foot cable I don't get enough juice to actually charge my S4. With the screen on the battery charge level still drops. The Galaxy Charge Rate app shows something like 500ma charge rate and that's because there's not enough voltage / too much voltage-drop across the long cable. (Radio Shack sells a modular, adjustable voltage wall-wart power supply as well as USB and micro-USB adapters for it. I'm starting to experiment with it and the long cables.)
USB voltage vs charging current
This is an old thread, but I can confirm that my moto G charges at 6v. Apparently the original Motorola charger outputs 5.75v. I hooked up a variable power supply to my phone. The data lines are shorted together to indicate a high current power source is present. The moto G will test load the power supply before settling on a stable charging current. One that does not cause the voltage to sag excessively. When I applied 5v the charging current was approximately 600 mA. At 6v the charging current was approx 1200 mA. The charging current was measured directly on the phone using an app called ampere.
So I conclude that Motorola use this tactic to ensure their phones charge fastest with their chargers. On the up side, its fun watching my phone go from 40% to 100% in 45 minutes
Any recommendations for sloar portable charger for NOTE-2 ?
I bought already one and instead of charging it is draining down the battery! Probably because it uncomon 11pins USB. This happens when I connect to solar panel. When I connect to battery power bank everything works fine, but my main puprose was to use the solar panels.
Arthur
What is the power output of the solar panel your using?
I think its 0.5 W
Sent from my SGH-T889 using xda app-developers app
Someone chime in here if im wrong. But based on output power of .5 watts, and voltage being 5 volts. I see that as having a current output of 100mAh.
Home computers have a usb output of 500mAh and the standard home charger that comes with it is 1000mAh or 1Ah charger.
Based on that, unless my math is wrong, which it could be as i suck at match, LOL, your not putting enough power into your phone. This is why its draining.
5 watts would give you 1000mAh output, which is whats recomended for the unit. I would say anything less then 3 or 3.5 watts would be breaking even.
IAmSixNine said:
Someone chime in here if im wrong. But based on output power of .5 watts, and voltage being 5 volts. I see that as having a current output of 100mAh.
Home computers have a usb output of 500mAh and the standard home charger that comes with it is 1000mAh or 1Ah charger.
Based on that, unless my math is wrong, which it could be as i suck at match, LOL, your not putting enough power into your phone. This is why its draining.
5 watts would give you 1000mAh output, which is whats recomended for the unit. I would say anything less then 3 or 3.5 watts would be breaking even.
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correct. Minimum you'll need to charge is 5W or 1 amp. 500 mA will just slow discharge. The charger that came with the phone is 2 A or 10W, this is why it charges faster. He'll probally need to charge the battery pack on the solar charger, then use the battery pack to charge your phone.
Sent from my SGH-T889 using Tapatalk 2
Thanks for pointing that out _Dennis_ I have been using a 1 amp charger for mine, charging at night while im asleep. I was not aware that it came with a stock 2 amp charger. Ive got other 1 amp chargers set up from previous phones so i never used the stock one.
So my math above is off by 50% since i was basing it off 1 amp charging, and the stock is 2 amp.
Ok, so if I go towards phone/notebook solar charger, what would be recommended ? My Samsunf tablet comes with 19v 2A adapter so itlooks like if I have charger to supply this same amount of power it should work for Slate and Note2 as well. Right ?
Sent from my SGH-T889 using xda app-developers app
Is 19V the output? If so then NO. The Note 2 requires 5V 2A..