hi guys, I soldered a 5v charger's +5v & ground wires to a female USB port, then connected to the mini-usb port of the Atom, external power was detected but it doesn't charge, what else do I have to do to trigger charging? thanks!
ashy said:
hi guys, I soldered a 5v charger's +5v & ground wires to a female USB port, then connected to the mini-usb port of the Atom, external power was detected but it doesn't charge, what else do I have to do to trigger charging? thanks!
Click to expand...
Click to collapse
Interesting. I've noted similar issues, I first thought it was to do with the power current capacity however I'm not so sure now. What I did find was that if I plugged in the usb plug first and then turned the charger power on (e.g. car charger 850mA) then it would charge. However the original charger worked any which way. Also turning off the screen would result in slow charging even when it said not! Does this help?
There is some problem in oem battry driver, you can google to find the driver hotfix.
sorry for my BAD english..
You must give two other pins short with resistor as i remember. This is in order to simulate USB connectivity, which original charger do.
This is for HP Ipaq rw6815 I have..
more info you can find in below links it's for other devices, but the workaround is the same:
http://ecece.com/info/ipaqcradlemod/ipaqcradlemod.html
I don't think below method i safe enough, I think it's not a wise decision to shorten your data pins, but obviously work with iphone
http://carlhutzler.com/blog/2009/07/28/usb-hub-as-an-ipodiphone-charger/
Long story, but I bought a used Fascinate without the stock charger.
Could someone install, or hopefully already have, the "Battery monitor Widget". Then plug their Fascinate into the stock AC charger or stock car charger (NOT the USB on a PC), and let me know what the usage (ma) reading is on the widget.
More of the story. Basically, I know that at least on older HTC devices they would pull more charge/operating power from a non-USB connection. Actual USB is limited to 500ma load, so they had a system that kept the current low on USB and bumped it up for non-USB. All of the non-stock cables that I have show a very low charge rate on the Fascinate. It in fact runs the battery dead while on charge and I use the phone with GPS software.
i can tell you the factory charger is putting out 5v at .7a(700ma).
Mylt1 said:
i can tell you the factory charger is putting out 5v at .7a(700ma).
Click to expand...
Click to collapse
Thanks, it is good to know that they stick with 5V. But it just means that it can put out up to 700ma. I suspect it is using about half of that.
If you can cut open the wires and insert and ammeter in series, that is what I need to know.
edit: nvm ...
Found it. I have been searching for this for a couple of weeks and just now stumbled on the right search keywords.
For anyone that wants to know.
The Fascinate appears to pull about 350ma from the 5 volt supply normally. But, if you short out the USB D+ and D- lines in the charge connector, the charge current goes up to about 600ma.
That will help me not have a dead battery when using the GPS.
Oh, as an added bonus, you don't get the USB / Debug notification.
I have TPT for 10 days now.
I have usual iisue with USB charging. When used like standard smartphone = put it to charger overnight. Not usable anyway. Charge rate about 5% per hour, which means 20 hours per full charge???
I even consulted it with local technical support. I was adviced to buy docking station with external power adapter .....
So ... I took regulated power supply, made a USB socket connected to it and started to measure
.. and look what I found
When device is switched on, usb power oscilates sligthly under 1000 mA. It is NOT using all available power of 2 Amps of stock power adapter!!!!!
But ... when I power the device off using power button. The current goes down to 300mA for about 5seconds and then raises to full 2 A!
Conclusion? It seems like control issue of the charging ciurcits. What if we can enable full 2A power even when turned on? SW issue?
Is there any chance, how to instruct internal power circuity to use all available power? ADB?
Well I guess that explains the slow charging that people have been reporting. I picked up a dock for my tablet from amazon for about $30 shipped. Now I just put my USB charger in my bag for when I am out and about and dock it when I get home. That being said when I was charging via USB before I had the dock, a full charge seemed to take about 6 hours or so.
As for your question regarding modifying the input charging rate while powered on, I am not sure that can be done via ADB. I am taking a stab in the dark here, but I wouldn't be surprised if the charging rate was hard coded into the power circuit. Which would make some sense so as not to draw to much power if someone wanted to try and charge their tablet while having it plugged into a laptop or USB hub. I am not sure if it has an auto sense capability to determine whether or not it is charging via USB from a port or from the power adapter. I do know when I hook it up to my computer to transfer files it offers me the option to charge via USB, but I think that is a software thing and not hardware. I could be wrong. Maybe if we had access to the board schematics I could figure out. I can read schematics and might be able to figure it out.
Any chance you could get a proper reading via the docking port on the tablet? I would be curious to see if it is always at 2A. I haven't counted the pins but I don't see why you would need more than VCC+, VCC-, GND and maybe a sense line. But I know there are more than 4 pins.
Sent from my ThinkPad Tablet using xda premium
I would say this is a SW issue. Maybe if we had the kernel source code someone could cook up a custom kernel with that control feature tweeked.
Temetka said:
~
Any chance you could get a proper reading via the docking port on the tablet? I would be curious to see if it is always at 2A. I haven't counted the pins but I don't see why you would need more than VCC+, VCC-, GND and maybe a sense line. But I know there are more than 4 pins.
~
Click to expand...
Click to collapse
The best thing to use is a watt meter if anyone wants to pursue this.
My findings indicated that the dock has a similar issue as the USB charger when the TPT is on.
Maximum current allowed at the dock connector was measured at just over 1A . Dock should charge the battery at a maximum rate of just over 1% per minute provided the battery charge level is below 70%. So if you discharge the battery to around 50% and compare charge rates you should see the difference between TPT on/off.
Can someone verify that the Nexus 7 can operates perfectly fine with the battery removed and only powered by the USB cable? I've read some threads eluding to this, but no one has confirmed. Mine is in the dash of my car so i cant verify this myself. If someone can. that would be amazing! Thank you.
look at the thread right below yours.
Old Guy said:
look at the thread right below yours.
Click to expand...
Click to collapse
I saw that thread, i was still a bit confused as they were talking about USB DAC and other devices hooked up to me.
I want to make sure data can still be transferred from the same USB cable and such.
Yes, it's possible, but has some side-effects
Yes, it's possible to power the Nexus 7 without battery from a USB-cable, but it involves sending power directly to the battery connection inside the Nexus 7, and it seems to have some side-effects.
The battery is a one-cell lithium polymer, which has a max charge of 4.23 V. I hoped the Nexus wouldn't fry when connecting 5 V, and it has worked fine the few minutes I've tested it. No smell of burnt electronics
Here is what I did:
Tear off the tape around the battery cable. You'll see it's soldered to a pcb-board, and the two black and two red wires are soldered together. The two wires in the middle is probably some kind of data-connection to the battery. Will investigate this further later.
Then I soldered loose the cables, so I could use the battery-connector, and soldered both red and black wires to red and black wires in a USB-cable. Drilled a hole in the back-cover right below the NFC-antenna. The back-cover is filled with all sorts of antennas, so scratch carefully with a knife before drilling. Attached some pictures of the process.
Side-effects I've noticed so far:
- It thinks the battery is at 0% and not charging.
- The clock is reset when you turn off the power. But if you have internet it will update from NTP within a minute or so.
- My computer (OS X) can't detect it anymore. So I suspect it doesn't work in USB device-mode anymore, but I'm able to connect a USB-keyboard with an OTG-cable, so it seems to work in host-mode.
Does anyone else have any experience with this, or any ideas why it doesn't work in device-mode? I'm considering adding a small connector so I can use the two extra wires from the battery to the data-wires of the USB-cable (and disconnect when not in use), and then solder a USB female cable to the original battery. That way I can (hopefully) connect the Nexus 7 to my computer when needed, and possibly analyze what the two extra wires is actually used for.
I have CM for Android 4.2, and Timur's USB-rom, but it's probably not needed for this hack, and I will probably install a stock rom if I get this working properly.
Be careful, and don't blame me if you fry your Nexus (or anything else). Be sure to turn off any fast-charge hacks when the battery is disconnected.
Old Guy - look at the thread right below yours
Click to expand...
Click to collapse
Threads are sorted by last post in each thread, so it's impossible to find which one you are referring to. Do you have an url?
Theory worked
I managed to connect the Nexus 7 to my computer again
I'm considering adding a small connector so I can use the two extra wires from the battery to the data-wires of the USB-cable (and disconnect when not in use), and then solder a USB female cable to the original battery. That way I can (hopefully) connect the Nexus 7 to my computer when needed, and possibly analyze what the two extra wires is actually used for.
Click to expand...
Click to collapse
Can confirm that this works. I didn't have any small connectors, so I hot-glued one header-pin and a female connector for a header pin on the data-wires in the USB-cable. Doesn't look good, but it works
When I have it in the car, I disconnect the header-pins on the USB-cable, and connect it to an USB power-source. When I need to connect it to the computer, I connect the header-pins and connect the battery (with the female USB-cable), and a regular USB-cable to the computer.
Sorry to bring up an older thread, but it sounds like the White and Yellow wires of the battery are for data?
if so, if I applied 3.7-4.2 volts on the battery connection and then still had a 5v connection on the USB would this work?
I would like to use Timur's ROM, and have power applied when my car is off (fixed install) for deep sleep and then apply the 5v when the car is on to bring it from the deep sleep. the issues would be faking it to not charge which I am guessing would mean to set the battery input to 4.23 volts to show as being fully charged. then when key on, the 5v would take over and you would still have the 4.23 applied at the battery connection ( probably have a diode on the + side to keep from injecting voltage to that supply
Has any one completed something like this?
The problematic usb port finally gave up on my Nexus 7 (2012). I've opened up it up, connected the black and red wires from a cut usb cable to the 1st and 4th pogo pins without removing the battery. Now charging's fast and stable..
Added: Tried 5v2a charging, it doesn't melt anything.. Fully charged in just slightly over1 hour.
This thread has been great help and a motivator for wiring my Nexus 7 to do a (permanent) dash install.
I've just removed the battery and wired it to a Pico-Box X5-ATX-180 carputer PSU with an adjustable voltage converter in-between to get around 3.9 volts to the tablet. Works great, but I found another drawback.
Like mentioned in a post before me, the battery status will show 0% which I thought wouldn't be too big of a problem. However, at the moment there is an Android update (4.4.3) available and when I try to update it first tells that the battery is too low and that I should connect a charger. So I did, but then it tells me too "wait for the battery to charge sufficiently".
So for anyone reading this wanting to do the same, know that you won't be able to update Android without a battery connected.
I have attached a photo of the tablet running without a battery for those interested.
Rutjes said:
This thread has been great help and a motivator for wiring my Nexus 7 to do a (permanent) dash install.
I've just removed the battery and wired it to a Pico-Box X5-ATX-180 carputer PSU with an adjustable voltage converter in-between to get around 3.9 volts to the tablet. Works great, but I found another drawback.
Like mentioned in a post before me, the battery status will show 0% which I thought wouldn't be too big of a problem. However, at the moment there is an Android update (4.4.3) available and when I try to update it first tells that the battery is too low and that I should connect a charger. So I did, but then it tells me too "wait for the battery to charge sufficiently".
So for anyone reading this wanting to do the same, know that you won't be able to update Android without a battery connected.
I have attached a photo of the tablet running without a battery for those interested.
Click to expand...
Click to collapse
You could use the factory image to update your nexus 7. It's just a bit more work.
Rutjes said:
This thread has been great help and a motivator for wiring my Nexus 7 to do a (permanent) dash install.
I've just removed the battery and wired it to a Pico-Box X5-ATX-180 carputer PSU with an adjustable voltage converter in-between to get around 3.9 volts to the tablet. Works great, but I found another drawback.
Like mentioned in a post before me, the battery status will show 0% which I thought wouldn't be too big of a problem. However, at the moment there is an Android update (4.4.3) available and when I try to update it first tells that the battery is too low and that I should connect a charger. So I did, but then it tells me too "wait for the battery to charge sufficiently".
So for anyone reading this wanting to do the same, know that you won't be able to update Android without a battery connected.
I have attached a photo of the tablet running without a battery for those interested.
Click to expand...
Click to collapse
What did you use to get the voltage down to 3.9 volts?
the exact thread I've been searching for.
Just completed by initial installation and now troubleshooting various problems.
The biggest being this battery scenario. So from what I've read in this thread is to use a DC-DC power switcher PICO for carputers and run that to the battery leads. How is the boot time though?
I've read that with a low battery, the kernal during bootup takes longer for checks to occur?
I have an idea.....:
If we can switch 12VDC to 5VDC during switched (Key On Accesory) with a regulator.....
we should be able to do the same with a sepearate regulator to switch 12VDC to5VDC during constant (Key off) when the switch voltage is lost.
This would retain the time you mentioned gets lost. Also, how much mAh (current) do you get out of that PICO regulator to the battery leads? The TIMUR kernal for FI-mode wants 1800mAh at least. Currently I'm using a cigarette lighter DC-DC adapter that has 2 ports. (2.1A, and 1A). The Nexus 7 is currently connected to the 2.1A and my HUB is connected to the 1A.
any advice?
Thanks
rezmax said:
Just completed by initial installation and now troubleshooting various problems.
The biggest being this battery scenario. So from what I've read in this thread is to use a DC-DC power switcher PICO for carputers and run that to the battery leads. How is the boot time though?
I've read that with a low battery, the kernal during bootup takes longer for checks to occur?
I have an idea.....:
If we can switch 12VDC to 5VDC during switched (Key On Accesory) with a regulator.....
we should be able to do the same with a sepearate regulator to switch 12VDC to5VDC during constant (Key off) when the switch voltage is lost.
This would retain the time you mentioned gets lost. Also, how much mAh (current) do you get out of that PICO regulator to the battery leads? The TIMUR kernal for FI-mode wants 1800mAh at least. Currently I'm using a cigarette lighter DC-DC adapter that has 2 ports. (2.1A, and 1A). The Nexus 7 is currently connected to the 2.1A and my HUB is connected to the 1A.
any advice?
Thanks
Click to expand...
Click to collapse
Why go through all the trouble? Just snip off any USB cable and connect to the pogo pins.. This way, you can charge at pogo's speed with any wall charger and still bring your tablet anywhere.
Hi guys just wanted to report i used your trick on my nexus 7 and it worked perfectly!
I used this method to check if the problem was the battery or if the screen was dead and it turned out to be the battery!
Now i have another battery on the way from Ebay.
Thanks again good job!
Hi guys me again,
I want to update the software but it wont let me because battery is on 1% for ever.
BUT i was wondering, what would happend if i simultaneously plug in the mini usb to another usb charger?
would that create some sort of an insane weird circut and burn my tablet?
any thoughts?
thanks!
Im thinking to use the Nexus 7 in car without the original battery. Constant 4.2V from car battery via converter to nexus battery pins and using the usb with ignition to switch the tablet between sleep and normal state. One thing i would want to reuse is the temperature sensor in the Li-ion pack. Has anyone some idea if the two extra wires are directly connected to temp sensor or there is a circuit for it on the battery controller? If so how it could be reproduced so i could use this to monitor the temp in car for example or if anyone knows any usb dongles that i could use for monitoring external temp with android.
So now i hav tryed the nexus without the battery aswell. At first i applyed 5v directly to the little black battery connector. tablet worked but showed 0%. Then tryed desoldering the batteryback from the little circuit and applyed 5v to the actual battery connectors on the circuit. It shows 100% battery and works and also the temperature sensor is working. One issue is that i need to plug in the charger before connecting the circuit to the motherboard, maybe the charger im using is just too weak that cant get the voltage up or something. And another thing is that i left it plugged in for the night and now the percentage goes down slowly as it would be discharging. havent figured out why that is. Maybe someone has tackled this before also?
freakadell said:
So now i hav tryed the nexus without the battery aswell. At first i applyed 5v directly to the little black battery connector. tablet worked but showed 0%. Then tryed desoldering the batteryback from the little circuit and applyed 5v to the actual battery connectors on the circuit. It shows 100% battery and works and also the temperature sensor is working. One issue is that i need to plug in the charger before connecting the circuit to the motherboard, maybe the charger im using is just too weak that cant get the voltage up or something. And another thing is that i left it plugged in for the night and now the percentage goes down slowly as it would be discharging. havent figured out why that is. Maybe someone has tackled this before also?
Click to expand...
Click to collapse
You supplied power to the protection circuit? I'm surprised that worked.
The battery is probably going down because the protection circuit is designed to prevent over and under voltage. Since you're feeding it 5V and a lithium battery is supposed to max out at about 4.2V it must be trying to lower the voltage somehow. The percentage going down is probably nothing to worry about, but I'd strongly recommend connecting to the battery connector instead, and only connecting it like this when you need to have a certain percentage to do a system update etc. Also be careful with the bare battery, if the two pins short it could catch fire.
Hi i tried that works ,however it doesn't boot when powered i have to turn it on pressing power button,any idea why?
As a car dash its pretty useless now
Just a quick message that I have managed to power my nexus 7 2012 from a USB cable connected to the circuit board that was attached to my dead battery. Battery level indicator is permanently at 100%.
Sort of like the above it involves using the battery circuit board but it is disconnected from the battery.
Step 1: Strip back battery wrapping revealing the board attached to the connector cables (that connects to Nexus 7)
Step 2: Cut the metal strips going from the circuit board to the actual battery part
Step 3: Solder USB cable Positive wire to board pad labelled VP and Negative to pad VG(? not 100% on last one, but it's the other pad)
Step 4: Solder short wire from VP pad to other side of the board onto the ++ pad (that goes to the red wires then connector)
Step 5: Wrap board up with elec/other tape to avoid shorts
Step 6: Connect up and power on
Not sure why the last wire is needed but it didn't work for me without it.
Next step for me is to wire it to the onboard micro-usb
Where is the ++ pad ??
dribbleboy said:
Step 4: Solder short wire from VP pad to other side of the board onto the ++ pad (that goes to the red wires then connector)
Not sure why the last wire is needed but it didn't work for me without it.
Next step for me is to wire it to the onboard micro-usb
Click to expand...
Click to collapse
Where is the ++ pad mentioned in step 4 ? Can you post some pictures ?
I used ordinary low charge cable to charge my Note 4. Then when I tried to charge it with the original Fast charge cable it wont work any more.
Does this mean that the fast charge cable is not working any more?
Or I need to do something with the setup?
Please advise
zyad1802 said:
I used ordinary low charge cable to charge my Note 4. Then when I tried to charge it with the original Fast charge cable it wont work any more.
Does this mean that the fast charge cable is not working any more?
Or I need to do something with the setup?
Please advise
Click to expand...
Click to collapse
A cable is a cable. There aren't fast charging cables or slow charging cables .... Try to go in Battery settings and reactivate Fast charging
qwertyup88 said:
A cable is a cable. There aren't fast charging cables or slow charging cables .... Try to go in Battery settings and reactivate Fast charging
Click to expand...
Click to collapse
Erm... Not 100 % correct.
Cables DO make a difference. We're trying to transfer at least 2 A of current via thin wires. That needs a specific cross section of the wire; many USB cables use internal wires thin like a human hair, which could cause problems like overheating or simply reducing the charging current, resulting in longer charging durations.
Samsung doen't provide that thick, stiff cable with their high-amperage power supplies without a reason.
So please stick with the cable provided with your power supply; it really is the best choice, keeping you and your Note safe.
And: Nothing wrong with fast charging !
Zyad: Try charging your Note with the original power supply using the original cable, but charge the phone switched off for the first time.
After charging, switch on, use your phone till the battery is down again. Then switch back to fast charging.
Could not have said that better myself.