I was always wondering how to speed up this unacceptably slow USB charging (If you are in a low signal area with bluetooth ON then the battery is drained far more quicker than the laptop can charge it ending up with a flat battery ). Finally I tested the output from the pins of the wall charger and my Laptop. Even when the laptop is powered off (no data exchange) the USB charging is very slow. The HD seems to send a ~1v pulse through D+ channel when to connect it to USB port (even when powered off the device seems to check if it is a USB data port), but with the charger it does not!, so we need to break this communication.
So I put a thin plastic film over the D+ and D- terminals of the USB cable and voila the device charges much faster..(slightly slower than wall charger - 25% slower, can be accounted for by the lower power output of the laptop USB port, the voltage of laptop usb port is 150-200 mV lower).
While I am typing this my HD has gained 9% charge with screen on!! . Natively it charged atmost 1% by this time with screen off.
Now I am looking for a permanent mod for my spare USB cable hacking off the data lines.
For those in a hurry with nothing but a HD with flat battery USB cable and a computer at hand, worthwhile using a thin paper over the inner two pins of the USB cable on PC side and plugging it in. (You do this at your own risk).
Hope it helps others too. Let me know your experiences.
With my Desktop USB port, charge rate is better than wall charger if you block the data pins. The port seems to be capable of 1.5 amp at 4.96 v
Also ensure that the USB cable snugly fits the mini USB port on HD.
Could this be also the problem why (my) Blackstone doesn't receive a TMC-signal with HyperGPS & iGO8 while charging in my car?
It's a genuine car charger from HTC, so I should say these pins are already "shut" from connection, or am I wrong?
I have a usb cable that is dedicatet for charging. It dosent have D+/- wires. With this cable on my laptop the charge time form about 20% is more than half of regular USD cable..
The cable was supplied with a car BT handsfree.
Regarding the TMC issue Im not shure, Try asking the guys that developed HyperGPS they might know, if not they might be able to fix if they arent aware of the issue
Interesting tip, thanks... I've lost my charger and have been finding it a pain to charge it using the USB port on my laptop.
I cut a small strip of paper from one end of a sticky note, and stuck the adhesive end to the outer flat surface of the USB plug to secure the strip in place. Seems to have done the trick, because the charging light is on and the PC hasn't detected the device. As for how long it takes to charge... will have to wait and see.
Also, I was wondering if there was any difference in charging speed (i.e. when charging via USB normally without using this trick) between activesync and file transfer mode?
Related
I recently bought a custom 2 amp charger after the stock one died. Anyways, whenever I plug it in, I noticed that it would ask me whether I wanted to access the USB storage. Apps that need the SD card similarly, would terminate (ex: music).
Is there any way to solve this and to make the phone realize that this is a power outlet charger and not a USB charger? I think that the Epic drew about 650 milliamps or so charging and much smaller over PC (I think about 350 to 400 ish IIRC). It seems to currently only be charging at PC USB speeds as well and not the same rate as the stock charger.
Thanks in advance.
There's a way for the phone to tell if it's connected to a PC or AC adapter depending on a resistor shorting out two pins. Make sure you don't have anything other than the +5V and Ground connected.
I had the same thing happen with a car charger. Bridging / shorting the data pins causes the Epic to see the charger as a regular charger, and not usb for data or charging. This can also be done in the cable, itself, however, then you have the problem of having to cut part of your USB cable and re-tape or heat-shrink tube it.
There's a couple threads discussing similar problems/solutions:
http://forum.xda-developers.com/showthread.php?t=908363
http://forum.xda-developers.com/showthread.php?t=709226
Ok I recently found my TF101 losing the quick charge capabilities, so I went on and on to find the rootcause, the charging cable at the end of the tablet has some tiny broken piece at the round plastic part and it's no way to defect the cable..
Another issue, my 15month son once time chewed the charging cable over the proprietary connector side while the plugged in the wall (no harm since it is 5v, 2.1A), it was wet but hair dryer did the job
After that I plugged the charging cable to the ac adapter, tablet...but now the thunderbolt charging icon won't show up but charging very very slow (called trickle charge) - 12hr for 100%...
Lucky for me, my co-worker uses TF101 too, so I borrowed his ac and charging cable to test...FINALLY, it was the charging cable
So everyone else,,, I guess if you suspect your AC Adapter fried or something, just try to charge your phone, if it works, it works - the charging cable can be defected and degraded so it will charge fast or slow depending the CHARGING CABLE as well - it's ironically found but I now had to believe CHARGING CABLE is also another factor in this equation rather only AC Adapter itself!
good luck!
rcjpth said:
So everyone else,,, I guess if you suspect your AC Adapter fried or something, just try to charge your phone, if it works, it works - the charging cable can be defected and degraded so it will charge fast or slow depending the CHARGING CABLE as well - it's ironically found but I now had to believe CHARGING CABLE is also another factor in this equation rather only AC Adapter itself!
Click to expand...
Click to collapse
I wouldn't recommend plugging in any other usb rechargeable device into the Asus AC adapter because it outputs 10V if I remember correctly.
Unless you KNOW the device you are plugging in can handle the output voltage from the ac adapter, DO NOT PLUG IT IN because you run the risk of frying your device.
Spd2Last said:
I wouldn't recommend plugging in any other usb rechargeable device into the Asus AC adapter because it outputs 10V if I remember correctly.
Unless you KNOW the device you are plugging in can handle the output voltage from the ac adapter, DO NOT PLUG IT IN because you run the risk of frying your device.
Click to expand...
Click to collapse
It uses a USB3 pin to detect the TF, and ups it to 15v at 1.2a. Unless it can detect the TF USB3 pin, it only outputs 5v at 1.x or 2.x amps (I forget the exact number).
I had JUST finished reading about that in some other thread and was coming here to correct myself. You beat me to it by a few minutes.
rcjpth said:
Ok I recently found my TF101 losing the quick charge capabilities, so I went on and on to find the rootcause, the charging cable at the end of the tablet has some tiny broken piece at the round plastic part and it's no way to defect the cable..
Another issue, my 15month son once time chewed the charging cable over the proprietary connector side while the plugged in the wall (no harm since it is 5v, 2.1A), it was wet but hair dryer did the job
After that I plugged the charging cable to the ac adapter, tablet...but now the thunderbolt charging icon won't show up but charging very very slow (called trickle charge) - 12hr for 100%...
Lucky for me, my co-worker uses TF101 too, so I borrowed his ac and charging cable to test...FINALLY, it was the charging cable
So everyone else,,, I guess if you suspect your AC Adapter fried or something, just try to charge your phone, if it works, it works - the charging cable can be defected and degraded so it will charge fast or slow depending the CHARGING CABLE as well - it's ironically found but I now had to believe CHARGING CABLE is also another factor in this equation rather only AC Adapter itself!
good luck!
Click to expand...
Click to collapse
I'm glad you found your problem. So should we disregard your last 4 posts of Asus conspiracy and faulty TF and Dock FW updates?
No mann - I believe they already planted the conspiracy around us - see we are all in purchasing the TF101 - now we need to spend more money for the accessories ...etc - you see how they lure us into this kind of sh(*&()&)(*&
rcjpth said:
Another issue, my 15month son once time chewed the charging cable over the proprietary connector side while the plugged in the wall (no harm since it is 5v, 2.1A), it was wet but hair dryer did the job
Click to expand...
Click to collapse
You let your 15 month old son crawl around unshielded power sockets and plugged-in power cables with little enough supervision that you couldn't stop him before he was already chewing on it?????
Hello
I'm hoping some USB expert can help me out here, I'm trying to make a USB to DC (2.5mm plug) cable that can supply 2A, I have the popular HP Touchpad wallcharger that's rated 5v 2A , so I took a spare quality usb cable (copper cables) it has red, black, green, white (and a big bare metal cable and aluminum wrapping, shielding probably), the DC plug end has two wires red + black, so I hook up red to red black to black (red is 5V black is ground, tested using a multimeter) but I don't seem to be getting as good of results that the stock cable I have gets, the stock cable charges the device at around 1.8 Amps , the cable I made only outputs 800ma to 1.3 amps and if I turn the brightness up it stops charging like it can't supply enough power amps (again stock cable works fine with full brightness).
I'm wondering if on the charger end I need to do something with the green, white wires they both output around 2 volts should these be shorted to the black or possibly red wires to add additional amperage?
I found a youtube video where someone made a similar PSP charger and they spliced both the green, white and blacks wires together, I just want to make sure this is correct way to do things.
youtube.com/watch?v=8WhMeZkrK8U
Btw I also purchased a pre-made cable from dealsextreme but it exhibits the same behavior where full-brightness the charging light dims and goes out on my device, I assumed the low quality of the cable was to blame or again something needs to be connected with the green, white wires.
I know similar questions have been asked before but most have dealt with USB to USB fast charging , with USB to DC I'm confused on what to do with the D- and D+ wires at the charger end should they be shorted together? or to the black cable
ok I think I answered my own question, I tried to do a Ohm test on the stock cable and it seems there was no connection to the green and white or to any of the other wires, since the Ohm reading always returned 0, red and black got a 1+ reading meaning they were connected and a circuit was completed.
Looking at my stock cable it has a big black magnet on it, researching google i found this might be a ferrite core cable, so maybe this somehow boosts the signal and lets the cable pull more amperage or something.
The cylindrical lump on some cables is a ferrite core.
Its purpose is to reduce the amount of logic-generated RF noise from finding its way onto the main span of cable and using it as an antenna.
It will not affect any aspect of charging/powering a device.
Yes, the white/green data pair are used sometimes to indicate a dedicated charger.
A dedicated charger can have more current drawn from it than a normal USB connection.
This subject is handled exhaustively here: http://forum.xda-developers.com/showthread.php?t=1384253
otyg said:
ok I think I answered my own question, I tried to do a Ohm test on the stock cable and it seems there was no connection to the green and white or to any of the other wires, since the Ohm reading always returned 0, red and black got a 1+ reading meaning they were connected and a circuit was completed.
Looking at my stock cable it has a big black magnet on it, researching google i found this might be a ferrite core cable, so maybe this somehow boosts the signal and lets the cable pull more amperage or something.
Click to expand...
Click to collapse
What are you trying to do, make another Touchpad charger? I assume you made sure it can supply up to 2A at 5V.
Many chargers including the HP Touchpad one IIRC short the green and white data wires and this tells the device it can draw more current. If your ohmmeter was reading 0 then that would mean they are shorted. I don't think they are tied to ground (black) just to each other.
The ferrite choke is there to suppress noise from the switching transformer so the device gets clean DC power when charging.
Thanks,
I was trying to make a cable for a Chinese tablet that cannot be charged through it's USB port and only has a 2.5mm dc power port, it seems to be pretty picky about the cable being used, so far the Stock cable to USB-DC to wall USB charger works fine (hp touchpad charger), and a true DC brick rated 2000ma , 5v to DC port works good, I wanted an extra cable to use to charge it with my HP usb charger so I ordered this from dx.com
http://dx.com/p/usb-to-2-5mm-dc-charging-cable-2538
as always I check the polarity and voltage of the cable and it showed 5.13 volts, and center pin positive, strangely when I hooked it to the tablet I saw the battery charging , at 100% I turned brightness up and ran a 3d game, suddenly I saw the red light switch on the tablet to indicate it's charging, strange since it was hooked up to power and was already fully charged, and another test battery was around 40% and I charged to around 80% I rebooted the tablet and the battery was at 40% again!, so thinking my battery died I re-hooked up the stock cable and charged to 80% rebooted again and battery was 80% , narrowed it down to the cheap dx.com cable not supplying enough amps or some short in the cable, this is when I decided to make my own cable.
In my post above, The USB cable I was using I ended up taking apart the usb male connector and found out although the cable was decent quality copper wires.. where it was making the connection at the USB male end the connector only had little push pins puncturing through the wire (two little metal prongs), they weren't soldiered or anything so I guess it was another cheap cable .
So I searched for another cable, finally I found an older usb cable that none of my devices use anymore, this cable actually had a copper metal shield I just connected red and black, left green and white alone not connected to anything, so far it is operating like the stock cable when fully charged I can run full brightness , cpu at fullspeed, and 3d game without the charger light on the tablet going on (I assume this means the tablet is getting enough power from the dc port and doesn't need to switch to battery), I haven't had time to charge the device with the cable yet, but I'm assuming it will work like intended.
I guess they don't make cables like they used to.
hey guys you can check this site out http://techno-fix.com/ . i found my pinout searches there. there are very usefull things
no computer recognizes the tablet. no notification or warning when usb is connected to pc. only charging .
i also noticed that the tablet does not charge when its off. but charges fine when switched on. what can i do to resolve thsi issue
It should charge regardless on or off. Use this tool, it will tell you tablet is drawing current properly, the charging current should be around 1.5 Amps with working USB cable and charger.
https://www.ebay.com/sch/i.html?_fr...us+.TRS1&_nkw=usb+voltage+tester&_sacat=92074
USB connector has separated pins for data and charging. So it's normal if a tablet can charge but not data transfer or vice versa.
USB connector is cheap, only around 50 cents but you should know how to solder. A repair shop may charge you more than $50 to replace this 50 cents USB connector.
It takes only 5 to 10 minutes to change the USB port.
Hello all,
First thread here and hoping you guys and girls with more experience can help.
Basically I am fitting my nexus 7 2012 in my car but its got the common charging problem where my battery drains faster than I can charge it.
I have ordered a new USB port strip as I've read that can fix it and fingers crossed with that.
My problem/requirement:
1. I want to charge the tablet via the usb port using a hardwired 5V 2A device this will be plugged into a otg y splitter which is then plugged into the tablet.
2. The USB A side of the splitter I want to connect to my cars ECU (it has a USB port) so I can read the data on that (basically a very expensive memory stick)
I wanted to confirm that this would work and id be able to read data at the same time as charging it.
I also wanted to double check I'm not somehow going to send my 5v 2a power down into my ECU and set it on fire
On a side note, if my new USB port replacement doesn't solve the issue of charging the tablet i will have to remove the battery and hardwire it in, will i still be ok with using the USB port for the ecu while charging hardwired with no battery?
Kind Regards
Tim
Getting any USB 2.0 device to take current while hosting is tricky.
Usually it involves talking directly to the PMIC (power management IC).
If it's a fixed installation, why not remove the battery?
It will avoid the grief of the battery swelling up, which is not too unusual for things plugged in all the time.
I've been using a Nexus 7 (2013) for a few years, but just charging on USB.
It started falling out of its nice holder.
That's when I realized that the battery was all puffed up making the back convex.
I cut off the battery cell itself on the metal tabs and soldered in wires to a 4 V 2 A supply.
I found out that the BMS is a bit balky, it refused to turn on.
So I connected it to USB to "charge" it for about 10 seconds.
Then I could turn it on (without the USB).
Ok, I could have bypassed the BMS entirely but that can be a whole 'nother can of worms too.