USB Charging with newer devices - General Accessories

Short version: what is the best way to charge a newer device from a USB port that only outputs 0.5a?
Long version:
Been out today in my new car and tried charging my phone from the built in usb... didn't do anything. Makes the charging noise on the phone but no charge.
Obviously I'm guessing it must be only outputting at 0.5a which is very low for today's devices... what can I do? Is there any way to bump up a 0.5a to higher easily (appreciate this might vary by a billion factors, but guess the USB is coming off the car's 12v rails somewhere along the line...)
Another thought that came to me was putting a battery pack that charges slower in the middle, but i don't know if this will work given that i'll probably be drawing more than i'll be getting in to it... and can they even charge as they are outputting?
Any thoughts welcome!!
Cheers
Xperia Z5

Silly question, but have you considered buying a separate phone charger that plugs into the cigarette lighter?
If your device supports Qualcomm QC 1/2/3 there are car chargers that support that protocol. If your device only supports 5V charging, there are chargers that put out up to 2.4 Amps.
I'd recommend purchasing one from a well know brand like Anker (I've only ever purchased 1 charger, it seems to work fine and it was this brand) or several phone manufacturers and cell providers sell their own.
If you absolutely MUST be plugged in over USB (for multimedia?) I don't think there really is a good/safe way to "boost" the output of the port in your car. They provide the USB port so that they can check the box on the features list for "Yes we have a USB port". They're doing this at as low of a cost as possible with little regard for how well it works or if it will charge your device well.

That's what I've ended up going for. It's not ideal as the USB is in the way of the gearstick a bit, but it's all I have. If I come up with a better way then I'll let you know!!

Related

Using 3rd party chargers

Hi, I have just recieved my TP2 and was reading the manual when I noticed that it stated "Only the AC adapter and cable provided with your device must be used to charge the battery". However I have two USB car chargers and two further AC usb ac chargers from previous phones (a MPX200 and a HTC 730) and several mini USB cables (standard not HTC custom ones). Is it safe to use any usb charger or cable, and the manual is just being pedantic or is there a good reason to only use the supplied charger/cable.
Thanks
Tom
I sometimes don't use the usb cable that comes with it. I use my others usb cable to charge it too. well as long as you checked the voltage before you charge. Like the car usb charger, I guess pretty much standard, as long as it is a 12volt :> Even at home I use different usb cable too.
In general it should be fine. Those warnings are always present, just like the comment to always use the maker's batteries. This is simply because
1. They want to make more money and they will if you buy original products from the phone manufacturer.
2. In the case of warranties, if you used a cheap charger with a defect, they are not responsible for the consequences should something go wrong. If you only use their cables and chargers, they can't really say it was your fault for using a knockoff/generic charger.
A friend of mine even uses his Blackberry charger to charge his Touch HD
When in doubt, check the output of the charger you are using: a standard HTC charger churns out 5V, 1A
USB cables are pretty standard so there isn't a big difference - probably except in build quality of the eletrical contacts and the width of the jack - I have one cable that cannot be inserted into my TP2 without a bit more force.
My TP2 Verizon (CDMA) is on the way. I use an "IGO" car charger and have tips for several phones and IPOD Classic. Interesting that most of my mini usb phones use the "a32" tip and the TP2 is listed as using an "A53" tip. May have a circuit for when fully charged. Both are mini USB.
I say an advertisement for an AC wall charger that says charges A"" usb devices. You plug the USB cord into it. Now why would that be safe for an IPOD, TP2, Motorola..... but not DC current????
Maybe they just lie!
The voltage is not an issue, al usb chargers deliver close to 5V but some deliver low current and the HTC phones prefer >500mA but even so less than this will just mean a longer charge time.
HTC recommend you use their cables/chargers as a safety measure because they use a non-standard connector with one flat side for their headset.
Two things can happen using a standard mini usb in this socket if you are not carefull.
a, A standard connector puts extra stress on the socket due to movement and can cause damage. (see prev device threads on Poss mini usb failure)
b, Some device specific usb chargers can have plug cross-connections to denote charger or data cable recognition and can subject data lines to constant 5V (not usualy a problem)
Basically they are issuing a disclaimer for the non-standard mini usb and trying to sell extra acc's at the same time.

In car battery charging

I have travelled to devon on Saturday and used Google maps navigation which is simply superb as u could see the traffic jams in advance (believe me there were plenty of them) I had my phone charger charging my desire but the battery drained still any idea why surely the charger should charge it or keep the power at the same level ?
Sent from my HTC Desire using XDA App
Anyone surely someone must know why the car charger hasn't enough power to charge the phone when running navigation and the normal phone functions
Sent from my HTC Desire using XDA App
I have no solution but I have the same problem. Quite frustrating.
You need a charger that outputs at least 1000mA. Most in-car chargers only output 500mA, and so the phone will discharge quicker than the charger can charge it.
Regards,
Dave
foxmeister said:
You need a charger that outputs at least 1000mA. Most in-car chargers only output 500mA, and so the phone will discharge quicker than the charger can charge it.
Regards,
Dave
Click to expand...
Click to collapse
especially with some GPS apps that consume lots of juice...
Any suggestions which are the best chargers ? Does anyone know what the new HTC dock will incorporate ?
Sent from my HTC Desire using XDA App
Get a cheap USB cable extender, cut it in half and short the middle 2 pins. Don't remember what colours they are. Look on Wikipedia.
I had same problem. Not anymore. Charges properly when I plug in through the custom cable.
This is a common problem.
It bugged me sufficiently that I investigated it in detail.
The Desire, and presumably some (all?) other HTC phones, employ relatively complex charging circuitry.
When you plug a USB cable into the phone, the phone does at least two different checks to determine what type of power source you have just connected.
If you have plugged in a mains powered official HTC charger, which has a rated output of 1A, then the phone knows that it is safe to draw a maximum of 1A from that charger.
The phone will then draw enough current to power itself and, on top of that, charge the battery at the same time.
This current will typically be in the region of 800mA (0.8A) to 900mA (0.9A).
Under these conditions there is enough current to power all the functions of the phone, including WiFi, Bluetooth and GPS, as well as the usual GSM radio and the phone's other functions, as well as being able to charge the battery.
However, if the phone believes that it is connected to a power source with a lower rating such as a standard USB port, then it will limit the maximum current that it draws from that power source to between 400mA (0.4A) and 500mA (0.5A) as this is the maximum officially provided by a USB port.
In other words, the phone is intelligent enough not to overload a standard USB port but, when more power is available, it is able to use it.
The mechanism that HTC uses to detect a power supply capable of supplying 1A, as opposed to a USB port, is very simple indeed.
When the phone detects that an external power source has been connected, it checks to see if the two data lines of the USB connector on the bottom of the phone have been short-circuited.
If they have been short-circuited, the phone takes this to mean that a suitable power source has been connected providing a current of at least 1A.
If the data lines are not short-circuited, the phone assumes that the power is coming from a USB port or other device not capable of providing more than 500mA.
In practice, the way this has been implemented is that within the official mains powered HTC charger, the two data pins of the USB connector are shorted together.
As soon as you connect this charger to the Desire, the phone detects the short-circuit and knows that it is connected to a charger capable of supplying 1A.
This particular trick seems to be something unique to HTC rather than being a universal standard, although this is a bit of a guess on my part based on having looked at only a few other chargers.
What this means is that if you have a car charger that is rated at 1A or higher, your HTC Desire will still only draw a maximum of 500mA from this charger.
This problem is easily rectified by opening up the charger and soldering together the two centre pens of the USB connector so that the phone sees this short-circuit and realises that it can safely draw I higher current from the charger.
Unless you know what you are doing and fully understand what I have explained above, then please don't go fiddling around with your charger.
I have carried out this modification myself on a couple of non-HTC mains-powered chargers and a couple of 12V car chargers with 100% success.
I have, however, found that some 12V chargers, even though they are rated at 1A or even 1.5A do not result in the Desire drawing the expected current.
What I found was that the phone would draw only about 250mA and then, after I had shorted the data terminals within the charger, the phone would draw about 450mA but not the 850mA or so that I had expected.
I have yet to determine with certainty why this is but it appears that as the phone begins to draw current from the charger it is able to detect if there is even a relatively small dip in the voltage coming from the charger and, if so, the phone backs off on the amount of current that it draws.
I will be doing a few more tests in my electronics lab to try and get to the bottom of this and provide a more detailed analysis and, hopefully, a useful solution.
In the meantime though, I have at least solved the problem that I was having and, based on numerous forum posts, the same problem that many other people have been having with car chargers not effectively charging the Desire.
Tim
mercianary said:
Get a cheap USB cable extender, cut it in half and short the middle 2 pins. Don't remember what colours they are. Look on Wikipedia.
I had same problem. Not anymore. Charges properly when I plug in through the custom cable.
Click to expand...
Click to collapse
Snap!
I didn't see your post before making mine (above) but my experimentation agrees fully with what you've said.
You can do it the way you've described, by modifying a cable, or you can do it inside the charger itself.
Just make sure that the cable going to the phone has all four USB wires in it. Some of them only have the two power wires, so the phone will never detect the short circuited data lines.
Tim
If you do not want to open your car charger, you can always create a male to female adapter that shots D+ and D- on the female side like the one in the attached picture
Obviously, the charger needs to be able to provide the 1Amps that are needed. If not, it will at best shutdown in protection mode, at worst fry completely with a great chance of fire...
Interesting stuff...
I bought an official HTC car charger and noticed that the included usb cable, when plugged into a pc, does not allow data transfer, only charging.
Can anyone explain that ? Why would there be a difference in the wiring ?
They want you to buy an official USB cable I guess ? Considering any microusb cable works I'm surprised they bother
Maybe because they just put the two VCC and GND wires in there, thus saving on the cabling cost.
Ok how about this then......
I have a USB port I'm my car (to plug in music on a dongle I presume) if I use the USB lead from my charger supplied with the phone (which also works as a data cable) I get a the charging status icon on the battery bar.
So......
Is my phone charging at 1 amp on the car, and at home or am I getting 0.5 on both or something else?
Sent from my HTC Desire using XDA App
_Crusoe_ said:
Ok how about this then......
I have a USB port I'm my car (to plug in music on a dongle I presume) if I use the USB lead from my charger supplied with the phone (which also works as a data cable) I get a the charging status icon on the battery bar.
So......
Is my phone charging at 1 amp on the car, and at home or am I getting 0.5 on both or something else?
Sent from my HTC Desire using XDA App
Click to expand...
Click to collapse
If you check your battery stats by dialing *#*#4636#*#* and look at battery info, then you can see if it is charged by USB (max 500 mA) or at AC (more then 500mA)
I bought the official HTC charger, works perfectly.
thanks a lot for the explanation. I went for an uprated USB car charger but was still using normal cables to plug into it and the phone wasnt keeping up when bluetooth and GPS was on and was flat by the end of a long journey. Have tried the mod and phone is showing as plugged into AC so hopefully this is going to sort my issues.
So am I right in saying that, unless you get one which has been adapted as described above, there is no real difference between one in-car charger and another - none of them will be up to the job of keeping the phone full of jiuce whilst running GPS over a long journey.
Was thinking of shelling out for a Brodit kit, but at £50+, I'll stick with a cheap one.
Narco77 said:
Interesting stuff...
I bought an official HTC car charger and noticed that the included usb cable, when plugged into a pc, does not allow data transfer, only charging.
Can anyone explain that ? Why would there be a difference in the wiring ?
Click to expand...
Click to collapse
I got the offical charger and the usb cable is fine for data transfer.
Bingo Accent said:
So am I right in saying that, unless you get one which has been adapted as described above, there is no real difference between one in-car charger and another - none of them will be up to the job of keeping the phone full of jiuce whilst running GPS over a long journey.
Click to expand...
Click to collapse
Not really.
For the "mod" to work, your charger must be able to source at least 1000mA which most can't anyway.
So you first have to find a charger that does and then, if it's not already the case, short the D+ and D- cables together.
Note that this can be done by disassembling the charger (not being sure of being able to put it back together), by using conductive glue on the USB plug itself (a bit invasive) or by using an adapter like the one I shown in my previous message (but you need to do it yourself or have someone do it for you)

Are iPad chargers compatible with Galaxy Tab 10.1?

I picked up one of these chargers:
http://www.macally.com/EN/Product/ArticleShow.asp?ArticleID=326
which, in principle, should charge the Tab. It does charge it but it also does some strange things while plugged in:
1. Starts MTP USB mode
2. Completely messes up digitizer - I've installed TouchScreenTune and in the test area I can see when I touch, sometimes the perceived touch seems to rapidly cross the entire vertical area and in regular use it will activate the status bar when I touch anywhere.
I exchanged it for this one:
http://www.macally.com/EN/Product/ipod4show.asp?ArticleID=391
It doesn't have as high a wattage output but still higher than a standard USB charger so should charge faster.
I still get:
1. MTP USB mode
2. not quite as messed up digitizer - seems to be okay in normal use but when I test it in TouchScreenTune I can see that the perceived touch is very jittery. It's now jittery only to a small amount of error so it's usable, but something is going on.
I've also found the tablet completely non-responsive to touch a couple of times today (not plugged in) and eventually it comes back but behaves very slowly until I reboot. I don't know if this has anything to do with the charger or just a coincidence.
I'm concerned with the behaviour of the digitizer that these chargers are doing something bad to my tablet. These behaviours don't occur when I use the official charger. I was hoping to get something with multiple charging ports so I have less to carry and plug in when I travel.
Should I be concerned about use this charger? If so, other than the official Samsung charger, does anyone know of a compatible multi-port charger?
Thanks!
You might be looking at different effects caused by different things.
1) There are two different kinds of USB cables for the Galaxy Tab 10.1: a data cable and a charger cable. These are slightly different. Using a data cable will still allow the Tab to charge, but probably slower. But this can cause the MTP USB mode to kick in (but this also depends on the charger)
2) Some chargers go way above the normal 5 Volt. With most devices that is not a very big problem. But capacitive touch screens are very sensitive to that. That's most probably what you notive. I see the same if I use some cheaper chargers.
3) I don't think your touch screen is damaged by the use of these chargers. If that would be the case, it would probably malfunction all of the time and not occasionally. Chances are a lot higher that you installed some new software or widget that is behaving badly.
USB chargers designed for apple devices in principle will not supply more then 0.5A to non-apple devices.
Apple uses a special technique to signal to the USB charger to supply more power, while non-apple devices uses a different technique. And unfortunately all the charger manufacturers only seem to consider Apple.
So all those chargers proclaiming 2.1A that you can find on Amazon or eBay are all designed for Apple devices. And don't believe when it says on Amazon or eBay that Android devices are supported. Read the reviews and you will typically find someone with charging problems with a non-apple device.
USB chargers are basically all the same except for the amperage that they put out. The stock GTab will not charge very well unless the amperage is around 2A. If you root, you can install a tweak that allows the device to charge with any amperage but with the typical .5A charger it will take a lot longer than with a 2A version.
I use the charging pucks for my iPhone and my wife's iPad interchangeably for those devices and my GTab. They all work fine. The iPad puck puts out about 2A and is about the same as the one that ships with the GTab. Since the GTab version is on my desk, I also use it to charge a bunch of other USB devices such as my hands free car speaker and some wireless headphones. I just plug the appropriate cable into the puck. I have not experienced any problems and suspect that I could use my wife's iPad puck the same way. (I have not yet tried this).
I just ordered a couple dual 2A USB car chargers that allow two USB cables to be plugged in, each getting 2.1A. From what I have been able to discover, these devices will charge just about anything as long as the charging cable has a standard USB connector. They come from China on eBay for less than $3 ea.
I will follow up this post with a review when they arrive.
Bob
USB chargers are not all the same.
"Modern" Adapters that implement the USB Battery Charging Spec, short the middle two data wires (D- and D+), the device can use that to detect that it can draw up to 1.5A (instead of the 0.5A that you get from a regular port).
Apple instead using a different (non-standard) scheme where they communicate to the power supply using voltages, and where different voltages represent different Amperage (I don't know the exact details).
So power supplies sold for Apple devices, as far as I have seen, do not short the data wires and as such a non-Apple device will not draw more then 0.5A
*edit*
Just to add to this, because apple devices communicates with the charger over the two data wires using voltages, while devices that implement the USB Battery Charging Spec require the data lines to be shorted, the two implementations are incompatible.
What you could probably do, is crack open a 2A apple compatible charger and just short the D- and D+ and have a charger that will charge non-apple devices up to 1.5A. And it should also be possible to put a switch on the charger to switch between Standard and Apple charging mode. But if you mess up, don't come and complain to me!
Here is a nice video on how the apple charging works for the iPhone on youtube. But unfortunately this crap forum software won't allow me to post outside links.
Just do a google search for "reverse engineering apple charger"
I made some usb adapters that plug between any usb port and galaxy tab 7.0 plus usb
I made some usb adapters that plug between any usb port and your samsung galaxy tab 7.0 plus usb connector that allows charging from any usb port. I think it's the same for any galaxy tablet/phone. This way you can charge from any pc, or generic wall charger, any car charger, etc. If you're interested in one let me know. I can list them on ebay or some other site.
See pictures, nothing fancy but they work perfect with any charger and or usb port
Pic 1 is adapter
Pic 2 is adapter plugged into portable 12000mAh battery charger made for apple products
Pic 3 I added another adapter I made in between to measure amperage
Pic 4 is screen shot showing "AC" not "USB" and little batter icon without RED "X"

Combo USB wall receptacle, 700mA or 2.1mA?

I was thinking about putting a new receptacle with USB and one outlet somewhere on my kitchen counter. Problem is the two better companies have two very different amperage's. Cooper is .7a and Leviton is 2.1a, both have two USB ports and one outlet. The charger for our E4GT is 1a and I also have a Galaxy Tab 10.1 that would need the higher amp version, but many have said to NOT use a higher amp charger than the one our phones came with, which is 1.
So what do you think? Is it really that bad for our phones/battery to charge it using a higher amp source? I know our charger cube is small but I also need it in various locations at home or at the office so having an outlet like this in my kitchen would be awesome.
I hate how slow USB charges our phones, so I assume .7 would still be kinda slow and not charge my tablet either.
http://www.amazon.com/Cooper-Wiring-Devices-TR7740W-K-Combination/dp/B007NC5GI4
http://www.amazon.com/Leviton-T5630...F8&qid=1350409796&sr=1-1&keywords=leviton+usb
My vote is for the 700. It will be better for your batteries over time.
Interesting thing that I have learned is that the Leviton version only pushes the higher amps on one of the USB ports. There is no where that states how much the one that gets less does though and I have read that if you plug in a device that does not need the extra amps that USB somehow puts out less amps and it charges slower.
I need to do more investigating though.
revamper said:
My vote is for the 700. It will be better for your batteries over time.
Click to expand...
Click to collapse
I agree to an extent.
I feel that it really depends on how long you keep your usb charged devices. Battery degradation may not be an issue if you upgrade often or are the type that never has anything older than the 2nd, sometimes 3rd, newest model device on the market. Also, a lot of the newer devices require higher amps to charge at a reasonable time. This transitions into charging habits. On the 0.7A charger, you may find yourself leaving devices on chargers over night potentially hours longer after fully charging. This is arguably also damaging to the battery.
Either way you go, you may find yourself with a bunch of 6' microUSB cables from devices taking forever to charge or battery degradation. :silly:
Your phone is only going to use as many amps as it can. Say a GS2 charges at 450ma USB and 650ma AC. The phone will recognize if its USB or ac and allow it to charge according to that. Its not going to charge faster on a 1a charger unless you root your phone and hack those parameters. Doing that is what will cause battery life problems, if not cause a complete failure of the battery and/or the device.. The higher you you set the charging amperage, the more likely you are to have problems.
And phones now (especially any model of GS2) have circuitry to prevent overcharging. Leaving your phone charging overnight is not going to cause any problems.
I don't know if USB wall outlets act like USB or a/c (think about a USB cable with a wall adapter) but plugging into the USB outlet and checking in the battery info in the settings menu or a battery app can tell you.
Sent from my SGH-I777
What's next wireless charger outlets?
Get the higher-amperage Leviton.
Your device will only draw the amps it needs. The GS2 will draw < 1amp. But if you have a big tablet, they can pull the full 2.1 amps.
Since you're doing a 'permanent' wall installation, you're somewhat future-proofing yourself.
Good info, thanks all. I did not know that our phone will only pull the amps it needs, so that is good to know. I may get the higher amp version because I have a Galaxy Tab 10.1 that needs higher amperage.

Fast Charging USB Cable for Cars / laptop

Hey all,
The ONE gets too hot... Solved :good:
The ONE charges slowly... Solved :good:
My HTC ONE was charging very VERY slowly since I got it... And it was actually discharging slowly if plugged in and using navigation in the car..
Now, I don't have the original HTC car charger and its a stupid amount to pay for that...
I've used over a dozen of cables and chargers but none of them would charge properly...
Ordered this earlier this week and it got delivered today
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=321159008835&ssPageName=ADME:L:eek:C:GB:3160
Looks decent, and I would highly recommend it for anyone having charging problems with universal USB chargers.
Just tested it, I fired up Waze (which I usually use), Mobile Data, GPS, Skype in background and anything that would run in the background using as much power as it can .... Streaming Music over Bluetooth.. Screen was ON all the time with MAX brightness
My ONE slowly (really slowly) went from 53% to 54% ..:laugh::laugh:
Regarding ROM etc (if it makes any difference) , I'm running Viper One with ElementalX Kernel. 384Mhz Min and 1674 Max. Undervolted to -50mV & Fastcharge ... plus an Air Vent mounted phone holder for cooling features .. The ONE gets too hot
I can finally use the ONE as a proper nav, without having to worry about switching the screen off every now and then...
Sounds good, and in what charger you use?
Yet again, I must explain that cables do not differ if they are similar quality wise. All certified cables should be 24+ AWG btw. Don't be fooled by things like "fast charging." It mostly depends on the charger you're using. (Unless of course, you bought a crappy cable). Also should add that a 4 pin vs a 5 pin cable also creates a difference in charging time.
Kraize said:
Yet again, I must explain that cables do not differ if they are similar quality wise. All certified cables should be 24+ AWG btw. Don't be fooled by things like "fast charging." It mostly depends on the charger you're using. (Unless of course, you bought a crappy cable). Also should add that a 4 pin vs a 5 pin cable also creates a difference in charging time.
Click to expand...
Click to collapse
That cable shorts the data lines to trick the phone into thinking it is connecting to a compatible charger. Any charger that supply 5V and >=1A should be fine with that cable. I would NEVER use the cable on a computer as the phone will try to pull as much as if it was on a wall charger some where around 750mA - 1A.
rancor22 said:
That cable shorts the data lines to trick the phone into thinking it is connecting to a compatible charger. Any charger that supply 5V and >=1A should be fine with that cable. I would NEVER use the cable on a computer as the phone will try to pull as much as if it was on a wall charger some where around 750mA - 1A.
Click to expand...
Click to collapse
Which in turn would probably fry all your usb ports.
Kraize said:
Which in turn would probably fry all your usb ports.
Click to expand...
Click to collapse
Yep, might not fry a powered USB 3.0 port but don't try this.
Many people (inc me) do not know that there are 24 AWG cable, and would use a stupid standard micro usb cable in to charge the phone in vain ...
Mpro747 said:
Sounds good, and in what charger you use?
Click to expand...
Click to collapse
A standard USB port mounted on Cig lighter socket. It does the job right now
Kraize said:
Which in turn would probably fry all your usb ports.
Click to expand...
Click to collapse
Neelesh35 said:
Many people (inc me) do not know that there are 24 AWG cable, and would use a stupid standard micro usb cable in to charge the phone in vain ...
A standard USB port mounted on Cig lighter socket. It does the job right now
Click to expand...
Click to collapse
you guys might wanna look at this sweet babe, you will know exactly how many hours to fully charge ur HTC One :silly:
http://www.thepowerpot.com/solar-power-optimized-practical-meter
hmm interesting, but if the 24awg cable has a potential of frying your usb port, guess what this one will do
Sent from my HTC One using Tapatalk 4
Neelesh35 said:
Many people (inc me) do not know that there are 24 AWG cable, and would use a stupid standard micro usb cable in to charge the phone in vain ...
A standard USB port mounted on Cig lighter socket. It does the job right now
Click to expand...
Click to collapse
The 24AWG wire used in the cable does nothing for helping your phone charge faster, its the fact that the two data lines are shorted in the cable. This tells the device that it is connected to a dedicated charger, even if it is not, and that it can pull however much current it needs.
Why would you buy a cable for this? Get the right charger in the first place and you wouldn't have this issue. Actual proper phone chargers already short the data pins (in fact, I'm surprised you found one that doesn't). Now you have a cable that cannot be used for anything other than charging.
Also, to whoever said this would fry USB ports: no, it wouldn't. Even with shorted data pins, the host machine still won't put any more power out than it is specified to. In fact, this means that using this cable, connected to a computer, would result in it charging SLOWER than if you allowed the phone to negotiate with the computer for faster charging.
Vincent Law said:
Why would you buy a cable for this? Get the right charger in the first place and you wouldn't have this issue. Actual proper phone chargers already short the data pins (in fact, I'm surprised you found one that doesn't). Now you have a cable that cannot be used for anything other than charging.
Also, to whoever said this would fry USB ports: no, it wouldn't. Even with shorted data pins, the host machine still won't put any more power out than it is specified to. In fact, this means that using this cable, connected to a computer, would result in it charging SLOWER than if you allowed the phone to negotiate with the computer for faster charging.
Click to expand...
Click to collapse
Actual computers don't do a good job of limiting current they assume the device will satay within USB spec.
rancor22 said:
Actual computers don't do a good job of limiting current they assume the device will satay within USB spec.
Click to expand...
Click to collapse
That couldn't be further from the truth. Windows even keeps track of the actual loads (it'll tell you when your USB host reports it cannot provide more power). The host decides how much power to provide the device anyway, it's not up to the device. If the device asks for 50 amps, the PC isn't going to try and serve that up. That would be insane and dangerous.
What it WILL do is start with an initial very low current (like 20mA IIRC). The device has its USB client chip powered by this, and uses it to negotiate. The device will then request however much current it needs. However, USB 2.0 spec states that the maximum is 500mA. The device can request more, but it by no means may expect to receive it. The PC may respond and say that it will only serve the maximum. Often it will respond by saying it will provide as much as it is capable (for some laptops and such, this could be as low as 500-600mA). The device must then deal with what it is given (it can use less, but it CANNOT draw more). Note that host devices can actually provide as little as 100mA if available power is limited.
However, many PCs nowadays are designed for charging, and provide over a full amp. They will do so during negotiation. If you use a charge only cable, you're gambling that the PC will go into a high current (AKA "take as much as we can offer") mode. Not all will do so. Some will follow the actual spec, and force the device into a lower power (100mA max, IIRC) current state, leaving you with basically no charging capability.
Vincent Law said:
That couldn't be further from the truth. Windows even keeps track of the actual loads (it'll tell you when your USB host reports it cannot provide more power). The host decides how much power to provide the device anyway, it's not up to the device. If the device asks for 50 amps, the PC isn't going to try and serve that up. That would be insane and dangerous.
What it WILL do is start with an initial very low current (like 20mA IIRC). The device has its USB client chip powered by this, and uses it to negotiate. The device will then request however much current it needs. However, USB 2.0 spec states that the maximum is 500mA. The device can request more, but it by no means may expect to receive it. The PC may respond and say that it will only serve the maximum. Often it will respond by saying it will provide as much as it is capable (for some laptops and such, this could be as low as 500-600mA). The device must then deal with what it is given (it can use less, but it CANNOT draw more). Note that host devices can actually provide as little as 100mA if available power is limited.
However, many PCs nowadays are designed for charging, and provide over a full amp. They will do so during negotiation. If you use a charge only cable, you're gambling that the PC will go into a high current (AKA "take as much as we can offer") mode. Not all will do so. Some will follow the actual spec, and force the device into a lower power (100mA max, IIRC) current state, leaving you with basically no charging capability.
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Windows keeps a record of what devices have requested, not what they are currently drawing. When you use the cable you are bypassing all if this( the software/embedded enumeration and negotiation for power) and then you are just relying on the hardware current limits. In an inexpensive system and possible even expensive ones the hardware probably only as one current limit if it has one at all. Lets say the USB protection IC as a current limit of 1A. A device that is connected with the charging cable is just going to pull current as if its hooked up to a wall adapter for this example let just say the phone draws 900mA. The dangerous part about this is that the computer has no idea this is going on, if the device doesn't enumerate the computer will never know its drawing current unless it trips an overcurrent limit.
rancor22 said:
Windows keeps a record of what devices have requested, not what they are currently drawing. When you use the cable you are bypassing all if this( the software/embedded enumeration and negotiation for power) and then you are just relying on the hardware current limits. In an inexpensive system and possible even expensive ones the hardware probably only as one current limit if it has one at all. Lets say the USB protection IC as a current limit of 1A. A device that is connected with the charging cable is just going to pull current as if its hooked up to a wall adapter for this example let just say the phone draws 900mA. The dangerous part about this is that the computer has no idea this is going on, if the device doesn't enumerate the computer will never know its drawing current unless it trips an overcurrent limit.
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Your entire post runs on the assumption that the USB host, for some reason, would have no way of controlling its power output other than an overcurrent limiter. Not only is this NOT what the USB spec states, but it's also so hilariously dangerous that if it were true, you'd be hearing about it all the time. It'd mean you could create a device that instantly pulls maximum current from the system, frying any system without an adequate overcurrent limiter.
Vincent Law said:
Your entire post runs on the assumption that the USB host, for some reason, would have no way of controlling its power output other than an overcurrent limiter. Not only is this NOT what the USB spec states, but it's also so hilariously dangerous that if it were true, you'd be hearing about it all the time. It'd mean you could create a device that instantly pulls maximum current from the system, frying any system without an adequate overcurrent limiter.
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I am not disagreeing with you that hosts can control and meter power but it does that by assuming the end device will also follow usb spec and is listening to what it is saying. So yes what I am saying is that for a device that does not follow USB spec and does not enumerate the only current control it receives is a hardware current limit. I don't know the whole usb spec well I know battery charging specifications so if this is completely wrong can you point me to the part of the USB specifications where it says the host must limit current draw. In a perfect system the hardware current limit will change as the host specifies how much power the device is allowed to draw, but more likely the protection IC(s) are just there in the case of a short, esd, or a device that is supplying power to the host (reverse current).
Bought a HTC CC-C200 some time ago for my HTC Desire where it did a nice job. Now with the One I encounter the problem that it discharges when being used (navi, scanning, ...).
Is there any newer original car charging cable that I can use? I do not want any 3rd party china cables
bliblablub said:
Bought a HTC CC-C200 some time ago for my HTC Desire where it did a nice job. Now with the One I encounter the problem that it discharges when being used (navi, scanning, ...).
Is there any newer original car charging cable that I can use? I do not want any 3rd party china cables
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I just bought a RocketFish USB car charger and cable From BestBuy. It charges wicked fast, even when using navi and or streaming. I believe is is 10 watts and 2.1 amp output. That adapter will probably fix ya up, I used to have the same problem but not any more
Sent from my gimped not yet unlocked Verizon One

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