Decided to make a seperate thread for this. Maybe a mod could move those posts over...
scoob8000 said:
This is very interesting.. Gonna order one of those adaptors. I have another possible source that I'll call and see if they can get them.
Dx rocks but I lack the patience to wait for overseas shipping.
Food for thought..
I have a cheapo 4 port usb hub on my night stand for charging all my devices. It is limited to 500ma per port. Ive noticed it won't charge my atrix. Guessing 500ma isn't enough..
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Click to collapse
Rred said:
scoob-
"It is limited to 500ma per port. Ive noticed it won't charge my atrix. Guessing 500ma isn't enough.."
No, physics doesn't work like that. If the VOLTAGE from your USB device is above the charging voltage for the phone, even a 100mA charger would be enough to charge the phone up. It would just take a long time, perhaps 22-24 hours to do so.
The normal Moto chargers are about 1000mA and they charge the phone quickly, usually two hours or less. But Moto has been making very generous chargers for years, they even supplied a 1000mA charger with my bt earpiece, which doesn't need that much power at all.
If a 500mA charger hasn't fully charged your phone in 4 hours, there's something else wrong. Bad wire, bad contact, not plugged in tight...or the "Made in China" effect.<G>
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Click to collapse
_Dennis_ said:
No you are wrong sir. The phone will not charge on a 500 ma charge. It will use less battery but 500ma charger is not sufficient to both power the device and charge it. Also the charger supplied it 750ma charger and if you are running 1.2.6 the phone will refuse 1a chargers. Just because something provides voltage in the correct range does not mean ut provides enough energy to charge something else. Voltage is potential current is actual power. Just plug your phone into a USB socket without the computer having drivers (there by limiting the socket to 500ma) it won't charge.
Sent from my MB860 using Tapatalk
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Click to collapse
scoob8000 said:
Sorry OP for the threadjacking..
I'm familiar with Ohm's law, where I was headed is I think the phone may be doing one of two things. (purely guessing )
It may just be adhering to USB specs. It realizes the hub is a USB device and not just a charger. Since there is no computer on the other side, to negotiate more than 100ma it just doesn't charge.
Or the voltage drop @ 500ma (my hubs max per port) is just too high to enter charging. Worth noting, is when the battery is >90 and I plug the hub in, the notification led lights, but the battery still discharges.
I need to hack up a usb cord to take some voltage/current measurements. Maybe I'm just being OCD, but I like to "slow charge" my devices while I sleep.
[edit] I think I'm going to try making a charge only USB cable... That might answer some questions
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Click to collapse
Rred said:
Dennis?
"It will use less battery but 500ma charger is not sufficient to both power the device and charge it."
Powering the phone, and charging the phone, and simultaneously doing both, are three different things.
The 500mA is sufficient to CHARGE the phone, that's all I said. I have no idea how much power it takes to POWER the phone with all four radios (BT, GPS, Wifi, cellular) active and music or Angry Birds playing at the same time. The power drain for each of those may be significant.
But since the phone has a ~1900mAh battery, you can establish the phone's power drain by turning on "everything" and letting the battery drain from full charge. If it takes four hours to go dead...yes, the phone may consume 500mA all by itself, leaving nothing to charge the battery. Again, that's physics, and it applies the same way to every laptop and phone on the market, and other devices that use adapter/chargers.
I stand by what I said: 500mA will fully recharge the battery in about 4 hours. I did NOT say it would power all four radios and play music as well as charging the phone at the same time. You'll have to do your own math to find that out, but the physics remains the same. My phone usually charges while I sleep, and a 500mA source will do that very nicely, with just the cellular radio enabled, and not in conversation.
Click to expand...
Click to collapse
So I just made a little USB breakout cable so I could do a little investigation..
Oddly, even with the stock charger and the data lines disconnected the Atrix will not charge. I'm supecting most AC chargers must supply power on the data lines as well, or do something with them that triggers the device to charge.
As for the voltage, my hub and oem charger both throw out 5.12v with no load. When I plug the phone in, there is no drop at all.
From what my googling turns up, I may need a 180ish ohm resistor between the data lines. The phone looks for that to enter charging mode. Apparently this is why the drivers are needed for charging on some computers. Instead of resistance, it gets the charge signal from the pc.
So anyway out of curiosity I also took a few load readings:
Battery at 40%, screen off, phone idle: 600~ma
The most I could get it to pull was with battery at 40%, streaming last fm over a BT headset, and running quadrant. I saw around 690ma at peak.
Voice calls don't seem to make much of a difference. 10-15ma.
I'm going to check again with a full battery once it's charged. That ought to tell us what the phone itself is using.
I'm using a 550ma 5v charger because it has a longer reach. I stream music, cruise the net, watch videos and it charges my phone no problem.
Sent from my MB860 using XDA Premium App
So with a completely full battery:
Idle, screen off: 100~ma
full load (same as before): 400ma at peak
Either I am lucky and got a better one, or everyone else is wrong on the standard charger. Mine is 850ma. Also, my phone will charge on USB 2 (500ma) if screen is off and I do not use the phone. It's slow but it charges. On USB 3 it charges about half the speed it does on mains.
Sent from WinBorg 4G via XDA premium app
scoob-
"As for the voltage, my hub and oem charger both throw out 5.12v with no load."
Were you using a lab calibrated voltmeter? <G>
Most digital multimeters have a stated accuracy something like 1/2 to 1% on the DC voltages, and then they also have a "float" of 2-4 LSD meaning, the least significant digit (the rightmost one on whatever scale) may float by 2-4 digits.
So on a typical meter where you have a choice between a 2.000 volt scale, and a 20.00 volt scale, "_5.00" on the display could just as easily read "5.05" if it is was 1% off, within the limits of accuracy. And then 5.05 could read 5.09 or 5.00 as the digits float. The errors sometimes cancel out, sometimes accumulate.
I've seen much worse as they get old and out of calibration, where a "12.00" volt reading on one meter was 12.3 on another.
Which is just to say that 5.12 might actually be 5.00, or whatever the USB spec actually calls for. (It doesn't have to be 5.00 exactly.)
I had no idea they needed a signal voltage (available from the data lines on microUSB but not miniUSB) to enter charge state. That "should" mean that you can't use a miniUSB charger with a micro adapter for simple charging. I'll have to try that to see what happens. [ [LATER] Nope, something's not right about needing the signal resistor, because I just charged my Atrix using a miniUSB charger (no data signal possible) with a mini-to-micro power tip adapter, which "should" not be presenting any signal, just passing through the 4 old style connections. ]
There will still be simple--if unpublished or poorly documented--rules of physics governing what happens. Battery charging isn't rocket science, although battery chargers are sometimes "smarter" than rockets are.<G>
CaelanT,
Mines also 850ma..
Rred,
I actually splurged on a very (I think) good meter a few years ago. It's a Fluke 187. They claim .025% DC accuracy. Granted, I've had it a few years and never sent it back in for calibration.
I actually found two sides to having a resistor in the connector.
One story starts with Motorola trying to enforce people using only "genuine" chargers. Link
The other points to the data lines being shorted to indicate to the device that it is a dedicated charging device. Link Skip to the last paragraoh on this page. It's very long winded.
I actually tore apart a old car charger, in the mini usb plug there lied a small resistor between the data pins. I didn't believe how simple it was until I saw it.
Pretty interesting stuff. For us geeks anyway.
scoob, a Fluke is like a Rolls-Royce, except it is more reliable.<G>
The resistors are documented as part of the microUSB spec, they are what are often called "pull-up resistors", i.e. the voltage they provide to the fifth wire "pulls up" the voltage on that line and the tiny brains see that as a signal to do something specific.
Even the Palm Treos used this system. Not on the power line, but on the audio jack. they use a single 3-wire 2.5mm standard minijack and depending on the impedances that they see on it, they will provide mono audio, stereo audio, or mic input plus mono audio, so that three types of devices all plug into the same plug--but all three are sensed and work differently. As Arthur Clarke said "Any sufficiently advanced technology will be indistinguishable from magic."
There's no Moto conspiracy to the resistors, the new microUSB spec provides magic and the industry just doesn't want to bother our pretty little heads by talking about it in any detail.
Now, why Moto omitted the call audio routines from the library on these phones...THAT'S probably a conspiracy.<G>
I'm not reading all 480+ pages of the final USB3 spec, but it appears to refer to standard devices as consuming one "unit" of power at 150mA, with a maximum of six "units" or 900mA, and a maximum voltage of "5" which would mean that if Moto is supplying 5.12V @ 1000mA...they've exceeded the spec and aren't entitled to use the USB logo.
But if they'll fix my call audio library, I won't tell a soul about that.<VBG>
Related
I have been pondering...
Our phone is awesome in every aspect.... battery life is between 6 hrs ~ 7 hrs depending usage...
However... charging the battery seems to take FOREVER !!!!!!!!
it takes like 5+ hours to charge completely
if you want to charge it faster, wireless, phone, screen, etc needs to be off.
so that's the only inconvenient thing i found about our phone.
good thing is i can plug it in anywhere it has USB ports, including my car.
Make sure you use the correct charger. Many chargers that use the same socket do not charge at the same rate as the correct one due to internal wiring - I am not electrician but found this out the hard way.
Many USB/car chargers do not provide sufficient charge to even keep up with Athena power use.
AllGamer said:
I have been pondering...
Our phone is awesome in every aspect.... battery life is between 6 hrs ~ 7 hrs depending usage...
However... charging the battery seems to take FOREVER !!!!!!!!
it takes like 5+ hours to charge completely
if you want to charge it faster, wireless, phone, screen, etc needs to be off.
so that's the only inconvenient thing i found about our phone.
good thing is i can plug it in anywhere it has USB ports, including my car.
Click to expand...
Click to collapse
The SIZE matters... also in charging.
May be I am wrong, other in this forum are better than me in physic
but
1) The power usage when connected via activesync, having screen backlight 50%, Big HTC HOME is around 200/300 mA/h.
2) The battery is 2200 mA,
3)if you charge it with a 500 mA/h charger... 500-250=250 mA/h.... 9 ours to have a full 2200 mA charge,
Athena have also XSCALE CPU (clock increasing during heavvy usage) and the power usage could increase very quickly (I have seen some 1000 mA/h peak) due to heavvy memory and CPU usage, or microdrive access
Looking at DIVX movies, full screen, USB 1.0 connected... the power DECREASES (slowly)!
And I would like to add, that after several tests with different chargers, no doubt that using HTC chargers makes a big difference, specially the car charger.
In the case of car charger, using a normal one ( output 5V 500mA ) I made a trip of 300Km and the power level went down from 100% to 70% using TomTom.
And with the HTC charger ( 5V 2A ) leaving home with 50% and arriving the same destination with 100%, again using TomTom.
I'm assuming that using other GPS software the results will be equal.
I used car chargers with 500mA, 800mA and also 1A and I tought that the results should be different but in fact it seems to me that one thing is what the charger "says" and another thing is what can "give".
hope this helps.
poppey said:
.. it seems to me that one thing is what the charger "says" and another thing is what can "give".
hope this helps.
Click to expand...
Click to collapse
Yes, as I said it is a hard-wire issue
Yup, 2 pins need to be connected together before the Athena will go into "fast charge mode". You could hook up a 1000 amp bench power supply but still discharge your battery with GPS active - until you short the 2 pins. Don't remember which ones, its been discussed before on this board.
very insteresting...
yes i'm using the USB 500ma charger, just because past experiences has kind of though me that charging electronics with too much AMP it can burn it.
but it seems like the ATHENA can take that, since you have been using it.
I guess i'll shop around for a more powerful charger.
poppey said:
And I would like to add, that after several tests with different chargers, no doubt that using HTC chargers makes a big difference, specially the car charger.
In the case of car charger, using a normal one ( output 5V 500mA ) I made a trip of 300Km and the power level went down from 100% to 70% using TomTom.
And with the HTC charger ( 5V 2A ) leaving home with 50% and arriving the same destination with 100%, again using TomTom.
I'm assuming that using other GPS software the results will be equal.
I used car chargers with 500mA, 800mA and also 1A and I tought that the results should be different but in fact it seems to me that one thing is what the charger "says" and another thing is what can "give".
hope this helps.
Click to expand...
Click to collapse
AllGamer said:
charging electronics with too much AMP it can burn it.
Click to expand...
Click to collapse
Not true. Electronics is in many ways like the water system, with the water pressure equal to volts, and the gallons per minute equal to amps. However, there's one key difference - electronics will only use as much as its needs (and no more). Not like trying to get a drink from a high-pressure fire hose where you'll hurt yourself trying.
A 60 watt light bulb will only draw 60 watts and will not blow up even though it could draw many thousands of watts before the circuit breaker blew.
techntrek said:
Yup, 2 pins need to be connected together before the Athena will go into "fast charge mode". You could hook up a 1000 amp bench power supply but still discharge your battery with GPS active - until you short the 2 pins. Don't remember which ones, its been discussed before on this board.
Click to expand...
Click to collapse
This seems to do the trick with my Ameo.
http://www.expansys.com/d.aspx?i=154871
Hey! Guys I am having problems with the USB Charging, it seems to drain the 100% charged battery quicker (while using the phone, unplugged NOT charging) like one day and I have to charge the phone again, But when i charge my phone (100% charge) using the wall charger my phone lasts two and a half days. My wife also said she experiences the same thing with USB charged HTC Trinity Phone. I have tried on different computers and laptops as well but still the same and i know that USB charging will take longer to charge (500mah) so i leave the phone over night like 9 hours but the phone drains like juice. What kind of a Phenomenon is this.. Guys i need your humble thoughts and solutions on this because this is becoming a big problem for me since i use USB charging mostly... Plus I am not a very hardcore app, wifi or games user on the phone either... Darn...
same problem
I don't know why but i meting with the same problem. No idea why this happening it should be same from electric perspective.
When the phone cahrges via computer USB, the phone charges at a rate of around 90mA due to the phone running. Try with the phone off
Tried that as well, but it seems to be the quite the same but little difference since it last a little longer but still drained out in one freakin day. I am pulling my hair off because of this problem.. darn why is this just so... i mean like in the second post the process should be electronically identical right. only difference is it takes more time to charge from USB.... Grrrrr!
my phone hardly last one day..How do you make it last for 2 1/2 days?
xiyan2127 said:
Tried that as well, but it seems to be the quite the same but little difference since it last a little longer but still drained out in one freakin day. I am pulling my hair off because of this problem.. darn why is this just so... i mean like in the second post the process should be electronically identical right. only difference is it takes more time to charge from USB.... Grrrrr!
Click to expand...
Click to collapse
Battery indicators do lie.
it all depends upon if your board can deliver enough current to run the phone and charge it. on my rig i see no difference between wall charger and laptop or desktop charging
the laptop is a studio 15 with an i5 and h55 chipset and the desktop is a core 2d machine with a p45 series chipset.
you can tell the phone to disable usb charging if the phone is on while connected to usb to see if that helps (it will still charge via USB if the phone is off)
anhyeuemmaimai said:
it all depends upon if your board can deliver enough current to run the phone and charge it. on my rig i see no difference between wall charger and laptop or desktop charging
the laptop is a studio 15 with an i5 and h55 chipset and the desktop is a core 2d machine with a p45 series chipset.
you can tell the phone to disable usb charging if the phone is on while connected to usb to see if that helps (it will still charge via USB if the phone is off)
Click to expand...
Click to collapse
any usb not from china will give about 500mah, whether it be my i7 laptop or z550 vaio, so specific components shouldn't matter.
usb charges a little slower, but no reason it should not last as long once its got all the amps it can take. weird situation man...my huge list of htc phones never had an issue, and i do use a work computer to charge via usb sometimes
Thanks for your thoughts guys!!!
Weird... Yeah thats the thing i am also using a Core i7 930 CPU and my motherboard is ASUS ROG Rampage III Gene board, so i don't think my system is the problem here...
The wall charger delives 2 amperes to our HTC phones while usb ports delivery only 500mA (0,5 amperes). It's not only a matter of charging slower but you can't deliver the full charge the battery needs to revert the chemical process of discharging when tou use usb port. With 2amperes the charging process reachs it's maximum.
bravo261 said:
any usb not from china will give about 500mah, whether it be my i7 laptop or z550 vaio, so specific components shouldn't matter.
usb charges a little slower, but no reason it should not last as long once its got all the amps it can take. weird situation man...my huge list of htc phones never had an issue, and i do use a work computer to charge via usb sometimes
Click to expand...
Click to collapse
some cheap mainboards cannot supply even 500ma. a good qaulity board can supply more.
want to test it? put your HD2 in the first USB port and then put a high power device like a wireless dongle or external USB HDD in the second and see what happens. if your board cannot power both, you'll drop your wireless/hdd connection when you plug your phone in.
Phone Usage...
mbrown3460 said:
my phone hardly last one day..How do you make it last for 2 1/2 days?
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Click to collapse
Sir I have said that I am not a very heavy phone using guy, I am an average phone user. Plus I dont use the 3g or data connection here in my country since the connections are snail slow and prices are over the head and there is no unlimited data package here yet. I use the Wifi sometimes to update my twitter, Rss hub, facebook, weather tabs and very little market place... So my phone lasts for two and a half days when i use the wall charger.
Oh yeah and Guys, i tried recalibrating the battery by using it till the phone died completely and recharging it with USB (phone turned off) for like a day but still it drains faster than the wall charger rate.... I dont understand really...
Bicalho said:
The wall charger delives 2 amperes to our HTC phones while usb ports delivery only 500mA (0,5 amperes). It's not only a matter of charging slower but you can't deliver the full charge the battery needs to revert the chemical process of discharging when tou use usb port. With 2amperes the charging process reachs it's maximum.
Click to expand...
Click to collapse
This is why. The awnser was given, but people ignored it. To fully charge a battery it needs more amperes. Use the wall charger. The battery indicator lies, and is unable to acuratly measure a fully charged battery. It'll display 100% when it's roughly 70%.
Our batteries use Lithium ions as means of electricity. They use a Lithium compound, and move the ions from the negative to the positive pole. When there are no more ions to move, our batteries are discharged. When we connect to an external power source, the higher voltage will draw the ions back to the "negative pole".
USB supplies 500 mA (that's 0.5A) @ 5V (per specification, some motherboards won't be able to go that high, depending number of USB devices connected, etc)
European electrical sockets supply up to 2.5A @ 230V and although your HTC charger should only output 1A @ 5V, the topping off will occur much quicker.
Basically the more you have to charge, the more time it takes, and the bigger the effort on the current to pull the remaining ions back to the negative pole.
I am finding that in Android, my phone will not charge with either wall or usb charging. The phone shows that it is charging but does not actually charge. This is really unacceptable. It works in Windows Mobile but is not a listed problem of the Android builds. Are all of you using WM6.5 or Android? Or both?
jaylc said:
I am finding that in Android, my phone will not charge with either wall or usb charging. The phone shows that it is charging but does not actually charge. This is really unacceptable. It works in Windows Mobile but is not a listed problem of the Android builds. Are all of you using WM6.5 or Android? Or both?
Click to expand...
Click to collapse
I can Charge my HD2 well on both OS's but still when compared to android and WinMo when i use the USB Android does discharge heavily than WinMO and Android does the same when compared to WinMO on wall charger use as well... So nothing much more to say at that...
Charging mobiles using USB takes alot longer than using power outlet and this is valid for all kind of mobiles, ALSO when you charge by USB your mobiles battery drains much faster than charging from power outlet. (Electrical Engineers say so).
NOW why you don't use power outlet to charge your HD2 rather than using USB?
There are safety measures in charging from USB like, static issues from wall charger in some countries and then there is the ease of use from charging from PC while you are at work or away on a business trip..
mbrown3460 said:
my phone hardly last one day..How do you make it last for 2 1/2 days?
Click to expand...
Click to collapse
Mine lives for 5 days on just 1 charge, and with normal use (every 2/3 hours updating weather and twitter, sometimes call, sometimes texting, sometimes using internet)
I recently bought new tab, it is getting charged normally when plugged in power socket. But when i plug it in laptop USB port or any PC port, it would not charge instead I can transfer data etc. I am using the original USB cable which came in box. Does any one has faced same issue?
Sent from my GT-P1000 using XDA App
charging
Samsung have engineered it so you have to even use their mains charger. Car chargers and wall chargers have to be Samsung tab brand. Not sure but there is talk of AVUSB charge cable being released. Pretty sure this has already been covered.
Turn off the screen and wifi and data network and it will charge very slowly over usb.
Sent from my SGH-T849 using XDA App
The fact of the matter is the tablet requires more/not the right amount of power that your USB port can deliver.
We always here all these theories about why.. but here is the simple and only reason why.
To keep the techinical stuff short and simple, Li-Poly and other batteries have a predetermined lifetime and one of the determining factors to how long they last is the rate of charge (charge rate) time and the exact amount of mHa capacity of the battery.
This is NOT a Samsung marketing scheme as it is exactly the same reason the iPad cannot be charged through USB.
I'll give you a quick example:
If you buy rechargable batteries, Ni-Mh that state they can be charged at 2500mHa (capacity/rate) and you charge them on a 15 minute charger that delivers the right amount of power (1.2 volts) and not the correct rate (lets say they are rated for 2500 and you use a charger thats rated for more) this causes the battery life to be deminished drasitcally.
If you charge the same 2500mha batteries with a lower rating charger, they will take a lot longer to charge completely since it is at a slow mHa, but also this slower charging will provide a longer battery life.
Therefore their charger (and this is the reason why you must use their charger or any charger with the same mHa rating) is made to provide the optimal amount of charge rate (mHa) giving you the best battery life vs charge time.
In conclusion the Tabs hardware will limit the rate of charge through USB in order to:
a) Not overload the power on your USB, given that all this varies according to each system configuration (although it should not! but reality is.. it does)
and
b) In order to not improperly charge your tab, reducing your battery life.
I know the technical parts are vaguely/poorly explained but I work with Li-Po and other types so this is the simplest way to explain all this without causing too much confusion.
Hope this made sense
Cheers
tj1984 said:
Samsung have engineered it so you have to even use their mains charger. Car chargers and wall chargers have to be Samsung tab brand. Not sure but there is talk of AVUSB charge cable being released. Pretty sure this has already been covered.
Click to expand...
Click to collapse
Not true.
Samsung is using standard chargers that are wired to identify themselves as high current chargers. A non Samsung charger / external battery will likely have the same wiring because this wiring is part of the usb-specification.
The Tab will even charge from your usb-port but only slowly and if you turn off the screen since usb-ports only have 500mA (the charger has 2A).
So all the Tab does is check for this high-power-wiring. If it detects it it shows you the charge-icon, if it doesn't it assumes a usb-connection to your computer and does not pretend to charge (even if it does).
Interesting! So then a generic car cig lighter accessory with a standard USB port on it should charge it as a high output conection, right?
I am able to charge my Tab using usb connection to my PC by turning the device off. Same with an Energizer XP8000 external battery. Leaving the device on will take a long time to charge or not at all if you are using it while charging.
I just installed a QI charger for my new LG G2. I got a few QI charging pads as well. I want to see how fast it is charging, or the charge rate (500mah, 750? ect) as the receiver is supposed to do the following charge: DC 5V/500mA-1000mA .
Ive tried a few apps, but I cant find one that specifically says what the charging rate is. Anyone know the best way to figure that out?
Two questions:
1) When you say you "installed a QI charger for my new LG G2" exactly what do you mean there, and I do mean exactly: are you referring to getting a Qi charging pad (which you mention) or do you mean you got some kind of part that you physically installed in or on your G2 - the Verizon G2 is the only one that supports wireless charging out-of-the-box so, that's why I'm asking.
2) With respect to actual charging, the output of the Qi wireless charging pad is directly related to the amperage/current supplied by the actual AC adapter or USB charger you're using with it. If it's about 1A (the AC or USB charger) then you're going to lose quite a bit of power in the actual charging process because wireless charging is pretty severely inefficient most of the time, give or take you'd get 400 to 500mAh going into the actual device from the charging pad.
What I'm saying is if you have a Qi wireless charging pad, you'd be best served using as high an amperage/current charger for the pad itself so that the pad can then transfer as much as possible to the device itself. Anything less than a solid 2A charger attached to the Qi wireless charging pad and you're basically wasting a lot of it in the process and might be better off actually just using the USB port on a computer or something (about 500-550mAh max anyway).
Basic rule of thumb: the Qi wireless charging pad can use all the amperage/current it can get, with at least the factory LG 1.8A charger being what I'd call the bare minimum (and with that you'd probably be able to push about 900 to 1000 mAh (aka 1A) to the device. Qi hardware is roughly 40% efficient so, you're going to lose a lot in the process as stated; the more you start with the more that gets to the device even accounting for the inefficiency.
As far as measuring the current, you can try CurrentWidget on the Play Market, it may provide you with some info in terms of the charging rate.
br0adband said:
Two questions:
1) When you say you "installed a QI charger for my new LG G2" exactly what do you mean there, and I do mean exactly: are you referring to getting a Qi charging pad (which you mention) or do you mean you got some kind of part that you physically installed in or on your G2 - the Verizon G2 is the only one that supports wireless charging out-of-the-box so, that's why I'm asking.
2) With respect to actual charging, the output of the Qi wireless charging pad is directly related to the amperage/current supplied by the actual AC adapter or USB charger you're using with it. If it's about 1A (the AC or USB charger) then you're going to lose quite a bit of power in the actual charging process because wireless charging is pretty severely inefficient most of the time, give or take you'd get 400 to 500mAh going into the actual device from the charging pad.
What I'm saying is if you have a Qi wireless charging pad, you'd be best served using as high an amperage/current charger for the pad itself so that the pad can then transfer as much as possible to the device itself. Anything less than a solid 2A charger attached to the Qi wireless charging pad and you're basically wasting a lot of it in the process and might be better off actually just using the USB port on a computer or something (about 500-550mAh max anyway).
Basic rule of thumb: the Qi wireless charging pad can use all the amperage/current it can get, with at least the factory LG 1.8A charger being what I'd call the bare minimum (and with that you'd probably be able to push about 900 to 1000 mAh (aka 1A) to the device. Qi hardware is roughly 40% efficient so, you're going to lose a lot in the process as stated; the more you start with the more that gets to the device even accounting for the inefficiency.
As far as measuring the current, you can try CurrentWidget on the Play Market, it may provide you with some info in terms of the charging rate.
Click to expand...
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Firstly, thank you for taking time to write such a great response. I really appreciate it!
1) Yes I installed a universal sticker. I used this one http://www.amazon.com/gp/product/B00MN3RR7Q/ which is supposedly supposed to do 1000mA. People in the reviews seem to say they are getting good results. I wish the ATT version had wireless out of the box, but then if it did I would be stuck with PMA charging. I installed an actual NFC/PMA sticker in my G3. PMA kind of sucks...anywho.
2) This is the pad I am using: http://www.amazon.com/gp/product/B00H9B7ALK/. 1.5a input and 1a output. On this one, I am averaging about 3% per 10 minutes or 30% an hour. So roughly 3 hours and 20 minutes to full charge. I can try the the stock LG. Oh, my Dell Venue 8 Pro is a 2a one. I can try that as well. Can the paid take the 2a in even though it was built for 1.5a in?
I will try current widget. Ive been using battery monitor to log as well.
1) Neat, I didn't even know such a thing existed, I may have to give that a shot with my G2 at some point (if I decide to keep it, that is).
2) As stated before, using a higher amperage/current charger or power supply is preferred, sure. It should help get the charging done faster and again the device (meaning the charger) will pull what it requires and nothing more.
Basic electronics 101 here: two things that matter with respect to smartphone chargers (or most any device, to be honest) - amperage aka current and voltage.
Voltage is pushed from a power supply meaning it will always be the same amount, give or take micro-variations. If it's a 5VDC power supply (of any kind) it's designed to provide 5VDC constantly. If it's some other value, say 9VDC, 12VDC, and so on, that's how much it pushes - if you were to connect a 9VDC charger to a smartphone or other device that's designed for a 5VDC input, you'd fry the electrical circuits in the device because it would be flooded with more power than it's designed for.
Amperage aka current is pulled from a power supply and only what is required is what's actually taken. With respect to smartphones, most of the higher end devices these days can make use of roughly 1.2 to 1.8 A (read as Amps) when it comes to charging. This means if you had a charger that output 5VDC (from what I just said above that's the standard worldwide for such devices as smartphones) but could theoretically provide 5A of current, the smartphone technically would not be damaged because it would only pull roughly 1 to 1.8 Amps at most - if you do use CurrentWidget and you plug in the G2 and look at the reading while it's charging, you'll note that the level of amperage/current being pulled from the charger fluctuates like crazy - voltage stays constant (give or take a microvolt here and there) but the current will jump all over the place, especially if you enable the "Smart Charging" feature of the G2.
The reason this happens is because when a LiIon battery is pretty low on a charge, say down to 10-15%, it's "gone deep" as the saying goes and the charging circuit will pull the max amperage/current that the charger is capable of producing and that can be measured/seen using CurrentWidget. As the battery gets into the 90% full range, the amperage/current draw will reduce (again, especially with the Smart Charging enabled) as the battery gets towards being totally full. This is a good thing in most every respect and it keeps the LiIon battery in good shape too - if it pulled the max current till it was 100% it wouldn't necessarily be so good and would heat the battery up more than necessary and LiIon batteries are very sensitive to temperature variations.
Hence, phones get fried by "cheap Chinese chargers" a lot of times because of voltage issues and faulty voltage regulators, not from amperage/current problems. It's actually kind of difficult to kill a device with amperage/current, but screwing around with the voltage will destroy a device almost 100% of the time and quite fast too.
Also, this is the reason why you'll see a phone charge relatively quickly to the 99% point then it seems to take even longer to get that last 1% to finish it off at 100% - it's the way LiIon charging technology works and helps the battery lifespan (meaning how long the battery is useful for measured in years and not "battery life" in terms of how long it can run before you have to charge it again measured in hours). The charging process "slows down" as it gets close to being full which works great for this kind of technology.
Hope this info helps...
br0adband said:
Basic rule of thumb: the Qi wireless charging pad can use all the amperage/current it can get, with at least the factory LG 1.8A charger being what I'd call the bare minimum (and with that you'd probably be able to push about 900 to 1000 mAh (aka 1A) to the device. Qi hardware is roughly 40% efficient so, you're going to lose a lot in the process as stated; the more you start with the more that gets to the device even accounting for the inefficiency.
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Okay let me see if I understand this correctly. The OUTPUT of the qi charging pad could be 1000mAh, but since the wireless QI hardware is only 40% efficient, the actual charge rate will be more around mAh to 500mAh? Im recording an actual charge rate of 500mAh and my phone states it is on AC power and not USB.
If the receiver on the phone states it can do up to 1000mAh, what I need to find is a charger that outputs a lot more like 2000mAh and at 40% efficiency I might be able to get around the 1000mAh?
That pretty much sums it up, yep - as long as you account for the inefficiency of the Qi charging technology, you can get faster charge times and still use it without having to plug in/unplug, etc the old fashioned way.
It works, it's just not nearly as fast or efficient as the old fashioned way so, give the Qi pad plenty of current and you'll be fine - since it will pull what it needs, using a 1.8A or 2A or even more won't hurt it, but it will make it pretty damned warm to the touch when it's charging so keep that in mind. As the G2 would be sitting on top of the Qi pad, if the pad gets warm or even hot then obviously the G2 will as well by heat transfer and heat/high temps are bad for LiIon batteries as I mentioned earlier.
It's a trade-off more than anything else but again, it does work as long as you're understanding the hows and whys to make the best of it.
br0adband said:
That pretty much sums it up, yep - as long as you account for the inefficiency of the Qi charging technology, you can get faster charge times and still use it without having to plug in/unplug, etc the old fashioned way.
It works, it's just not nearly as fast or efficient as the old fashioned way so, give the Qi pad plenty of current and you'll be fine - since it will pull what it needs, using a 1.8A or 2A or even more won't hurt it, but it will make it pretty damned warm to the touch when it's charging so keep that in mind. As the G2 would be sitting on top of the Qi pad, if the pad gets warm or even hot then obviously the G2 will as well by heat transfer and heat/high temps are bad for LiIon batteries as I mentioned earlier.
It's a trade-off more than anything else but again, it does work as long as you're understanding the hows and whys to make the best of it.
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I ran the battery down to 70% and I have it on the charger with a 2a wall adapter. I will see how fast it charges. But it seems like I will get roughly 1/3rd the charging speed of a wall adapter. Which means in the car using gps with the screen on and QI chrarging will probably mean a negative overall power situation.
Im also going to try a high speed, charging only cable like this http://www.amazon.com/gp/product/B009W34X5O/ between the wall adapter and the charging pad to see if there is any difference.
Don't waste your money, that thing is no better than a "Gold Plated 56K Modem Cord," seriously. Gold plating, "high speed," all that stuff is marketing BS and means absolutely nothing in the long run - it's a microUSB cable, nothing more.
In 20+ years of using USB cords of all kinds I've yet to see one that's corroded so, that gold plating is not gonna matter anyway.
Any microUSB cable you can find today is more than capable of handling ~2A without a single issue and it's well known that the G2 can max out at 1.6A draw for charging anyway so any cable is more than adequate for doing it.
br0adband said:
Don't waste your money, that thing is no better than a "Gold Plated 56K Modem Cord," seriously. Gold plating, "high speed," all that stuff is marketing BS and means absolutely nothing in the long run - it's a microUSB cable, nothing more.
In 20+ years of using USB cords of all kinds I've yet to see one that's corroded so, that gold plating is not gonna matter anyway.
Any microUSB cable you can find today is more than capable of handling ~2A without a single issue and it's well known that the G2 can max out at 1.6A draw for charging anyway so any cable is more than adequate for doing it.
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Hah! I already have one I use in the car
shaxs said:
I ran the battery down to 70% and I have it on the charger with a 2a wall adapter. I will see how fast it charges. But it seems like I will get roughly 1/3rd the charging speed of a wall adapter. Which means in the car using gps with the screen on and QI chrarging will probably mean a negative overall power situation.
Im also going to try a high speed, charging only cable like this http://www.amazon.com/gp/product/B009W34X5O/ between the wall adapter and the charging pad to see if there is any difference.
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Okay I was able to maintain neutral power with the screen on and running gps. Let it go for almost 2 hours and it was at the same percentage as when I started. Im good with that for car use.
Hey, guys and gals.
Well, I found a Nexus 7 in my car the other day and can't figure out who it belongs to. All I know is that I can't boot it up and can't charge it. All I get is 5 blinking white lights. I don't know what it means but I did some research and it seems to mean that the tablet is too dead to boot up. However, it's not accepting any charge even though I charged it overnight. All I am getting is 5 blinking lights now......before I at least got the screen turning on with an empty battery being shown. (If that makes sense)
I am not using the original charger as I don't have one and am instead using my kindle charger. Could that make a difference?
Also, there seems to be some damage around the charging port area...However, the port itself seems to be in adequate condition.
Any ideas?
If it is taking a charge it should warm up a little when it is on the charger.
No warmth == no current going in.
If the battery is so old that it is nearly dead/shorted, the tablet will get HOT when it is on the charger.
So no warmth means no battery connection, either at the USB port or at the battery connector inside the device. There are threads on here from folks who had units where the internal battery connector wasn't seated well and came loose - the teardown to that spot to seat the connector isn't too bad... search for them.
On a 2A charger it takes ~ 3-4 hrs for a 5-100% charge for a N7. That happens initially at about 1500 mA, so it is possible that the voltage on your charger simply collapses if it is only designed for say 500 MA... if that were the case no charging could occur, or only pathologically small amounts of charging could occur.
Also, the N7 has a TI charge controller chip which needs *some* small amount of juice to operate, so it is unfortunately possible for the battery voltage to get so low that the chip can't operate correctly and you get a chicken-and-egg situation where the battery can't charge, even though it is healthy - the voltage just got so low that the charging chip doesn't work. In these cases, an external charger with current limiting is needed to partly charge the tablet battery to get the voltage up high enough so it can be reconnected to the tablet and charged normally. Note that this is a 3rd scenario where you wouldn't feel any "charging warmth" even though all the connections are good.
There is a report on here of someone doing something incredibly stupid - getting some charge onto the tablet battery by disconnecting the battery connector from the tablet and directly connecting it to a car battery to charge it (That's a recipe for a battery explosion or fire). Please don't do something like that.
Something a little less stupid would be using a power resistor (e.g. 5 Watt, 30 ohms) in series with the car battery to prevent too much current from flowing. That would be safe even if the tablet battery was a dead short ( 413 mA, 5.1 Watts in the resistor ), and if the tablet battery was healthy-ish, it would trickle charge at ~ (12.4-3.0)/30 = 313 mA with 3 W dissipated in the resistor.
The important point here is that wall-wart USB chargers are designed to produce 5V up to a certain current level, but they don't actually control the amount of current; that's the job of the funky chicken-and-egg TI charging chip in the N7. So you can't just hook a 5v supply directly to the tablet battery - as you have removed the current limiting control you need something to replace that function: either something dumb to limit the current (such as a power resistor), or a slightly more advanced charger that allows you to limit the current output to a moderate maximum rate.
Note also you don't need to fully charge the battery this way; you just need to bring the charge up a few percent so it can be reconnected to the tablet and charged the "ordinary" way.
good luck
bostonbeast225 said:
Well, I found a Nexus 7 in my car the other day and can't figure out who it belongs to.
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Really? [emoji15][emoji41][emoji56]
bluebirch said:
Really? [emoji15][emoji41][emoji56]
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OP could be a cab or uber driver or something like that
Did u ever get this sorted