On the Oneplus forum there is a thread where they analysed the dash-charging cable ( https://forums.oneplus.net/threads/...-cable-doing-internally-lets-probe-it.456017/ ).
The topic was finished by somebody posting a teardown of the cable revealing that it's dash-charging capabilities are encoded on a BQ2022 from ti.
The next logical step is to dig into the communication between the phone and the charger.
The same guy that tore down the cable also took a look at the chargers (google translate will be helpfull):
http://www.chongdiantou.com/wp/archives/1228.html Mains
http://www.chongdiantou.com/wp/archives/1339.html Car
Maybe we can continue the investigation here....
So, I did some digging around the Car-Unit with my Logic Analyzer.
Description of setup here: http://imgur.com/a/G7pPN
The charger waits for a current draw (i didn't bother testing it's thresholds) and then reads/checks-for the E²PROM embedded in the plug of the cable (presumably containing an authentication for dash).
At a similar time the phone sends a kind of "preamble" consisting of high-low transitions of varying lengths (but this doesn't seem to important to the charger, it tries to "dash" even without it).
Afterwards the phone and charger start exchanging 9 bits of data in bursts. One USB-Data-Line is clock, the other one is data. The chargers supplies the clock and the first 9 bits and after a short pause the phone gets to reply with another 9 bits as the charger supplies another "clock-burst".
At the beginning (before dash-charging is in effect), the charger sends 150h and the phone replys with 158h.
Once the phone is ready to begin dash-charging it replys with 178h instead.
The charger then configures it's Step-Down Converter for ~4.5V of output voltage and then sends 148h to the phone.
It either replies with 170h if the voltage is too high or 178h if the voltage is correct (I didn't see a reply for "too low", but it might exist).
If the phone replies 170h the charger lowers the voltage by about 100mV-200mV and "asks" again.
Once the phone replies with 178h the charger stops lowering the voltage and sends 14Ch to which the phone replies with 141h.
During the dash-charging process the charger periodically sends 144h to which the phone replies with a number which seems to roughly coincide with the state of charge (i have seen values from 16Eh to 178h).
The charger seems to nudge-up the voltage every once in a while (presumably when the current dropped below a threshold).
If the battery is relatively full (i tested at 90% charge) the "dash-charging-cycle" doesn't even start and the communication stays at an exchange of 150h/158h data "words".
I did some minor probing on the wall-wart with a stripped USB 3.0 extension and found that it uses the same commands but with the lowest bit set (i.e. it adds 1 to the command codes). Unfortunately the USB 3.0 cable had some internal resistance ruining most of the analog measurements.
todo:
- I didn't manage to capture is the transition from dash charging back to "normal" 5V mode at the end of the charge cycle.
- The values communicated at the transition from the voltage-setting process to the dash charging operation are unclear to me (but they appear to be always the same).
Do you think it's safe to use OnePlus 3 brick or car Dash charger with let's say micro USB cable and charge other phones? Or OnePlus power bank?
nitramcek said:
Do you think it's safe to use OnePlus 3 brick or car Dash charger with let's say micro USB cable and charge other phones? Or OnePlus power bank?
Click to expand...
Click to collapse
it's safe as with other phone or cable it will act as a normal charger blocking at 1.5A.
Dash charge will only activate if, the dash cable is used with a dash charging phone or oppo vooc phone.
Le_Zouave said:
it's safe as with other phone or cable it will act as a normal charger blocking at 1.5A.
Dash charge will only activate if, the dash cable is used with a dash charging phone or oppo vooc phone.
Click to expand...
Click to collapse
Great, so It's safe to use my car Dash charger for charging other phones to.
atheist93 said:
So, I did some digging around the Car-Unit with my Logic Analyzer.
Description of setup here: http://imgur.com/a/G7pPN
The charger waits for a current draw (i didn't bother testing it's thresholds) and then reads/checks-for the E²PROM embedded in the plug of the cable (presumably containing an authentication for dash).
At a similar time the phone sends a kind of "preamble" consisting of high-low transitions of varying lengths (but this doesn't seem to important to the charger, it tries to "dash" even without it).
Afterwards the phone and charger start exchanging 9 bits of data in bursts. One USB-Data-Line is clock, the other one is data. The chargers supplies the clock and the first 9 bits and after a short pause the phone gets to reply with another 9 bits as the charger supplies another "clock-burst".
At the beginning (before dash-charging is in effect), the charger sends 150h and the phone replys with 158h.
Once the phone is ready to begin dash-charging it replys with 178h instead.
The charger then configures it's Step-Down Converter for ~4.5V of output voltage and then sends 148h to the phone.
It either replies with 170h if the voltage is too high or 178h if the voltage is correct (I didn't see a reply for "too low", but it might exist).
If the phone replies 170h the charger lowers the voltage by about 100mV-200mV and "asks" again.
Once the phone replies with 178h the charger stops lowering the voltage and sends 14Ch to which the phone replies with 141h.
During the dash-charging process the charger periodically sends 144h to which the phone replies with a number which seems to roughly coincide with the state of charge (i have seen values from 16Eh to 178h).
The charger seems to nudge-up the voltage every once in a while (presumably when the current dropped below a threshold).
If the battery is relatively full (i tested at 90% charge) the "dash-charging-cycle" doesn't even start and the communication stays at an exchange of 150h/158h data "words".
I did some minor probing on the wall-wart with a stripped USB 3.0 extension and found that it uses the same commands but with the lowest bit set (i.e. it adds 1 to the command codes). Unfortunately the USB 3.0 cable had some internal resistance ruining most of the analog measurements.
todo:
- I didn't manage to capture is the transition from dash charging back to "normal" 5V mode at the end of the charge cycle.
- The values communicated at the transition from the voltage-setting process to the dash charging operation are unclear to me (but they appear to be always the same).
Click to expand...
Click to collapse
Really interesting analysis. What's your goal? Enabling dash charging without dash accessories?
(USB-C for example)
My primary motivation is curiosity.
If the protocol turns out to be sufficiently simple to replicate (which is looking good at the moment) I might try and build a dash powerbank to quickly top of my battery. I wouldn't want 3+ Amps going through a flimsy micro-to-c adapter from a vooc bank...
atheist93 said:
My primary motivation is curiosity.
If the protocol turns out to be sufficiently simple to replicate (which is looking good at the moment) I might try and build a dash powerbank to quickly top of my battery. I wouldn't want 3+ Amps going through a flimsy micro-to-c adapter from a vooc bank...
Click to expand...
Click to collapse
hmm, so you're trying to replicate it on the hardware side, that's a cool application and it'd be great to have other options for power banks and car chargers.
i honestly don't know much about the topic, but do you think i'd be possible to replicate it on the software side? ie, mimic the protocol to enable faster charging when plugged into a USB-C fast charging output? (but also limit it to 3A since that's a safe max similar to the Nexus 5X/6P)
I am pretty sure that it is not possible to do it in software only.
The whole point of Dash is to let the charger do the regulating and make the phone just "pass-through" the raw connection to the battery.
You might be able to trick the phone into switching it's "pass-through" feature on without getting the right initialization, but this would frankly be stupid as the result would be 5V from the USB-Port pushing directly into the lithium cell which is supposed to stay below 4,2V. Initially the internal resistance of the USB-Cable might limit the current sufficiently to prevent an immediate catastrophic failure, but I can't imagine it working out well in the long run...
The only possible solution i see for this to work is to have a device that plugs into your existing USB and steps down the voltage appropriately, but that is hardware again.
atheist93 said:
I am pretty sure that it is not possible to do it in software only.
The whole point of Dash is to let the charger do the regulating and make the phone just "pass-through" the raw connection to the battery.
You might be able to trick the phone into switching it's "pass-through" feature on without getting the right initialization, but this would frankly be stupid as the result would be 5V from the USB-Port pushing directly into the lithium cell which is supposed to stay below 4,2V. Initially the internal resistance of the USB-Cable might limit the current sufficiently to prevent an immediate catastrophic failure, but I can't imagine it working out well in the long run...
The only possible solution i see for this to work is to have a device that plugs into your existing USB and steps down the voltage appropriately, but that is hardware again.
Click to expand...
Click to collapse
a physical device which enables dash charging, particularly up to 3A via USB-C and 2.4A via USB-A to USB-C, would be of great use too
atheist93 said:
My primary motivation is curiosity.
If the protocol turns out to be sufficiently simple to replicate (which is looking good at the moment) I might try and build a dash powerbank to quickly top of my battery. I wouldn't want 3+ Amps going through a flimsy micro-to-c adapter from a vooc bank...
Click to expand...
Click to collapse
I bought the Dash car charger to be used as a car charger as well as backup power for camping etc. The dash charger seems to work with a wide range of input voltage. I would guess 8V-28V works fine.
I tested the dash car charger with eight AA Eneloop batteries but it didn't work well. The input voltage dropped from 11V to 6,6V. I think the stress was too much for eight batteries and dash charging didn't work. Ampere (app) displayed a reading of 1120mA for charging current.
Ten AA Eneloops were enough to dash charge the phone twice from 40% -> 90%. I also tested the dash car charger with a 19V PSU and it workerd fine as well.
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
The next step is to buy lifepo 4 / lipo battery and build a case.
Thanks for the work done.
The problems with the enelope is the wiring... I guess there will be a massive voltage drop over the holder/wires and clips.
These things are not made for higher currents. I have seen experiments failing because of battery holders and crocodile clips very often. The problem is that these cables often have massive resistance which is no problem as long there is no current flowing... Greetings from Ohms law
Squabl said:
I bought the Dash car charger to be used as a car charger as well as backup power for camping etc. The dash charger seems to work with a wide range of input voltage. I would guess 8V-28V works fine.
I tested the dash car charger with eight AA Eneloop batteries but it didn't work well. The input voltage dropped from 11V to 6,6V. I think the stress was too much for eight batteries and dash charging didn't work. Ampere (app) displayed a reading of 1120mA for charging current.
Ten AA Eneloops were enough to dash charge the phone twice from 40% -> 90%. I also tested the dash car charger with a 19V PSU and it workerd fine as well.
The next step is to buy lifepo 4 / lipo battery and build a case.
Click to expand...
Click to collapse
How did your project go? And why Lipo batteries? Why not 18650 batts?
MonoTovarisj said:
How did your project go? And why Lipo batteries? Why not 18650 batts?
Click to expand...
Click to collapse
You can get custom Li-Po batteries to fit any size and are generally square. 18650s are cylindrical and there would be wasted space between the batteries so with a Li-Po you would be able to get higher capacity. Just a wild guess
MonoTovarisj said:
How did your project go? And why Lipo batteries? Why not 18650 batts?
Click to expand...
Click to collapse
I ended up using battery from my 18V cordless drill. The battery is quite small and light weight for it capacity. It was the easiest and cheapest option as I need battery backup very seldom.
I did a case for 4 x 18650 and the car charger, but got a little stuck in the project. Mostly because I don't have any electronic skills.
This looks cool.
What questions do you have? I can help out with the electronics. But it seems to be quite straight forward. But to be safe use protected 18650 cells. I can recommend the Panasonic NCR18650b, they are the best ones currently available. See: https://www.gearbest.com/batteries/pp_187046.html. You might need to adjust your design the protection makes them a bit longer than standart 18650 cells.
The design is already for the panasonic protected 18650 cells. However I would have liked a pcb in the buttom with full charging circuit and a usb-c for charging. With my current design I have to take the cells out for charging. :-/
MonoTovarisj said:
The design is already for the panasonic protected 18650 cells. However I would have liked a pcb in the buttom with full charging circuit and a usb-c for charging. With my current design I have to take the cells out for charging. :-/
Click to expand...
Click to collapse
You want to connect the 4 cells in series right?
I haven't found any good 4s charging modules yet.
Building you own charger circuit based on an charger IC is hardcore electronics. I have tried and i took months.
So charging the externally should be fine really.
affmalg said:
You want to connect the 4 cells in series right?
I haven't found any good 4s charging modules yet.
Building your own charger circuit based on a charger IC is hardcore electronics. I have tried and I took months.
So charging the externally should be fine really.
Click to expand...
Click to collapse
Yeah series, as I need the voltage for the car charger, and 3.7 times 4 gives a nice 14,8V for the charger.
Regarding charging that was my conclusion as well, however if I wanted to commercialise it, I would need a built-in charging circuit.
I would be able to get wires to the top poles as well if that would help the design, then you would be able to charge them individually and switch to a serial connection when in use.
Related
hi, all. there is a rumor going around that the tilt will have problems if we frequently use non-original charger or usb cable (the one came with tilt) to charge the phone or transfer data such as causing the tilt not functioning or possibly burn out the device/battery, is that true??? do we always use the original usb cable and charger for charging the ATT tilt or transfering data? cuz I m currently using a usb car adapter to charge the tilt. I m really scare of it if this rumor is true. I don't want my tilt get burnt out. Please confirm or disconfirm it.. many thx
usb from the computer is always 5 volts and .5mAmp
http://en.wikipedia.org/wiki/Universal_Serial_Bus
thats the power pda's use to charge with
unless the computer in question is really defect and provide a non std power
or you charge with a ac charger which provide a different power
you should be safe
Rudegar said:
usb from the computer is always 5 volts and .5mAmp
http://en.wikipedia.org/wiki/Universal_Serial_Bus
thats the power pda's use to charge with
unless the computer in question is really defect and provide a non std power
or you charge with a ac charger which provide a different power
you should be safe
Click to expand...
Click to collapse
thanks for the confirmation. seriously, I didn't believe that a usb cable will cause such serious problems since there is only minor difference in the original cable and a regular usb cable. they all look the same internally except for the terminal shape.
as an extra safety precaution, i wouldn't start the car with the tilt plugged in. might be nothing, might be something. once the car is running then i'd plug the tilt in....
i dont know tho, it could be viable. i remember the dude @ att saying that the tilt uses a proprietary mini usb connection w/ a different set of pins, it could be that the different pins apply or distribute power/data to different places & thus could render a device in operable? just my 2 cents.
Don't plug the phone in while the moon is out and the planets are aligned, it could cause the charger to spike and then brike your phone. j/k
My buddy had a problem with his USB. I think he put in a funky cable and it bent the connectors that are in the mini usb hole. Careful careful.
I would have to agree with that any usb be fine but be careful. When I first got my tilt awhile back I got this free usb car charger with it. It worked fine but something broke on the inside of it cause i could hear rattling inside. Prob a chip or something to tell the charger to stop charging if batttery is full. Well long story short I fried my usb connection and could not charge my phone or sync it. End up exchanging my Tilt out for a new one.
I am using the same USB cable to charge and sync since my Cingular 8125. I never charge using AC power.
As for car chargers, here is a simple way to check for potential power surges during starting:
1) Turn your key to "ON" but don't actually crank it. Let the radio come on and start playing. Now start the engine. Did your radio cut off during ignition?
-If Yes, unplug devices before starting because your car is not wired to supply continuous power to its outlets.
2) With your car off, and the key removed, plug in your phone. Does it start charging?
-If No, wait until the engine is running before plugging in your phone.
I am able to keep my phone connected at all times because as part of my ~$2000 audio upgrade, I also added an industrial-grade circuit breaker (not a fuse, an actual circuit breaker) between my battery and the inside of the car. In 4 years of running it, I have yet to stress it enough to pop.
Oh nice, I haven't seen too many breakers in a car. Saves on those uber expensive fuses.
The Tmobile guys at my store strongly discourage using any other brand chargers on HTC phones. It's not the connector they claim is the issue but the amperage. When I first got my tytn2, my wife's motorola usb wall-wart would work, as well as my RIM wall-wart. Now neither of them do. Only the HTC chargers will work on the phone. Someone theorized that the other company chargers might bend a pin or something in the phone rendering them useless.
The amperage idea doesn't fly with me, as the moto and RIM are less amperage than the HTC. I'd be more worried about supplying too much current than not enough.
I bought a sweet 3 in 1 charger kit from frys for 20 dolla..
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
Be jealous it's ok!
http://www.wirelessemporium.com/pro...-1-mobile-phone-charger-motorola-razr2-v9.asp
Scott_F said:
The Tmobile guys at my store strongly discourage using any other brand chargers on HTC phones. It's not the connector they claim is the issue but the amperage. When I first got my tytn2, my wife's motorola usb wall-wart would work, as well as my RIM wall-wart. Now neither of them do. Only the HTC chargers will work on the phone. Someone theorized that the other company chargers might bend a pin or something in the phone rendering them useless.
The amperage idea doesn't fly with me, as the moto and RIM are less amperage than the HTC. I'd be more worried about supplying too much current than not enough.
Click to expand...
Click to collapse
OK, Of course store guys are going to say that. That's what HTC says. And Store Guys are nothing but Puppets who read papers given to them by corporate and they recite them. Plus they can charge you more, there for make more money, if they sell you a OEM Charger then a "compatible" charger.
stanGib said:
i dont know tho, it could be viable. i remember the dude @ att saying that the tilt uses a proprietary mini usb connection w/ a different set of pins, it could be that the different pins apply or distribute power/data to different places & thus could render a device in operable? just my 2 cents.
Click to expand...
Click to collapse
http://en.wikipedia.org/wiki/HTC_ExtUSB
Plus the cable I got with my Tilt works just like a Standard USB cable so I don't think there is an issue. But what I'd like to see is the Numbers. Using the "HTC USB Sync cable" and a standard USB cable what amps are being sent. And What does the Device Prefer?
It can't use the name mini usb if it's not mini usb. I have a zippy belkin mini usb and it works greeeeat.
stanGib said:
i dont know tho, it could be viable. i remember the dude @ att saying that the tilt uses a proprietary mini usb connection w/ a different set of pins, it could be that the different pins apply or distribute power/data to different places & thus could render a device in operable? just my 2 cents.
Click to expand...
Click to collapse
Just make sure that your car charger has a fuse. If needed, change the fuse to a lower type (one that is just above the recommended for the Tilt, .5a is what I think it draws at). This will protect it from spikes when you start the car.
Scott_F said:
The Tmobile guys at my store strongly discourage using any other brand chargers on HTC phones. It's not the connector they claim is the issue but the amperage. When I first got my tytn2, my wife's motorola usb wall-wart would work, as well as my RIM wall-wart. Now neither of them do. Only the HTC chargers will work on the phone. Someone theorized that the other company chargers might bend a pin or something in the phone rendering them useless.
The amperage idea doesn't fly with me, as the moto and RIM are less amperage than the HTC. I'd be more worried about supplying too much current than not enough.
Click to expand...
Click to collapse
I've used so many different types of USB cables and/or chargers on my Tilt. I have not once had an issue. Just make sure the power ratings are correct and you're good.
Whilst I normally subscribe to the view that the HTC branded part is no better than a decent quality 3rd party part, I have had issues with non-HTC chargers.
I manage the BlackBerries at work, and have tried numerous BB miniUSB chargers (The one with the cord hard wired and the one which is effectively a mains plug to female USB) and neither work with my Kaiser.
I also had issues with car cigarette lighter to USB adapters. As soon as I obtained an official HTC car charger, all the problems went away.
Scott_F said:
...
I'd be more worried about supplying too much current than not enough.
Click to expand...
Click to collapse
You can't supply more current then the device can consume. The number on the charger just shows the highest value of a current the charger can produce without dropping the voltage.
I bought a Cell phone & USB charging kit from BestBuy today and my Tilt got fried when I connected it to this charger after the car had already started. I just noticed the charger output is 5.3V 0.5A whereas the battery pack is only 3.7V ???
hey improtant question. i think that the usb port in the kaiser actually dose get messed up using other chargers. i belive this becouse i used to be able to charge with any charger like some of you but now only htc's charger works. and that sucks but whatever the bad part is the headphones downt work any more. cany any one else that has to use htc's charger confirm that the headphones no longer work?
I've seen issues with various chargers (including one for the Dopod 838pro, Motorolla, and no-name car chargers), where I've seen it not activate the charging mode on the PDA intermittently. Unfortunately, I wasn't able to conclusively rule out that the HTC original chargers will work 100% of the time either, since that particular Tilt unit wasn't mine.
Also for some reason, I've had this accessory fail to connect to the headphones port after using it for a while (with a car charger connected). Fortunately, i had bought a few (for myself and others), and the port on the HTC is still working. So maybe you can try another headphone accessory and see if it's really the port on the HTC that is dead.
From my personal experience, testing, and reading on these forums, it appears that there are three conditions that need to be satisfied for reliable use of the USB port:
First - The Mechanical Fit
Standard mini-USB connecters DO NOT fit the same as the HTC extended USB implementation. To address this, I use the HTC signal splitter (headphone+charger/sync) on almost all standard USB cables for chargeing. It's fully compliant with the HTC in all ways and has added benefits. (see below)
Second - Pinout
The charging circuit in the Tilt (and others) can be finicky with regard to whether or not it works using a standard USB cable. The HTC splitter solves that and allows slow charging from virtually any USB compliant source. I also have the adapter from http://www.pocketpctechs.com/ in my car that even allows you to select the fast charge or slow charge pinout via a switch. (VERY COOL) This works great because I'm usually looking for the fast charge in the car. (Note... fast charge is disabled when transferring data via USB)
Third - Electrical Spec
Voltage is 5V for all USB outputs. Spikes generated in a car are pretty tough to transmit past the step down circuit/ic in the auto USB power adapters. I have never heard of a device being damaged by a spike from the car via one of these adapters. The chip itself would fail to open before frying the USB power client (aka the Phone).
Current draw for these phones is 0.5A for slow charging and around 1A+ for fast charging. This is determined by the pinout of the cable you are using. Slow charge is the default on all data type cables. Some cables sold as "charging cables" enable the fast charge. (The PPC Techs cable has the switch to do this) I recommend using at least 750mA chargers to allow the phone to have enough current to run the gps, bluetooth, etc with the screen brightness turned up and still have a small excess trickle to charge the battery.
I hope this summary helps a bit.
Cheers!
What exactly is the scoop on this? Is it that they overpower the charging circuit (everyone says they charge the phones faster)? Is there a way to tell you're about to do damage?
I don't use the car charger that came with my Kaiser, I have several generic chargers which all work just fine. However I noticed that when running GPS, although the charge light was on, the battery wouldn't really charge. It wouldn't discharge either, I put it up to the extra drain on the phone's power system.
The other day though, my phone... stopped charging? I was driving (GPS) and the phone suddenly beeped a critical battery warning, the charge light was off... but the power was plugged in and the charger's power light in the cigarette socket was on. It WAS making a connection to the phone: if I unplugged it the screen would go dimmer, if I plugged it back in it would get brighter. But it still seemed to be running off the battery, which was draining regardless. The moment I got to my destination, it all powered off. Is this a forewarning of darker circumstances to come?
from what I've read you should not be using generic chargers. The amperage could differ. Therefore, if the electricity in your vehicle spikes you could be riding with a paper weight.
In addition, it is common that your device will not charge (nor discharge) while running your gps application. I play monopoly often while my phone is in the charger and my device usually doesn't charge while I am playing.
Also, I think the pinout on generic USB chargers are different. The ones that are for Moto Razr / Blackberry phones dont work to charge the phones ( as I have a work blackberry and tried it) It didnt hurt my phone, however it just didnt charge. I have heard of others damaging but if its not made for the kaiser, I wouldn't try it.
I've never had access to Moto Razr / Blackberry chargers. While I can't speak for those, I know generic USB chargers would have exactly the same pinout as the stock Kaiser charger. The amperage supplied may indeed differ, I think that might have explained my issue above. It was almost like the charge circuit 'gave up' since the phone was demanding as much/more power as it was getting.
CrArc said:
I've never had access to Moto Razr / Blackberry chargers. While I can't speak for those, I know generic USB chargers would have exactly the same pinout as the stock Kaiser charger. The amperage supplied may indeed differ, I think that might have explained my issue above. It was almost like the charge circuit 'gave up' since the phone was demanding as much/more power as it was getting.
Click to expand...
Click to collapse
My razr charger works perfect with my tilt.. (MOTOROLLA branded - not generic)
Ditto on the motorola razr charger;Have an old razr charger I use it for travelling instead of unplugging my original;works fine!!
+2 on the Motorola branded car charger...charges my Tilt just fine. Now I'm paranoid, though...
CrArc said:
What exactly is the scoop on this? Is it that they overpower the charging circuit (everyone says they charge the phones faster)? Is there a way to tell you're about to do damage?
I don't use the car charger that came with my Kaiser, I have several generic chargers which all work just fine. However I noticed that when running GPS, although the charge light was on, the battery wouldn't really charge. It wouldn't discharge either, I put it up to the extra drain on the phone's power system.
The other day though, my phone... stopped charging? I was driving (GPS) and the phone suddenly beeped a critical battery warning, the charge light was off... but the power was plugged in and the charger's power light in the cigarette socket was on. It WAS making a connection to the phone: if I unplugged it the screen would go dimmer, if I plugged it back in it would get brighter. But it still seemed to be running off the battery, which was draining regardless. The moment I got to my destination, it all powered off. Is this a forewarning of darker circumstances to come?
Click to expand...
Click to collapse
That is the exact same thing I am experiencing with my Tilt.
Tilt is charging from a generic car-to-USB and USB cable.
I start TomTom.
Charging works fine for a while.
Then suddenly the charging stops and the battery is drained.
I found only two ways to get it to charge again:
1. Turn off device with TomTom charging; hold Tilt against cool air flowing from AC; plug into charger (while still off) ... then the phone turns on and charges.
2. Take out the battery; put it back in ... start phone.
It does seem that either the phone can draw power faster than a USB charger can supply it or the use of wifi and gps whilst charging overheats it. I particularly see this behavior when I'm running tomtom and navizon. The phone seems to remain charging longer in cooler weather or if I point an air vent at it. My current no wifi woes started after an occurrence of just this behaviour the other day.
RAZR chargers don't have enough current and it doesn't keep a positive charge when using the GPS. It says it's charging but ultimately it goes down. Sometimes it stops charging and I had to unplug it and plug it back in. Use a charger made for the Kaiser. The charger from my brother's bluetooth GPS works fine though.
I have a generic USB cigar lighter adapter which I have been using to power mine with no problem. The only way I can see a charger frying a phone is if there is a voltage spike that isn't regulated.
The charger needs to be rated with an output of 5v 2amps which is what the electric charger is rated at. Bought one off ebay for $6. Most car chargers are rated quite a bit lower (400ma).
As the previous post states, some chargers are rated at under 500ma. This is not enough to change the Kaiser... I find that the Blackberry charger works fine, but sometimes takes a very long time to charge as the current isn't quite enough. I have a generic one at about 1000ma and that works fine.
USB from a PC is normally 500ma sustained.
I think there's another thread or 2 about this somewhere. I've been having the same problem with the Kaiser not charging via generic and razr car chargers.
After seeing the other thread I bought an HTC charger from ebay - at least it looks like one and is advertised as one! The sticker on the 'real' HTC charger only says 0.5 amp (same as the others are rated), but charges no problem with TomTom going.
I tried measuring the current using different chargers and PowerGuard and I think there is a definite difference (although not an easy thing to interpret). I notice the cable is significantly heavier on the real HTC charger (also coiled and tends to drag the phone from where I mount it a little). Others have said the pinouts are different too.
I looked for a 2amp charger but couldn't find one (if anyone knows a source?).
It's an intriguing problem but a 'real' HTC charger seems to fix it.
The other thread: http://forum.xda-developers.com/showthread.php?t=406771
There were a range of brodit car mounts with built-in chargers that bricked the kaiser. I bought one and it instantly blew it's fuse. I replace the fuse and it blew my kaiser up instead.
Assuming it was the kaiser I had it replaced, only for the charger to blow it up again.
Since then I contacted dsldevelopments (UK Distributor) who replaced it with an updated model. I have not had any issues after that.
I had this problem (Kaiser not charging in the car when GPS is on) and resolved it totally by getting the offical HTC car charger. Although output is 0.5A it is rated to 2A - my previous generic car charger was only rated to one amp and that would work fine as long I wasn't using GPS but once I ran GPS it just couldn't cope. Definately resolved this problem with the official HTC car charger (got mine of flea bay for £8)
cheers
Barney
I've had no problem with designed-for-Moto chargers and ones specifically designed to charge over USB from a dumb charger.
The problem is that drawing more than 100 mA without negotiating a connection with a PC violates the USB specification. Many manufacturers have gotten around this by finding other ways to signal the presence of a "dumb" charger, telling the phone it can draw more than 100 mA.
In the case of Mini-USB devices like the Motos, Blackberries, and HTC devices, the Mini-USB connector has a fifth pin that is normally not connected. If the charger plug grounds this pin, it signals to the device that it is permitted to draw more than 100 mA without a PC connection.
If you get a charger that does not ground this pin, an HTC device will not charge rapidly, if at all. (Typically only charges slowly when screen is off). This is why you get two cables when you order a single MiniSync from BoxWave, for example. They give you one "Sync and charge from PC" cable (no pin grounded) and one "Charge only" cable (pin grounded for dumb chargers). (If the pin is grounded it interferes with data communications for most devices.)
I use a motorola charger, which is fine if you do not use GPS.
when I use the GPS after some time the battery is very hot and stops load, but if I put the cell in front of the AC, just cools again to load.
I think the problem is due to protection from overheating battery
Belkin Charger
I grabbed a Belkin charger for my KRAZR/RAZR phones and it seems to work just fine, even with GPS running. My official Moto one also works fine with the tilt in GPS mode.
I do notice, though, that no matter what I'm using to charge it with, with GPS it gets hot. Since Li-Ion batteries are supposed to stop charging at a certain temp, it's possible that the combination of a lower grade charger and the heat generated by using GPS/WiFi/Cell at the same time (or any combo of the three), might be the issue.
Hi there!
My brother just bought me a spare battery. Well it still needs to be charged after usuage. The thing is I have to swap the batteries everytime I used them both. The solution is to buy a cradle to charge it but these are kinda expensive.
My solution would be to build my own charging cradle. But I lack the knowledge of electricity skills to succesfully making such charger without blowing up my battery. Therefor I'm asking the community on XDA for help!
Well this is what I need:
- Battery has 3 connectors: + and - and on in the middle but i dont know what that is.
- I have a usb cable with 4 wires (black/red/green/white)
- I want to connect the usb connecter to my PC or AC adapter and the wires to my battery.
This way I can charge both my HD2 and the spare battery at the same time.
The question is, is this possible and if yes, can this be done just like that or do I need transistors or conductors (or whatever they may called). It needs to be safe, I dont wanna blow up my battery or my AC adapter nor my PC...
Do not even contemplate it.
It is clear that you do not know enough about batteries.
A quick google for desktop chargers came back with one for only £30
For 25quid i got a spare battery, desktop charger and 2 screen protectors from e-bay. Carnt go wrong at that price
I know that the AC adapter converts the input of electrical energy to my phone, I believe my phone does it to my battery too (thats where I'm not too sure).
All I need to know is if I can charge the battery safely when connecting the red wire to the + and the black wire to the - side of the battery... (The green and white wires are data)
I'm not to sure because the AC adapter has a different output than the PC USB output. Although the USB dilivers a tiny bit less voltage it delivers a significant less amount of Whats (or Amps) Basicly that means it just takes longer for the USB to charge as long as the voltage remains identical. (The USB delivers less voltage but the effect on damaging the battery is minimal because the difference is discardable)
My actuall question was: can I connect my battery directly to the AC adapter or do I need to convert the electical energy again (if my phone does a second convert after the AC adapter).
You can find chargers on eBay for less than 5usd. Buy one or you will fry your battery.
VerusAmos said:
I know that the AC adapter converts the input of electrical energy to my phone, I believe my phone does it to my battery too (thats where I'm not too sure).
All I need to know is if I can charge the battery safely when connecting the red wire to the + and the black wire to the - side of the battery... (The green and white wires are data)
I'm not to sure because the AC adapter has a different output than the PC USB output. Although the USB dilivers a tiny bit less voltage it delivers a significant less amount of Whats (or Amps) Basicly that means it just takes longer for the USB to charge as long as the voltage remains identical. (The USB delivers less voltage but the effect on damaging the battery is minimal because the difference is discardable)
My actuall question was: can I connect my battery directly to the AC adapter or do I need to convert the electical energy again (if my phone does a second convert after the AC adapter).
Click to expand...
Click to collapse
Watts not Whats
Simple answer: No you cannot connect your battery directly to the AC adaptor.
Detailed answer:
The USB port of a computer/AC adaptor provides approx 5V and a variety of currents depending on what the USB lead is plugged into.
This 5V goes to the phone.
Inside the phone is the battery charging circuit, this detects the level of charge in the battery, controls the voltage and current going to the battery to stop it releasing too much hydrogen which would cause the battery to swell and explode (look on youtube for lithium polymer battery fires).
If you think you can create a charging circuit (including selecting the right ICs and programming them) without burning yourself in a hydrogen/lithium fire, be my guest.
Incapable of making an external battery charger...
Here I am trying not to be a complete idiot and then I go and spell watts the wrong way...
But tnx for the replies, that was all I needed to hear... I guess I'll be swapping batteries after all untill I find a cheap external battery charger...
Cheers!!!
Amzer makes a very nice cradle with charging slot for your spare battery. I got mine for $28USD. I'm not going to provide the link to the outfit I bought mine from because they weren't the best of suppliers to buy from. But the Amzer cradle works very well. Downside is that you cannot use it if you have a case for your Leo that wraps around it, and is designed to stay on. Leo must be caseless to fit into the cradle. But even if you don't use the cradle as a cradle, it does have the ability to charge your spare battery.
Iam using the Dell Streak 7 as a sat nav system in the car. Ive tried to charge it up on the usb car adapter but it seems to loose its charge over time, making the D7 unusable for the purpose of a sat nav. Am i doing something wrong or is there a special usb car adapter for the job?
Thanks, David.
Does it say it's charging when plugged in?
Depending on how powerful your charger is it's likely that it's draining faster then the charger can provide. At best on my s5 it's just barely faster then the charger and the s7 needs more power then that.
Thanks for peply, yes it states it is plugged in. I came to the same conclusion. Wonder if there are any other chargers that have more juice.
diddy64 said:
Thanks for peply, yes it states it is plugged in. I came to the same conclusion. Wonder if there are any other chargers that have more juice.
Click to expand...
Click to collapse
There are several that will do the job. Just look for specs that include putting out 5.5 volts and 2 amps. Several of the chargers that are made for the iPad2 will work. And you may want to install a lighter adapter that you can wire directly to the battery that will allow up to 2 or 3 amps from each port
Most standard USB ports do not put out enough power to charge the DS7. The best bet is to use a inverter that plugs into your cigarette lighter and then plug the charger into that, not just the USB cable.
http://www.amazon.com/Power-Inverter-Charger-Portable-SmartPhones/dp/B00144KS6W
I use this setup:
Bestek Adapter
Trans4m lighter adapter
The Bestek I have wired to the battery so I have no fuse problems with lighter, and with that I can charge either my iPad2 or my Streak7, IF I need to charge both, then I plug the Transform adapter into the Bestek and can then charge BOTH devices, the Ipad2 AND the Streak7 and a couple of other things if need be
Thank you guys, this gives me alot of hope. Once again you all get my thanks.
Cheers,
David.
Yea, like they previously stated not all chargers are created equal.
Unless it states it's a tablet/ipad charger you cant assume it's doing 2+ amps. Most phone/lower end ones can only do 500mA/1A.
Realistically you'd prob need at least 2 amps to get a net gain while using gps/anything demanding. But I dont know if it would even try and draw above that if given the chance. [email protected] is what the bundled wall charger does and can accept up to 5.5v (as it's still within the +/-10% tolerence of the usb spec, but just barely)
My fully charged stock S7 WiFi running 514 draws only 45-70mA. Maybe starting fully charged would help?
wptski said:
My fully charged stock S7 WiFi running 514 draws only 45-70mA. Maybe starting fully charged would help?
Click to expand...
Click to collapse
I don't know anything about how it works, but I imagine tablets are wired to know when they are receiving the correct amount of input. For instance, if you connect your Streak 7 to a powered USB hub that only puts out 5 volts, it won't charge nor will it charge when connect via usb to the PC, it has to be receiving 5.5 volts and 2 amps before it will let itself receive charge. I have an iPad that is the same way and have noticed all the tablets I have had my hands on are the same, Galaxy Tabs, Transformers, Xoom... all those have to receive higher numbers to charge. So you have to have a cigarrette lighter adapter that puts that out, if it's for a cell phone it won't do anything for it
cdzo72 said:
I don't know anything about how it works, but I imagine tablets are wired to know when they are receiving the correct amount of input. For instance, if you connect your Streak 7 to a powered USB hub that only puts out 5 volts, it won't charge nor will it charge when connect via usb to the PC, it has to be receiving 5.5 volts and 2 amps before it will let itself receive charge. I have an iPad that is the same way and have noticed all the tablets I have had my hands on are the same, Galaxy Tabs, Transformers, Xoom... all those have to receive higher numbers to charge. So you have to have a cigarrette lighter adapter that puts that out, if it's for a cell phone it won't do anything for it
Click to expand...
Click to collapse
The voltage is constant but current isn't. It won't know how much current is available unless it asks for it. It's like a 2A fuse, you can draw up to 2A, no more.
Even with a fully charged battery it'll show charging at 98% for a short time and that's when I saw the higher 70mA but I'm not sure if it's in the CC or CV part of a Li-Ion charge cycle but I'd guess CV because it's less than 100mA.
My bad thinking measuring AC input current instead of DC current since this thread is about USB power.
Used a cheap ReTrak USB extension cord that loses connections to seperate the wire to measure DC current. My fully charged S7 showing 100% charge still draws 150mA after hours of being plugged in. Since Li-Ion cells normally don't use a constant trickle charge, I "assume" something draws on the battery all the time along with the indicator light and buttons.
Booting up it draws a little over 1A, fully charged while booted up, it draws around 600mA. While charging and powered up, it draws 914mA. Charging while off, it draws 1160mA. Far from 2A.
wptski said:
My bad thinking measuring AC input current instead of DC current since this thread is about USB power.
Used a cheap ReTrak USB extension cord that loses connections to seperate the wire to measure DC current. My fully charged S7 showing 100% charge still draws 150mA after hours of being plugged in. Since Li-Ion cells normally don't use a constant trickle charge, I "assume" something draws on the battery all the time along with the indicator light and buttons.
Booting up it draws a little over 1A, fully charged while booted up, it draws around 600mA. While charging and powered up, it draws 914mA. Charging while off, it draws 1160mA. Far from 2A.
Click to expand...
Click to collapse
I understand that, but you are missing the point, if the internal wiring of these tablets don't receive the 2A they want they WILL NOT even begin to charge. I tried literally dozens of chargers when I first got my S7, spent a couple hundred bucks actually, and none of the chargers not meant for larger devices won't work, and what those chargers all had in common, 2A output
The S7 can and will draw off low capacity ports, it just wont admit to charging unless it's at least 1A as it's just that.
I've had my S7 charge off a 500mA port on my pc at the rate of like 1%/hour while sleeping. As it's barely gaining even while idleing it's not really charging in the literal sense, but it's definitely charging in the technical sense.
Are your data lines shorted together? I believe most high draw devices wont attempt to pull 2A unless it detects that it's on a high draw charger (which I think do this to indicate it as such)
cdzo72 said:
I understand that, but you are missing the point, if the internal wiring of these tablets don't receive the 2A they want they WILL NOT even begin to charge. I tried literally dozens of chargers when I first got my S7, spent a couple hundred bucks actually, and none of the chargers not meant for larger devices won't work, and what those chargers all had in common, 2A output
Click to expand...
Click to collapse
I don't know why your various chargers didn't work but it doesn't seem to be because of current. It didn't charge at 2A or even close to that.
If what your saying correct, why was I able to charge at less than 2A then? Could this be a ROM issue? I only had Froyo for a few hours but I've read that it didn't support USB charging which came with HC but it only charges with the S7 OFF.
It's possible that the demand went higher and I just didn't see on my current clamp meter. I'll have to try a current clamp and a scope to see if I missed a peak level.
Also what we are refering to as the charger might not be a charger but only a power supply and the actual charging circuit is in the S7.
I did notice one odd thing though. The green LED lights up at around 90% battery level and it's still charging. I downloaded a battery app which read the same level.
wptski said:
I don't know why your various chargers didn't work but it doesn't seem to be because of current. It didn't charge at 2A or even close to that.
If what your saying correct, why was I able to charge at less than 2A then? Could this be a ROM issue? I only had Froyo for a few hours but I've read that it didn't support USB charging which came with HC but it only charges with the S7 OFF.
It's possible that the demand went higher and I just didn't see on my current clamp meter. I'll have to try a current clamp and a scope to see if I missed a peak level.
Also what we are refering to as the charger might not be a charger but only a power supply and the actual charging circuit is in the S7.
I did notice one odd thing though. The green LED lights up at around 90% battery level and it's still charging. I downloaded a battery app which read the same level.
Click to expand...
Click to collapse
You were able to charge because your charger was CAPABLE of outputting 2A at least... try charging with one that CAN'T put that out and you should find that the Streak will not charge, on ANY ROM has been my experience, custom or stock
cdzo72 said:
You were able to charge because your charger was CAPABLE of outputting 2A at least... try charging with one that CAN'T put that out and you should find that the Streak will not charge, on ANY ROM has been my experience, custom or stock
Click to expand...
Click to collapse
Capable is the magic word here. The wall wart isn't putting out 2A from what I've seen, unless it does for a split second at the start which I'm going to look into.
Most wall warts at whatever their rating is put out a higher voltage with no load and slightly higher than its marked voltage under a load. If it required [email protected] max., you used a [email protected], S7 needs more current, the voltage would decrease. What's been stated here might be that the voltage was being pulled down and that's why the S7 wouldn't charge, not "really" the 2A issue.
I have a battery pack/cell load testing device used on RC stuff that connects via USB port for its graphic software. There were issues with certain Dell laptops that had a low voltage at their USB ports.
Maybe starting fully charged would help?
I have the OEM T-Mobile car charger and I've found that if I have a full charge before plugging the Streak into the charger it maintains a full charge for as long as I'm driving/using it. Otherwise, with a less than full charge I've watched it slowly discharge even though it's plugged in and is charging.
FYI: I also have a top of the line car charger for an iPad2 that charges the iPad no matter what charge level I plug it in. This iPad charger has a USB port which I have plugged the Streak USB cord into and it also doesn't keep up with the Streak's discharge if the Streak isn't a full charge to begin with. Kind of strange because I would think the iPad would draw more than a Streak. (the iPad isn't plugged in at the same time the Streak is charging)
DCoop said:
Maybe starting fully charged would help?
I have the OEM T-Mobile car charger and I've found that if I have a full charge before plugging the Streak into the charger it maintains a full charge for as long as I'm driving/using it. Otherwise, with a less than full charge I've watched it slowly discharge even though it's plugged in and is charging.
FYI: I also have a top of the line car charger for an iPad2 that charges the iPad no matter what charge level I plug it in. This iPad charger has a USB port which I have plugged the Streak USB cord into and it also doesn't keep up with the Streak's discharge if the Streak isn't a full charge to begin with. Kind of strange because I would think the iPad would draw more than a Streak. (the iPad isn't plugged in at the same time the Streak is charging)
Click to expand...
Click to collapse
The S7 must run some check before it tries to charge . Whatever it is the OEM supplied power supply passes the test.
What's the specs on your two power supplies?
Just remember if you dont have the same 2A for charging in the car. You cannot charge the streak while its TURNED ON. Same with USB charging, just turn the streak OFF, then charge. It will work. =)
Otherwise, Id get a DC to AC converter for the car, plug in your normal adapter.
Background
Hi all, I, for a very short period of time was suffering from the problem of my phone DISCHARGING while it was charging. This made no logical sense to me until I did some research, which I will detail below.
How USB Power works (Roughly)
Firstly let's discuss USB power provisioning. Strictly speaking, the specifications say that any given USB port should provide a maximum of 500mA (or 0.5A) at 5 volts. *Don't shoot me electronics guys, I'm simplifying for ease of explanations sake*. Imagine that ampage as the actual force of the charger, how quickly it can ram power into your phone. Like the rate of flow on a pipe.
The beginning of the problem
This was all fine and dandy when all USB was really used for was Keyboards, Mice, Memory, etc, low current draw devices. Something else I should mention here is that the Ampage that a port CAN provide is not the Ampage it DOES provide - the device draws a certain Ampage and if the USB controller agrees it outputs said Ampage. Later, when USB was beginning to be used for more power hungry applications, ie External hard drives, these required more power than the port could (In theory) provide. However, most more modern motherboards/USB controllers were more than capable of supplying plenty more Ampage if it was requested. This was breaking the specification but not in any massively dangerous way so as such nothing bad happens.
This is where we get to the actual issue people are experiencing here. The Nexus 4 is a standards compliant device in the respect that it seems to only draw 500mA from any USB port no matter what it's potential, unless it's an AC Wall wart. If you're experiencing problems with wakelocks (see XDA) and other things, this causes your phone to draw more than 500mA which means your phone actually discharges while it's charging! Terrible!
This is quite easy to get around, but again I'm going into detail so let's explain how the phone tells the difference between a dumb wall wart and a USB controller. Easily! The USB controller obviously makes use of the data pins found within the USB cable, whereas a wallwart just (almost always) shorts them out. The Nexus 4 can detect this short, and as such draw more power *While still in quotation marks staying in spec*.
The root problem is not with how the N4 is charging, it's with the wakelock you're experiencing which is causing the phone to draw so much power while the screen is off. While the screen is off and the phone is in Deepsleep (A CPU state where it uses very little power) - it should draw no more than 50mA leaving 450mA for charging the battery, but you guys are probably experiencing a wakelock of some sort.
Solutions to the problem or How to break a specification for the good of mankind
The simple solution is to install this app: https://play.google.com/store/apps/details?id=com.rootuninstaller.batrsaver
This forces the device into a Deep sleep when the screen goes off by killing applications and turning off all internal chipsets that have wakelock capability, most commonly networking on the Nexus 4. This will allow your phone to charge (slowly) off USB without an issue. Another common wakelock is when the device is picked up by your desktop as a media device. The USB controller inside the Nexus 4 forces a wakelock which keeps it from charging. Stupid design, I know.
* A more hackish solution is to install Francos kernel, buy his app, and tick the Fast charging option in the kernel settings dialog. This will force the phone to think that everything is an AC adaptor and will force the phone to draw as much current as it can from the USB port (which on most modern motherboards is fine, and results in extremely quick charging).
* An even simpler solution than all this is to just use a 'USB Charging cable' - this is simply a cable that does not have the Data pins, and as such does exactly the same as what enabling USB fast charge above does. http://www.ebay.co.uk/itm/Micro-USB...487076?pt=PDA_Accessories&hash=item51a465d124
If you live near a Poundland store here in the UK they sell a 4 in one USB cable type thing which turns 1 USB port into Ipod sync connector, Nokia connector, MicroUSB and MiniUSB, and this doesn't have the data pins and as such is excellent.
One final point, an excellent app for monitoring whether your device is actually charging or not and how quickly is Current widget: https://play.google.com/store/apps/details?id=com.manor.currentwidget&hl=en
This widget will tell you how much Ampage is going into or leaving your battery. If the battery icon is green, then it's discharging, if it's black/white then it's charging. The bigger the number, the faster the discharge/charge. This is an extremely easy way to test speed of chargers too.
Recommendations
Another solution, just use an AC Wall wart - they're cheap as hell and the one supplied with the Nexus 4 is an extremely fast charging one. Shame I've gone and lost mine.
A way to roughly monitor charging current draw
I'd also recommend you install https://play.google.com/store/apps/details?id=com.manor.currentwidget&hl=en and monitor, if the battery is green while charging it's discharging and you need a more powerful charger/to figure out what's causing your phone to use so much power.
General good values in Current Widget
I generally saw a max draw of about 750mA for charging (not including draw for powering the device, the Nexus 4 can draw more power to charge and power the device) on my old Rev10 first generation Nexus 4. On my new Rev12 board I'm noticing this increase to about 850mA.
Are higher amperage chargers any benefit to anyone?
Yes and no. You will not notice faster charging unless you use your device while charging. Your nexus will draw as much power as it needs to power the phone while charging at the fastest rate. For example on the stock 1.2a charger
1200mA | 800mA goes to charging 400mA goes to powering the phone idling
Let's say you start a stability test. Your phone will obviously be using a lot more power so this will happen
1200mA | -600mA goes to charging and 1800mA goes to powering the phone stability testing
That minus value above may look strange! Let me explain. If the phone needs more power than the charger can supply, it will draw from the battery. That's the minus number.
If you have a higher ampage charger like for example a 2.5a charger
2500mA | 800mA goes to charging 400mA goes to powering the device
Stability testing
2500mA | 700mA goes to charging 1800mA goes to powering the device
Can you see the difference?
DISCLAIMER: I am not an electronics engineer nor do I claim to be, I am simply a hobbyist and this is what I've found to be the case. Please correct me if I've made any mistakes, I want to learn.
Thanks!
Thanks so much for this post. It's very helpful.
kn100 said:
Another common wakelock is when the device is picked up by your desktop as a media device. The USB controller inside the Nexus 4 forces a wakelock which keeps it from charging. Stupid design, I know.
Click to expand...
Click to collapse
This isn't true for everyone then as mine connects and charges just fine off of my laptop and desktop when connected as a media device. In fact its on my laptop right now charging, gone from 68% to 81% in about 30 minutes and it shows connected as a portable media player.
Great info! Thanks for writing this!
In certain use cases the Nexus4 discharges faster than it charges and this is a very useful guide.
I use my phone for navigation in my car and having the GPS on and the screen at high brightness
drains the battery faster than the 0.5A car chargers can supply. Car chargers rated for 2.0A work well.
I haven't tried a 'USB charging cable' with the data pins shorted, it may work as well.
-Mindroid- said:
Great info! Thanks for writing this!
In certain use cases the Nexus4 discharges faster than it charges and this is a very useful guide.
I use my phone for navigation in my car and having the GPS on and the screen at high brightness
drains the battery faster than the 0.5A car chargers can supply. Car chargers rated for 2.0A work well.
I haven't tried a 'USB charging cable' with the data pins shorted, it may work as well.
Click to expand...
Click to collapse
was over in Nexus 7 forums and the 4.2.x kernel should have solved the problem at least for having to use shorted cables. have to wait and see if 4.2.2 brings any more changes.
http://forum.xda-developers.com/showthread.php?t=1984838
Section 6 in this link is about power supplied through USB
http://en.wikipedia.org/wiki/Universal_Serial_Bus
I can't tell if we have an updated kernel allowing faster usb charging as I'm limited by the power output of the usb port in my laptop. The output (5V at 500mA max) is controlled by the laptop (USB Standards) and it doesn't matter what the phone or cable is capable of as that's the max it will give out and that's about what I'm charging at. If I had a dedicated charging port in my laptop then it would be different and I could see if its able to draw more power. I have a 1.0 amp port in my car and it does charge at the higher amperage, I would assume it would do the same thing if I had a 2 amp usb port in the car. So I think the stock kernel has the fast usb charge built in it just depends upon if you have a usb port capable of providing a faster charger, it has nothing to do with the cable as I'm using a standard unmodified micro usb cable and its able to draw the max a usb device is able to put out.
thanks
thanks for a great detailed post!!!
I have the same trouble with my N4 when I was charging while using my phone...
I find it very slow... I guess I've been spoiled by my previous iPhone (which charges fairly fast)....
i might be stating the obvious but I find the phone charged "a lot" faster when it's OFF
if you are running low with your battery and need a quick 10 min charge, just do yourself a favour by turning off your phone...
the difference is quite significant!
kzoodroid said:
This isn't true for everyone then as mine connects and charges just fine off of my laptop and desktop when connected as a media device. In fact its on my laptop right now charging, gone from 68% to 81% in about 30 minutes and it shows connected as a portable media player.
Click to expand...
Click to collapse
Yup, me too. It only discharges while charging when I am playing like NFS most wanted.
Sent from my Nexus 4 using xda app-developers app
The issue with cables is with the LG usb wall charger as the one supplied isn't capable of getting the 5 volts at 1.2 amps that the charger is rated at, mine is getting around 300 - 400 mA. The micro usb cable I have in my car and use with my laptop (for charging and data transfer) is able to handle the higher amperage, it gets around 1 amp with the LG plug. There are no specs on these cables so I can't list a definitive difference and I would assume that the cable mod in the OP might help with the LG cable. It also might just be simpler to only buy those cables capable of handling higher amperage as obviously they are out there from my experience.
The cable I'm using is an RCA coiled charging/syncing cable model AH732CBR (has data pins). The maximum I'm getting from this is about 870 mA regardless of the amperage of the usb port, I've tried a 1.0, 1.2 and 2.1 and they are all around 870 mA on current widget. I would suppose if I could find a strictly charging cable I could get higher (link to ebay in OP is outdated) but this is still 2x that which I'm getting from the LG cable supplied with the phone which only puts out 300-400 mA. Our phone also has Qualcomm's quick charge which is supposed to improve battery charging times by 40%.
http://www.droid-life.com/2013/02/1...allows-your-device-to-charge-up-to-40-faster/
How do you measure how much mA the device draw from the charger?
Sent from my Nexus 4 using Tapatalk 2
omrij said:
How do you measure how much mA the device draw from the charger?
Sent from my Nexus 4 using Tapatalk 2
Click to expand...
Click to collapse
current widget, link is in the OP
kzoodroid said:
The cable I'm using is an RCA coiled charging/syncing cable model AH732CBR (has data pins). The maximum I'm getting from this is about 870 mA regardless of the amperage of the usb port, I've tried a 1.0, 1.2 and 2.1 and they are all around 870 mA on current widget. I would suppose if I could find a strictly charging cable I could get higher (link to ebay in OP is outdated) but this is still 2x that which I'm getting from the LG cable supplied with the phone which only puts out 300-400 mA. Our phone also has Qualcomm's quick charge which is supposed to improve battery charging times by 40%.
http://www.droid-life.com/2013/02/1...allows-your-device-to-charge-up-to-40-faster/
Click to expand...
Click to collapse
Bit of a late reply but please bear in mind the Nexus will NOT draw anything more than about 800mAh from the wall for charging alone. That is the absolute max and is a hardware limit - If the cable is transmitting that and it's showing in current widget you've got a good setup. See the added section in OP for more info on higher amperage chargers.