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So I was wondering: is there a difference in charging speed between the a/c wall charger and charging from my computer's USB port? Also, what's the difference between different chargers? For example, the Desire comes with a charger that puts out 1 amp. My girlfriend's BlackBerry has a micro USB charger as well, but the output is 700 mAh, or 0.7 amp. I've seen chargers ranging from 500 mAh (0.5 amp) to 1200 mAh (1.2 amp). How does this equate to charge time? Does it even? Or does the phone regulate the charge rate?
Benny_L said:
So I was wondering: is there a difference in charging speed between the a/c wall charger and charging from my computer's USB port? Also, what's the difference between different chargers? For example, the Desire comes with a charger that puts out 1 amp. My girlfriend's BlackBerry has a micro USB charger as well, but the output is 700 mAh, or 0.7 amp. I've seen chargers ranging from 500 mAh (0.5 amp) to 1200 mAh (1.2 amp). How does this equate to charge time? Does it even? Or does the phone regulate the charge rate?
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You've pretty much answer your own question!
The current supplied by a charger/USB port determines how fast it can charge the battery, which is why the wall charger (1amp) charges much faster than a PC USB port (0.5 amps).
Regards,
Dave
It's almost completely logical.. say you have a 1.5A battery (1500mA) and a 500mAh charger (ie USB) then it will take 3 hours for it to charge but with a 1000mAh charger it will take an hour and a half.
Can't really explain it more than that, so hth.
Well , Yes and No
This is only partly true ......
If you charge it on the PC , max output is 0.5 amps , and data is possible while charging .
Now with Desktop and car charger , the amp can be anything the manufacturer likes but you have to keep the following in mind :
USB Specs state the following :
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In Battery Charging Specification,[32] new powering modes are added to the USB specification. A host or hub Charging Downstream Port can supply a maximum of 1.5 A when communicating at low-bandwidth or full-bandwidth, a maximum of 900 mA when communicating at high-bandwidth, and as much current as the connector will safely handle when no communication is taking place; USB 2.0 standard-A connectors are rated at 1500 mA by default. A Dedicated Charging Port can supply a maximum of 1.8 A of current at 5.25 V. A portable device can draw up to 1.8 A from a Dedicated Charging Port. The Dedicated Charging Port shorts the D+ and D- pins with a resistance of at most 200Ω. The short disables data transfer, but allows devices to detect the Dedicated Charging Port and allows very simple, high current chargers to be manufactured. The increased current (faster, 9 W charging) will occur once both the host/hub and devices support the new charging specification.
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So if your Desire ( Yes , the Desire supports these specs ) detects the short , it will switch to fast charging mode otherwise it will limit the charging current .
Unfortunately , there's no way to know , just by looking at a charger, if it respects the specs or is just a low cost 5V powersupply . I've encountered quite a few ( mostly lowcost) desktop and car chargers that are rated between 1 and 2 amps , but still take bl**dy ages to charge the phone . Checking those with a measuring tool , you usually see the data pins are "Not Connected" instead of being shortened :-(((
Final Word .... don't try to save some money on a cheap charger , you'll regret it Genuine HTC works great , others do the same , but don't expect a $1 charger from Hongkong or whereever to do it !
These are the theoretical specs. Keep an eye on charger efficiency ratings and battery charge absorption won't be 100% in any case. Also bare in mind the charge is not linear, it will trickle after approx 80-90% with this phone.
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- Sent via my HTC Desire -
th3 said:
These are the theoretical specs. Keep an eye on charger efficiency ratings and battery charge absorption won't be 100% in any case. Also bare in mind the charge is not linear, it will trickle after approx 80-90% with this phone.
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- Sent via my HTC Desire -
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Ya, I noticed the charge slows down considerably for the final 10-15 %
I find myself charging my Desire more than I actually use it, lol.
I found now the answer to this problem: I use a Nokia charger (5v and 890 mA) with a microusb adapter. You can find one on eBay at ~2$
Now it takes about 2 hours from 20% to 100%
Lets hope nothing wrong happens to my precious Desire
look here for a method to charge at ac speed from usb, explains a few things too.
Is this the highest?
http://www.seidioonline.com/product-p/pmc.htm
Post links if you know of higher ones, thank you.
Sent from my ADR6400L using XDA App
There are 2.1A usb adapters, but I don't think microUSB can take advantage of it. The one you linked is a 1A, which is the same as the wall charger HTC gave with the phone. I'm currently using a 1A usb adapter in my truck.
Ok that's probably what I'm looking for then. Are there wall chargers greater than what came with the phone that I can take advantage of?
Your best bet would be to try the USB adapters made for iPads. The Apple products can utilize the 2.1A chargers with their sync cables, but I'm not sure if a microUSB cable can though. I have some 2.1A wallchargers from some of my Apple products, I'll test them later and let you know what I find out.
http://www.verizonwireless.com/b2c/...ryDetails&archetypeId=12299&accessoryId=46370
I just got an Enercell from Radio Shack with dual usbs. Max output is 2.5A divided between the two ports.
http://www.radioshack.com/product/index.jsp?productId=11329448
on sale now for only $14.99. Seems to be of good quality.
The Motorola rapid chargers rock.
Guys, unless you mod the usb adapter 5V spec, you aren't doing squat with a "high power" adapter. The device has an input impedence that will draw a certain amount of current at 5v., and that's it.
Standard battery: 1400 mAh
Time to charge: 4 hrs (according to manual)
That's 1400/4 = 350 mA.
Most adapters on the market spec more than that, they're usually 500 mA or above. And again, unless you boost the volts, you're not going to be able to push more than 350 mA or so.
So don't waste you're money.
On the other hand, if your going to share a car outlet with another device like mp3 or ipod, then yeah, you'll need a higher output, two port, adapter.
Edit: It just occurred to me that if you're using the phone heavily while charging, then yeah you may need more than 500 mA. My currrent widget shows the phone can draw another 250 mA or so during use. That plus the charge totals to around 600 mA. But depending upon design, the phone may not be able to pull in all 600 mA. A test with a current meter would be real interesting.
The charger shipped with the Thunderbolt is a 1 Amp charger.
If I use a 500 mA charger the Current Widget shows a +450mA charge current. However if I use the 1A charger, I get a charge current of about +850mA.
Given that the google navigation gobbles over 400mA when running, you need a car charger with greater than 500mA capacity of you want the phone to charge at the same time.
Sent from my ADR6400L using XDA App
boingboingbilly said:
The Motorola rapid chargers rock.
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Good to hear, I ordered one today for $11 on ebay. I had heard other people say they liked that one too.
Ecomaniac said:
Guys, unless you mod the usb adapter 5V spec, you aren't doing squat with a "high power" adapter. The device has an input impedence that will draw a certain amount of current at 5v., and that's it.
Standard battery: 1400 mAh
Time to charge: 4 hrs (according to manual)
That's 1400/4 = 350 mA.
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You're making the incorrect assumptions that the charging rate is constant, and charging is 100% efficient. Li-ion batteries can be charged at up to a 1C rate (i.e. 1.4A for a 1400 mA cell). Add the power drawn by the phone itself, and a 1.8 Amp charger might not be unreasonable (1.8 A is the specified limit for micro USB connectors). Whether the phone will actually do a maximum rate charge, I don't know.
This, from a TI Application Note (Google for SLAA287, board won't let me post links):
A Li-Ion battery charging process consists of three stages:
· Slow Charge: Pre-charging stage using current of 0.1C
· Fast Charge: Constant current charging stage using current of 1C
· Constant voltage charging stage
During the slow charge stage, the battery is charged with a constant low charge current of 0.1C, if the battery voltage is below 2.5V. The slow charge stage is rarely used during the charging process of a Li-Ion battery.
The fast charge (constant current) and constant voltage charging are the most important stages during a recharge process. Most Li-Ion batteries have a fully charged voltage of 4.1 or 4.2V.
The battery is first charged with a constant current of 1C until a battery voltage reaches 4.1 or 4.2V. The firmware continuously checks the charging current by sensing the voltage at the current sense resistor (Rsense) and
adjusts the duty cycle of PWM output from the MCU. The battery's voltage is checked frequently.
Whenever found the battery's voltage reaches 4.1 or 4.2V, the charger will switch to constant voltage charging mode. The battery is then charged with a constant voltage source at a fixed battery voltage of 4.1 or 4.2 V...When the charging current falls below 0.1C, the charging process must stop.
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Monoprice has Cig to USB(1A) chargers and the USB to Micro cables in multiple lengths(I ordered 6' ones) for far cheaper than you will find anywhere else
mike.s said:
You're making the incorrect assumptions that the charging rate is constant, and charging is 100% efficient. Li-ion batteries can be charged at up to a 1C rate (i.e. 1.4A for a 1400 mA cell). Add the power drawn by the phone itself, and a 1.8 Amp charger might not be unreasonable (1.8 A is the specified limit for micro USB connectors). Whether the phone will actually do a maximum rate charge, I don't know.
This, from a TI Application Note (Google for SLAA287, board won't let me post links):
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very useful, thanks!
walbuls said:
Monoprice has Cig to USB(1A) chargers and the USB to Micro cables in multiple lengths(I ordered 6' ones) for far cheaper than you will find anywhere else
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I second monoprice.
I tried bunch of cig to usb car charger and none matched advertised output... They all showed Charging (USB). I now use AC inverter and it charges just like a wall charger.
eccenpix said:
I tried bunch of cig to usb car charger and none matched advertised output... They all showed Charging (USB). I now use AC inverter and it charges just like a wall charger.
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I suspect you need to find one which properly follows the USB Battery Charging Specification. That link is to the most recent version, which came out on 7Dec2010 (remember Pearl Harbor!). Version 1.1 is easier - a Dedicated Charging Port is indicated by shorting together the data lines (the two middle conductors on a full sized USB connector. By doing so, it indicates the device may try to draw up to 1.8 A of current (although a dedicated charging port is allowed to limit the current to less than that, it must provide at least 1.5 A).
I bought a cheap USB hub with 5 ports, used an exacto knife to cut the traces going to the data lines (the middle two) on all the ports, and then shorted them together on each port. It's now no longer a USB hub, but a USB charger with 5 ports I can used to charge stuff (phone and Bluetooth, quite often). The AC adapter which it came with does 2 Amps. My Thunderbolt says "Charging (AC)" when plugged into it.
So, if you can open up one of your adapters, just solder a jumper between the middle two contacts (make sure they're not connected to anything else).
Just got the Rocketfish premium microUSB at Best Buy and it has a captive coiled cord and a USB port. TBolt says "AC plugged" and reads +670 mA.
Good choice on the Motorola Rapid Charge - I've burned through 3 other cheap car chargers trying to keep my phone alive while using Google Nav and this is the first one to work!
i have the rapid motorola one on amazon
lippstuh said:
i have the rapid motorola one on amazon
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+1 Works great! Battery widget usually shows about +800mA while only charging. Real close to the wall charger
I bought an OEM Samsung wall charger that charges at 1 Ampere. I started to charge my Zerolemon battery with it yesterday at about 6pm and here it is today and it is only at about 80% charge rate. Something is not right. I contacted the seller and they told me that the charger is from Samsung and it charges at 1 Ampere. It is either the charger is a knock off or my Micro-usb cable that connects into the wall charger is not the right kind.
Are there different variations of micro-usb cables that will work better? Some that allow more current to flow over them than others? My cable says that it is 28awg/2C. I remember when I had a playstation 3 I had problems with syncing the device with my playstation 3 with the USB cables I had bought. After tons of research it was the USB cables that were the issue. They didn't allow enough current to work properly with the PS3. I'm starting to wonder if I'm having the same issue with the Samsung Wall Charger. Is the 28awg wire gauge too thin?
---->[email protected]<---- said:
I bought an OEM Samsung wall charger that charges at 1 Ampere. I started to charge my Zerolemon battery with it yesterday at about 6pm and here it is today and it is only at about 80% charge rate. Something is not right. I contacted the seller and they told me that the charger is from Samsung and it charges at 1 Ampere. It is either the charger is a knock off or my Micro-usb cable that connects into the wall charger is not the right kind.
Are there different variations of micro-usb cables that will work better? Some that allow more current to flow over them than others? My cable says that it is 28awg/2C. I remember when I had a playstation 3 I had problems with syncing the device with my playstation 3 with the USB cables I had bought. After tons of research it was the USB cables that were the issue. They didn't allow enough current to work properly with the PS3. I'm starting to wonder if I'm having the same issue with the Samsung Wall Charger. Is the 28awg wire gauge too thin?
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- charger is rated 1amp but usually puts out less depending on the quality and efficiency of it. You won't get the fastest charge with a 1amp psu. Get yourself a cheap 2amp and have plenty of headroom.
- also, if voltage in your wall outlet is low (rare) that would affect psu output.
- yes super thin usb cables can be part of the cause.
- of course, if the cable is meant for PC charging, it will be wired in such a way, to not exceed 450ma (or so) whereas a usb cable or charger that is meant and wired for fast charge, will provide...for me...1150ma (Search/Research my past posts for more detailed info)
- also, most kernels, slow down the charge rate as the batter gets closer to 100% charge.
- a bad battery or custom kernel with bad code, could both affect charging speed.
I have recently bought an Oukitel K6000 Plus.
I also own an HTC One M8, several chargers, and several USB meters.
The HTC One M8 was sold with a classic 5V 1.5A charger, but the phone by itself has a QC2 chip, and can accept 9V chargers (QC2). When you put a USB meter between a QC2 charger and the M8, you see that after 5s, the charger goes for 9V.
With very recent phones, and QC3, you should see 12V.
QC3 protocol is designed to never burn an uncompatible phone; but, take care about your USB meter, some USB meters may not accept above 7V. I have various USB meters, some take 7V, some 9V, some 13V, some 20V. The protocol is harmless for active devices; but since the USB meters is a spy, it may burn if not designed for high voltage.
On my desk, I have set-up a classic 9V PSU with a USB plug; this way, my phone does not negocate; and I have put a thick copper cable, to have no loss. My HTC M8 was happy with this; the QC2 chip can accept direct 9V. All other devices would burn on this plug, because on this plug, I send raw 9V without any protocol or negociation. This is home made.
Note that older HTC phones like the Sensation do not implement yet Quick Charge (Sensation is not even QC1), and still it accepts up to 7V (it's written in some file under /sys). So, while most people used to use 5V USB chargers for the Sensation, I have already built my fixed 7V charger for this phone ... and i was charging twice faster than any one else; and I was probably the only person on the planet to charge the Sensation at 7V.
Now, I own two 9V phones, and two official 9V chargers. When I plug the K6000 on the provided charger, USB meter nicely adverts 10V. When I plug my M8 on a QC2 charger (from Amazon), USB meter also shows a nice 9V. This means super fast charge (90-100 min to fully charge from 0% to 100%; at most 120mn if I am using the phone during charge).
The issue I had was when I tried to swap the chargers: put the M8 on the Oukitel charger, and the K6000 on a QC2 charger. Then, in both cases, the USB meter sticks to 5V.
This means ... neither the Oukitel charger, or K6000 phone are QC2 compatible. Oukitel does a fast charge, at 9/12V; but not with the Quick Charge protocol.
This means, if you buy any faster charger from anywhere, the Oukitel phones will charge at only 5V; and when you count on voltage loss over the USB cable, I sware you will be luck if you charge your phone in 4h, phone switched off.
After spending a few hours on Google, I have those three sellers, who sell the original Oukitel charger:
https://fr.aliexpress.com/item/Orig...51960957.html?spm=a2g0w.search0304.4.9.Si9JZR
https://fr.aliexpress.com/item/Ouki...730221.html?spm=a2g0w.search0302.4.142.rUQMcL
https://fr.aliexpress.com/item/Orig...129853.html?spm=a2g0w.search0302.4.180.ZOEQRv
Out of this, I have been completely unable to find any 9/12V charger for Oukitel on any other website: Ebay, Amazon, BangGood ...
This becomes a huge issue for car chargers: since absolutely no-one builds "Oukitel compatible" chargers, and Oukitel does not seem to build any car chargers ... there is no car charger for the Oukitel.
The workaround is to buy a 9V car supply, and solder a USB cable on it. Most Oukitel phones take 9V (K6000 pro and plus; several K4000). IMHO, the K10000 takes 12V (but, you should check this yourself).
Even if the K10000 accepts 12V, you can not provide the raw 12V from the car, because the car voltage may vary from 11.4 to 15V (strictly, all car devices must be 18V compliant; truck devices must be 36V compliant). Your phone may dislike the 15V peaks (which occur frequently).
I am not yet sure about the exact voltage my K6000 Plus wants. My USB meter shows 10.4V, on PSU side. I don't know if this ought to be a very low 12V because PSU has a poor design, or if the Oukitel protocol includes a fine tuning communication, so that the phone receives 9V on phone plug, and PSU has to over-voltage the output voltage to compensate the loss over cable. When USB meter says there are 10.4V on USB-A plug, the phone claims 9.2V on phone side. Not sure the reason of this. More testing would need a few hours digging (insert the USB meter at the micro-USB-B side).
So, can any one give any detail on the Oukitel protocol used for charger voltage tuning ?
When I plug my Oukitel on the raw 9V USB plug, if Android is running, the phone is happy, and will charge the battery. If the phone is turned off, then, the phone will refuse to charge from 9V (you either need a 5V charger, or start Android - have not tried to dig what happens with TWRP, Recovery, FastBoot, FactoryTools ...).
I am very sad to see this phone completely uncompatible with classic protocols. I understand that the license for QC2 chip is very expensive, and the Oukitel phones are designed to bring huge power at low cost; they walked around the QC2 patents by redesigning the Faster Charger; I can understand this from a dev point of view; but I completely reject it from a user point of view. All my QC2 chargers are useless; and without the original Oukitel charger, charge time has to be 4-8h, with phone iddle or off.
Unless you solder a USB plug on a 9V PSU ... which is very dangerous if you accidently plug an uncompatible device (earset, power bank, old phone ...).
And, don't just take any 9V PSU; it needs to be able to feed at least 1.5A !!!
I feel disapointed.
Quick Charge just came out with a good standard, and more and more phone brands were starting to use it (Samsung, Nokia); and chinese companies now re-invent the wheel ... this brings me back to the old times of Mac being uncompatible with Windows ... when saving a word document on a floppy was the most complicated thing on earth because you had to take care about bitwise issues (a file written on a floppy with Microsoft-Word from a MAC could not be read with Microsoft-Word on Windows-PC ... then, after a few years, they published an update to fix the issue )
Hey!
I noticed recently that my G5 charges quite slow. So I tested all of my powerbanks, cables, and wall chargers, in various combinations. I had 4 different powerbanks, 3 wall chargers, and 4 cables.
I used a USB ammeter to measure the power draw going through the USB cable.
On the motorola charger and cable that came with the phone, it charges at 1.8a. I then charged my phone from each powerbank and wall charger, using each cable in turn. The average charge speed for my phone was about 0.5a. Out of 28 combinations, only 2 yielded a draw over 1a.
I have created a spreadsheet detailing the charge speeds of each combination, but unfortunately cannot post it yet (10 post permissions).
I then charged my USB powerbanks from the same wall chargers, using the same cables. One powerbank charged at over 1a with every combination, and reached over 2a on numerous combinations. This proves that the cables and wall chargers are not at fault, it is a phone issue.
Why? Has motorola put something in their chargers that 'talks' to the phone, and allows for faster charge speeds? 0.5a is awful!
Secondly, does anyone know of cables that I can buy, which will support fast charging for the motorola? I have looked at genuine motorola cables, but there is no way to tell one from the other.
Thanks!
Paul
P.s. charge speeds were the same, whether the phone was switched on or off.
Welcome @agour
I've come up to a similar conclusion with a lot less data (thus I didn't share them).
I caught power consumption at the wall outlet when charging my device with two chargers: Motorola stock charger and a Samsung Adaptive Fast Charger.
The Samsung has the following specs: 5V 2A or 9V 1.67A with fastcharging capable device.
Using Samsung Adaptive fast charger and Samsung 1.5m cable : 6W, so the device charges at something like 5V 1.2A...
Using Samsung Adaptive fast charger and the cable provided with my XT1676 : 11.3W (which is coherent with the max 9V 1.6A, and would mean the charger provides 2.2A if at 5V which more than the specs.)
Using stock charger and stock supplied cable : 11.3W ==> fast charge for similar reasons as above
Using stock charger and Samsung 1.5m cable : around 6W ==> low power charge
I'd need a USB multimeter to confirm those data. (mostly due to the variable voltage that can provide fast charge adatpers)
matmutant said:
Welcome @agour
I've come up to a similar conclusion with a lot less data (thus I didn't share them).
I caught power consumption at the wall outlet when charging my device with two chargers: Motorola stock charger and a Samsung Adaptive Fast Charger.
The Samsung has the following specs: 5V 2A or 9V 1.67A with fastcharging capable device.
Using Samsung Adaptive fast charger and Samsung 1.5m cable : 6W, so the device charges at something like 5V 1.2A...
Using Samsung Adaptive fast charger and the cable provided with my XT1676 : 11.3W (which is coherent with the max 9V 1.6A, and would mean the charger provides 2.2A if at 5V which more than the specs.)
Using stock charger and stock supplied cable : 11.3W ==> fast charge for similar reasons as above
Using stock charger and Samsung 1.5m cable : around 6W ==> low power charge
I'd need a USB multimeter to confirm those data. (mostly due to the variable voltage that can provide fast charge adatpers)
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Interesting! It's suprising how much difference the combinations can make.
I don't think I have experienced this on a phone before, however I have never felt the need to test it...
I tested the original cable that came with the phone, and an off the shelf 'genuine motorola cable'. The stock cable is still the fastest, however the secondary cable still worked very well.
Interestingly, one of my powerbanks will charge at 2.2a from pretty much EVERY powersource and cable combination. This is with 7 cables tested, and 3 USB wall adapters.
Shame that motorola doesn't allow their phones to draw maximum power from hardware that can provide it..
agour said:
Interesting! It's suprising how much difference the combinations can make.
I don't think I have experienced this on a phone before, however I have never felt the need to test it...
I tested the original cable that came with the phone, and an off the shelf 'genuine motorola cable'. The stock cable is still the fastest, however the secondary cable still worked very well.
Interestingly, one of my powerbanks will charge at 2.2a from pretty much EVERY powersource and cable combination. This is with 7 cables tested, and 3 USB wall adapters.
Shame that motorola doesn't allow their phones to draw maximum power from hardware that can provide it..
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If I have some time, I may test internal impedance of the cables, it is possible that the device somehow probes the cable (or the cable + charger) and then decides if it can or not draw that much power without overheating/melting the cable; and then it will negotiate the quickCharge with the charger.
there has been a discussion about quick charge on this thread a while ago (before I got this devices : https://forum.xda-developers.com/g5/help/quick-charge-3-0-support-t3632457)
Lenovo adds the following that I have not tested:
Lenovo said:
If your device is below 78%, but it does not begin Turbo charging when you plug it into the Turbo Charger, try uplugging and plugging back in using one fluid motion.
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[Source]
It is quite obvious that especially cheap cables will charge phones much slower as the resistance is too high, even if the phone does not perform any checks. Those cables are basically too thin. Resistance limits the current (amps) that can flow. Newer phones most likely just look at the charge current during the first x seconds (or less) and then decide wether to enable fast charging or not to keep the cable from heating up. A wire with high resistance is basically a heater. So it's a necessary safety feature (from the companies POV).
Regarding the power bank, it may be possible that this particular design provides a voltage slightly higher than the nominal 5 volts (still fine for most devices), which helps overcome the resistance. That is also the reason why the Samsung fast charger provides 9V: You don't need a cable as thick as with 5V.
Keep in mind that the USB specifications only recently got updated for such high charging currents, so it is advisable to use only the cable that comes with the phone as USB cables in general don't need to provide such high currents by spec!
71n4 said:
It is quite obvious that especially cheap cables will charge phones much slower as the resistance is too high, even if the phone does not perform any checks. Those cables are basically too thin.
Resistance limits the current (amps) that can flow. Newer phones most likely just look at the charge current during the first x seconds (or less) and then decide wether to enable fast charging or not to keep the cable from heating up. A wire with high resistance is basically a heater. So it's a necessary safety feature (from the companies POV).
Regarding the power bank, it may be possible that this particular design provides a voltage slightly higher than the nominal 5 volts (still fine for most devices), which helps overcome the resistance. That is also the reason why the Samsung fast charger provides 9V: You don't need a cable as thick as with 5V.
Keep in mind that the USB specifications only recently got updated for such high charging currents, so it is advisable to use only the cable that comes with the phone as USB cables in general don't need to provide such high currents by spec!
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That sounds correct, although my Samsung wall adapter is fast charge capable, and was provided with a cable (and not a cheap one), that basically can't be use for fast charging with the G5, that looks silly...