Charging Safety Issues - Nook Color General

Is it safe to charge the Nook Color from a PC USB port? I tried using a iphone charger and I think it melted XD
So....I'd rather not melt my USB ports. :/ Or Blow up the nook!
Anyone have information for this?

I charged mine on an ungrounded extension card cinnected to a possibly unregulated outlet, and it broke the charger plug permanently. Burning smell and high heat and all that stuff.
Probably not my best idea. But I am not gonna say I think it happens to anything but the nook charger. That setup hasn't damaged anything else before or since.

Locklear308 said:
Is it safe to charge the Nook Color from a PC USB port? I tried using a iphone charger and I think it melted XD
So....I'd rather not melt my USB ports. :/ Or Blow up the nook!
Anyone have information for this?
Click to expand...
Click to collapse
When connected to a PC USB port the Nook will only detect that it is data USB connection and not a pure charger and will only try to draw 500mA which is the standard USB current limit. Under these conditions the Nook will only charge very slowly particularly if it is active with the screen lit.
When connected to a real charger like the Nook charger that has the data lines shorted to indicate it is a pure high power charger then the Nook will attempt to draw up to 2000mA. Any charger worth its salt will supply whatever it can and protect itself against overheating. Cheap and nasty chargers could potentially have overheating problems.
I have successfully used other chargers in place of the standard one. E.g a HP Touchpad charger and a car 2A USB charger.

Avoid this compatibility problem by using a standard micro USB cable when charging with a charger other than the standard NC charger. I charge my NC all the time with one of my numerous HTC plug-in chargers and a standard micro USB cable.

mr72 said:
Avoid this compatibility problem by using a standard micro USB cable when charging with a charger other than the standard NC charger. I charge my NC all the time with one of my numerous HTC plug-in chargers and a standard micro USB cable.
Click to expand...
Click to collapse
So using a regular micro usb cable will allow safe charging?

Locklear308 said:
So using a regular micro usb cable will allow safe charging?
Click to expand...
Click to collapse
Here is how I think it works.
Nook will only request up to 500mA charge rate if it detects that the cable is plugged into a regular USB port like on a PC with data connections. This is irrespective of whether you use the B&N cable or an alternative microUSB cable. There is almost 0 risk in this arrangement.
If the Nook is connected via a standard microUSB cable to a charger that signals it is a high power charger by having shorted data lines then it can get up to around 1000mA of charge from it.
If the Nook is connected via the B&N cable to a charger that signals it is a high power charger by having shorted data lines then it can get up to around 2000mA of charge from it. This is just because the B&N cable has extra voltage supply pins at the microUSB end and tries to spread the load to avoid stressing the individual pins with two much current. Without these extra pins it will not request the extra current through them.
In both the second and third case it is possible that a poorly designed charger could signal the ability to supply the higher current and then suffer because it did not have the overload / over-heating mechanisms to deal with it. One could argue that evolution should kick in at this point and destine this type of charger to the well-deserved scrap heap

bobtidey said:
Here is how I think it works.
Click to expand...
Click to collapse
Well, that's sort of close.
But the NC doesn't "sense" anything about the charger. The stock NC charging cable with the light-up horseshoe has the pins shorted and is also a slightly different connector type such that it cannot be plugged into a normal micro-USB on a device besides a NC. So if you plug THIS CABLE into the NC, then it will draw 2A from whatever is plugged into the other end of the cable. If the thing on the other end of the cable is the NC charger, you are in good shape, since it can safely deliver 2A of current. If you plug the other end of the NC stock cable into an iPhone wall charger or a computer USB port, some other generic wall charger, then it will likely draw more current than the charger or port can safely deliver and may damage the charger or cause a fire.
If you use a standard micro-USB cable, regardless of what charger you use (including the stock B&N charger), it will only draw about 500mA of current and charge the NC more slowly, but it will work safely with pretty much any generic USB port either on a computer or a run of the mill USB wall charger such as those that come with nearly every Android phone on the market, or a charge dock, USB cigarette lighter adapter for your car, etc.
So the key is: use the B&N stock NC CABLE ONLY with the stock B&N wall charger. Use a generic micro-USB cable with any charger including the B&N wall charger. It's all about the cable.

mr72 said:
Well, that's sort of close.
But the NC doesn't "sense" anything about the charger. The stock NC charging cable with the light-up horseshoe has the pins shorted and is also a slightly different connector type such that it cannot be plugged into a normal micro-USB on a device besides a NC. So if you plug THIS CABLE into the NC, then it will draw 2A from whatever is plugged into the other end of the cable. If the thing on the other end of the cable is the NC charger, you are in good shape, since it can safely deliver 2A of current. If you plug the other end of the NC stock cable into an iPhone wall charger or a computer USB port, some other generic wall charger, then it will likely draw more current than the charger or port can safely deliver and may damage the charger or cause a fire.
If you use a standard micro-USB cable, regardless of what charger you use (including the stock B&N charger), it will only draw about 500mA of current and charge the NC more slowly, but it will work safely with pretty much any generic USB port either on a computer or a run of the mill USB wall charger such as those that come with nearly every Android phone on the market, or a charge dock, USB cigarette lighter adapter for your car, etc.
So the key is: use the B&N stock NC CABLE ONLY with the stock B&N wall charger. Use a generic micro-USB cable with any charger including the B&N wall charger. It's all about the cable.
Click to expand...
Click to collapse
Sorry. That's not true.
The B&N cable behaves like a standard USB data cable. It does not have the data pins shorted. You can use it to plug the Nook into a PC and transfer files. This would not be possible if the pins were shorted in the cable anywhere. The only difference between the B&N cable and a standard one is that is has extra power pins on the microUSB end in a deeper connector that are just used for spreading the charging current.
The B&N charger like other high power USB chargers does have the data lines shorted in it and that is what the Nook sees and causes it to switch into high current charging mode.
You can see all this in operation with a Battery monitor App like "Battery Monitor". When the Nook is connected to a data port via the B&N or other cable then the charging mode is USB and will draw up to 500mA. When it is connected via a standard cable to a charger like the B&N then it will say AC charging mode but will only draw around 1000mA (not limited to 500mA). When it is connected to the charger via the B&N cable it will also say AC charging mode but will now draw up to 2000mA as the extra pins are available.
Note that these currents are the maximum drawn in these modes. The actual value drawn depends on the state of the battery. Also they are what the Nook attempts to draw from the charger. It can't force the charger to supply 2A and any decent charger (which is most in my experience) will only supply what they can safely or will shut down if they experience overheating.
I safely use the B&N cable with a variety of chargers. I also use it to connect to PCs for data transfer and background charging (at 500mA). I also use other USB cables with both the B&N charger and with other chargers. You only get full 2A charging by using the B&N cable with a charger with data lines shorted that can supply 2A OK.

bobtidey said:
Sorry. That's not true.
The B&N cable behaves like a standard USB data cable. It does not have the data pins shorted. You can use it to plug the Nook into a PC and transfer files. This would not be possible if the pins were shorted in the cable anywhere. The only difference between the B&N cable and a standard one is that is has extra power pins on the microUSB end in a deeper connector that are just used for spreading the charging current.
The B&N charger like other high power USB chargers does have the data lines shorted in it and that is what the Nook sees and causes it to switch into high current charging mode.
You can see all this in operation with a Battery monitor App like "Battery Monitor". When the Nook is connected to a data port via the B&N or other cable then the charging mode is USB and will draw up to 500mA. When it is connected via a standard cable to a charger like the B&N then it will say AC charging mode but will only draw around 1000mA (not limited to 500mA). When it is connected to the charger via the B&N cable it will also say AC charging mode but will now draw up to 2000mA as the extra pins are available.
Note that these currents are the maximum drawn in these modes. The actual value drawn depends on the state of the battery. Also they are what the Nook attempts to draw from the charger. It can't force the charger to supply 2A and any decent charger (which is most in my experience) will only supply what they can safely or will shut down if they experience overheating.
I safely use the B&N cable with a variety of chargers. I also use it to connect to PCs for data transfer and background charging (at 500mA). I also use other USB cables with both the B&N charger and with other chargers. You only get full 2A charging by using the B&N cable with a charger with data lines shorted that can supply 2A OK.
Click to expand...
Click to collapse
Well I can say that using an ipod/iphone charger is a BAD idea haha. I shall stick to the normal charger :]

Locklear308 said:
Well I can say that using an ipod/iphone charger is a BAD idea haha. I shall stick to the normal charger :]
Click to expand...
Click to collapse
I agree it is good to stick to the B&N charger with B&N cable for best fast charging. The only reason not to is to reduce the number of chargers one is carrying or to provide alternatives like charging in a car.
I was pointing out that the issue is primarily around the chargers not around the cable. Your original question was about charging from a PC USB port and that is safe no matter what cable you use.
The case where the cable might make a difference is where a non B&N charger has the data lines shorted and will allow AC charging mode but is OK with < 1000mA (non B&N cable) but could blow up if it tries to deliver 2000mA (B&N cable). So, it is less risky if you use a non B&N cable when using a non B&N charger. Still a poor charger design if that is the case.

Related

[Q] Aftermarket microUSB cords?

I bought a 10ft aftermarket microUSB cord from monoprice for my e-ink nook since the one that comes with it is ridiculously short. Worked great with the original nook. Since then I've bought a nook color and went to charge it with the charger that came with the NC and my aftermarket USB cord. No go. None at all. Not even a little. I read here that the NC and the cord that comes with it is special in that it has more connectors to enable faster charging but I'd think any microUSB would at least charge somewhat. I hate non standard cords because I lose them so often. Am I stuck with the cord that came with the NC?
all my standard usb cords do charge my nc, but VERY SLOWLY.
Yeah, see thats what I thought would happen too. But when I plug it in with the aftermarket cord it doesn't charge at all. Doesn't even say its charging.
It won't say that it's charging but it is. Problem is, it barely does if you're using the device heavily.
Inspection of the microusb tips of a standard cable vs the nook color one should clearly lead you to the conclusion that the nook color's cable is special beyond just the LED. It has more pins in order to deliver more power needed to charge the nook. You must use the cable in conjunction with a power source capable of delivering 2 amps in order to charge the nook properly (meaning it will act similarly and just trickle charge with no charging indicator if you use the nook color cable in a computer's USB port).
To solve the short cable issue I purchased a USB extender cable instead.
Sent from my nook color using Tapatalk
It's important that the charger circuitry in the Nook recognize the charging, because overcharging is the worst thing you can do to a Li-ion battery.

Make non-motorola charger work?

So this is my first motorola and I had heard of the issues they have with non motorola chargers. Now I am experiencing it first hand. With the same ac charger I have charged many phones with and is capable of 1 amp output (D4 charger is only rated at 850 mA) my D4 struggles. With the device off it charged painfully slowly. While on it cannot even charge. It discharges while plugged in despite the charging indicator and reporting "charging (AC)" in status.
How does it know it is not a moto charger? Is it just about the resistance between the data pins? For most other phones shorting the data pins on the charger indicates to the phone that it is a high current charger and not a computer USB port. Is there a similar trick for motorola phones? I would rather not have to purchase an overpriced moto oem car charger. I have a perfectly fine 1.2 amp car charger soldered directly into my car's 12v system behind the dash. Can I make it work?
Thanks!
On a regular basis I successfully charge my D4 using both a charger from a Samsung Reality feature phone and from a B&N Nook Simple Touch, in addition to the one that came with it. I've also used a variety of car chargers.
Sent from my DROID4 using XDA
Actually, so far I have only one charger that had any trouble charging the phone (it was a $3 charger with 2 USB ports), but the $3 charger with ONE USB port works fine, as does the Nook Color charger, Blackberry charger, and Samsung charger I have tried it with, as well as both my old car charger and Lenovo's always-on charging port on their laptops.
JKingDev said:
So this is my first motorola and I had heard of the issues they have with non motorola chargers. Now I am experiencing it first hand. With the same ac charger I have charged many phones with and is capable of 1 amp output (D4 charger is only rated at 850 mA) my D4 struggles. With the device off it charged painfully slowly. While on it cannot even charge. It discharges while plugged in despite the charging indicator and reporting "charging (AC)" in status.
How does it know it is not a moto charger? Is it just about the resistance between the data pins? For most other phones shorting the data pins on the charger indicates to the phone that it is a high current charger and not a computer USB port. Is there a similar trick for motorola phones? I would rather not have to purchase an overpriced moto oem car charger. I have a perfectly fine 1.2 amp car charger soldered directly into my car's 12v system behind the dash. Can I make it work?
Thanks!
Click to expand...
Click to collapse
Not sure how it knows one way or the other. I've successfully used a few LG chargers to charge my D4. The only really hickup I've ran into is the usb cables from those lg chargers won't sync data to the phones when plugged into a computer, they'll still charge off the usb port but won't read as a usb connection to the computer.
Heh, captcha is trynply.
Every charger I've used, including an old charger for an EN-V, kindle, supplied, and various other phone chargers works just fine with this phone. Probably have a bad charger, guy.
Thanks for the replies. I guess I was wrong. My modded car charger works just fine. I guess its just time to retire the old charger that I have been using. I think it might be my old nexus one charger.
A more important question would be does the thing charge over computer-bound USB ports?
When you're without a charger, but there's a USB cable that fits your phone, sometimes a regular USB data port is the only that is around... even though it might take a really long time.
Try a computer bound USB port, then try your actual charger, again. Or do the hard reset (vol down plus power, hold until it actually does it), which is just like pulling the battery.
See how that goes.
Chris
RueTheDayTrebek said:
A more important question would be does the thing charge over computer-bound USB ports?
When you're without a charger, but there's a USB cable that fits your phone, sometimes a regular USB data port is the only that is around... even though it might take a really long time.
Try a computer bound USB port, then try your actual charger, again. Or do the hard reset (vol down plus power, hold until it actually does it), which is just like pulling the battery.
See how that goes.
Chris
Click to expand...
Click to collapse
It does in fact charge via USB port. In fact, it has a 'charge only' mode. Depending on how much juice your port puts out, and what you are doing with the phone, it will charge slowly/not at all, though.
from my experiences, the droid 4 will not accept lg microusb cables, the charging bricks work tho. i use a blackberry microusb on mine along with a Logitech and the stock moto ones. 1.2 amps is a bit high but not crazy sounding. personally, I charge at 1 amp.

alternate source of fast charger?

So I left my NC wall charger and cable in my hotel room in South Korea last weekend, and of course I am back home in TX with no way to charge besides normal microUSB, which takes forever.
Is there any source other than B&N for a high-speed (high current) charger and cable? The B&N one is like $25, which is not too bad, but I still would rather find an alternative if possible.
What you're looking for on the charger is something that's rated at 1.9A or better. Most made for the ipad are 2A. The only alternative I've made use of is a Belkin one they sell at Wallyworld for $20 bucks, (same type deal as you but I still had the cable and was still on the road). With the stock cable I get a full charge in about three hours and with a regular cable I get a full charge overnight. If I had to do it over I might have pushed my schedule a little harder and looked for a B&N so I would have ended up with a "spare" cable out of the deal.
mr72 said:
So I left my NC wall charger and cable in my hotel room in South Korea last weekend, and of course I am back home in TX with no way to charge besides normal microUSB, which takes forever.
Is there any source other than B&N for a high-speed (high current) charger and cable? The B&N one is like $25, which is not too bad, but I still would rather find an alternative if possible.
Click to expand...
Click to collapse
Bummer! I travel to S. Korea regularly in Jan/Feb and in early Aug. Team development programs with Samsung at their Cheonan S1 Training Center. Where do you travel to in S. Korea?
Where as finding an adequate charger seems easy enough, its the cable that's the problem. Has to be an official B&N cable for fast charging. A standard microUSB will charge very slowly. I've yet to find an aftermarket equivalent.
Has anyone checked out a touchpad charger? It looks like it's just a standard micro usb charge that puts out 2A. It seemed to charge my nook reasonably fast but I didn't let it get above 95% since I wasn't sure if it would hurt the battery. I'll have to do a better test to see how long it takes to charge
bitnerd said:
Has anyone checked out a touchpad charger? It looks like it's just a standard micro usb charge that puts out 2A. It seemed to charge my nook reasonably fast but I didn't let it get above 95% since I wasn't sure if it would hurt the battery. I'll have to do a better test to see how long it takes to charge
Click to expand...
Click to collapse
Here are the results of a very quick test that I just performed:
Nook Color running Mirage CM7 latest version (5/18)
Overclocked to 1100Mhz and interactiveX governer
Screen at 100% brightness
Battery Monitor Widget main graph screen displayed entire time
Logging set for every 60 seconds
Test lasted about 5min for each combination
Battery at about 70%
Nook charger & cable
- average reading of +892mA
- mV increased 3844mV to 4053mV
Touchpad cable & charger
- average reading of -335mA
- mV increased 3847mV to 3901mV
Touchpad cable & Nook charger
- average reading of -407mA
- mV increased 3847mV to 3888mV
Nook cable & Touchpad charger
- average reading of +1211mA
- mV increased 3826mV to 4081mV
So it looks like the Nook cable is the key. As long as you have a charger that puts out around 2 amps or so and the Nook cable, the Nook will fast charge. It actually charged faster on the HP charger (2.0A output vs 1.9A for the Nook charger).
I also tried a cheap data cable I had and it stated "USB charging" and the results were similar to using the HP cable but a bit lower on the mA readings.
I plan to run the test again using a high Amp car charger but I think the results will be pretty much the same.
The best combination for a super fast charge is the HP Touchpad wall charger and the Nook cable
Just call B&N, talk nice. They will either give you a new set, or set you up with an order. They gave one to me, 2 day ship too...
My cable broke last weekend. I went to a BN store, and they sell the cable without the charger for $15.
Sent from my NookColor using Tapatalk 2
I don't know about the fast charger, but the charger for a samsung cell phone (not a smart phone just a normal phone) phone will charge the nook. I've accidentally plugged it in and it worked. I've not used it for extended periods so can't speak to its long term ability to work.
joelgrice said:
[...] So it looks like the Nook cable is the key. As long as you have a charger that puts out around 2 amps or so and the Nook cable, the Nook will fast charge. It actually charged faster on the HP charger (2.0A output vs 1.9A for the Nook charger).
Click to expand...
Click to collapse
I've noticed that my NT on B&N firmware 1.4 will charge on a non-B&N charger, but that the charging status shown in settings always says "not charging". My NC on CM7.2 simply indicates it's charging. I don't know if the B&N status really matters or not, but it is finicky about the wall adapter. If/when you re-test, could you please note the battery status?
Meanwhile, I did some testing with a PowerGen 12v adapter. I was able to get the NT showing "charging (AC)" while using the 1A plug on the adapter with the B&N cable. Reading the little booklet that comes with it indicates that "some devices" can pull more than 1A off this plug, including the "HP touchpad, Kindle Fire". While charging, I did get the erratic screen issue while plugged in. With the B&N charger, the same cable didn't cause this behavior on the NT. Not sure what that means, but you basically can't use it while it charges with the adapter. The 2A plug, described as "for the iPad" shows "not charging" (but not discharging). Using a generic microUSB cable also yields "not charging".
I also tested a EZOPower 7800 mAh supplemental battery. I was able to get a NT showing "charging (AC)" while using the "S" plug, described as compatible with the Samsung P1000 (Galaxy Tab) with the B&N cable. The "I" (iPad) plug did not work. The battery itself does charge off any 1A USB source, and will charge external devices at full 2.1A power as it charges. This means you should be able to let this battery power your NC, while the EZOPower battery charges more slowly from a normal 1A USB 12 VDC or AC adapter. Once the NT is fully charged at full rate, the EZOPower battery will itself charge. There were no screen issues with this combination, and I could use the device as it charged (with the usual cautions about the fragile B&N cable, of course.)
I don't know if the distinction between "not charging" and "charging (AC)" actually means anything, but the B&N firmware seems to care, while CM doesn't.
The reason why people notice they need a stock NC cable to 'fast charge' is that While it appears at first glance to be a standard microUSB plug.... it is not. Go ahead, try and plug it into your cell phone (no, it wont hurt your phone). The NC 'microUSB' plug actually has many more pins than the standard 5 (Something up near 20 as I recall). There are the normal 5 upfront, then the rest as further back. When you plug it in to charge, one of the rear pins connects and can supply the 1.9A max charge current. That 1.9A pin is directly connected to the Power Mgmt chip and is the only way to get high current charge.
The <explicitvie delted) whole story
There are three pieces to this puzzle.
1) a high power 2amp / 2000ma USB charger
2) shorting the correct pins in the cable to let the device know it is connected to a high power charger
3) extra long 12 ping next gen micro usb cable.
Some details...
Not all 1.9 / 2amp chargers are actually 2 amps
Some are 2 x 1amp
Some are mis-represented
etc.
I have tried many...
Some are frauds
Some are designed by idiots.
Few actually work
Yes, this is a Ipad spec.
Shorting the data pins (2 to 3) is required.
Go on eBay and look up pwr+ usb filter.
This little USB type a male to female adapter
does just that
shorts the data pins
finally the cable...
There is a new type of micro USB 12 pin connector on the cable.
The other big side is standard 4 pin.
The micro connector is longer than a standard micro USB.
The are some overseas import cables that work.
A standard USB cable WILL NOT WORK.
PS:
using a standard charger and cable will work but takes 4x longer.
Charging while on will run the battery down.
Pretty much stay with genuine OEM parts.
Especially the cable.
Unless you are tech savvy.
Google 12 pin USB
You can source a good 2amp power supply.
You can use OEM Ipad chargers.
HP makes a good 2A charger. PN 157-10157
12V - Scosche big black 4" long job 2 port 2.1a + 1a
However you must short the data pins with the pwr+!
mail at lofthouse dot org

Fast charging questions

Been looking for a fast car charger as well as a second ac charger.
I do have questions about usb cables though.
Which is responsible for shorting out the data pins...the charger, or the cable?
Also, while experimenting with my stock charger, I noticed a couple.of things...
I have an old 9ft cable I had along time ago, as well as a 6ft usb3 extension cable.
Using the stock charger
With 9ft cable, I get 13% per hour
With usb3 ext + stock cable, I get 25% per hour
With just the stock cable, I get 35% per hour.
(These are all according to battery monitor widget)
Should I be looking for a specific type of cable as well? I would really like a long cable so even if I bought a second oem charger, I would like to buy a non stock cable.
swyped all these spelling errors from my galaxy note 2
finalhit said:
Been looking for a fast car charger as well as a second ac charger.
I do have questions about usb cables though.
Which is responsible for shorting out the data pins...the charger, or the cable?
Also, while experimenting with my stock charger, I noticed a couple.of things...
I have an old 9ft cable I had along time ago, as well as a 6ft usb3 extension cable.
Using the stock charger
With 9ft cable, I get 13% per hour
With usb3 ext + stock cable, I get 25% per hour
With just the stock cable, I get 35% per hour.
(These are all according to battery monitor widget)
Should I be looking for a specific type of cable as well? I would really like a long cable so even if I bought a second oem charger, I would like to buy a non stock cable.
swyped all these spelling errors from my galaxy note 2
Click to expand...
Click to collapse
You're probably referring to the charge-only usb cables with the data pins shorted out - it is the cable which has the data wires shorted out; the wall charger only uses 2 out of the 4 usb wires, so there's no need to have anything shorted out on the charger side.
It's useful to share what you have noticed, but the general idea is that the longer the usb cable, the more it would take to charge because the extra resistance along the cable which is created; in a similar way you lose current if you use any extenders, passive usb hubs etc - how much? it really depends on what you pick, you can have it calculated / measured. A higher gauge usb cable would give you faster charge times, so pick a quality cable, even if it's a non-OEM and you'll get similar results to the original cable.
tbukkos said:
You're probably referring to the charge-only usb cables with the data pins shorted out - it is the cable which has the data wires shorted out; the wall charger only uses 2 out of the 4 usb wires, so there's no need to have anything shorted out on the charger side.
It's useful to share what you have noticed, but the general idea is that the longer the usb cable, the more it would take to charge because the extra resistance along the cable which is created; in a similar way you lose current if you use any extenders, passive usb hubs etc - how much? it really depends on what you pick, you can have it calculated / measured. A higher gauge usb cable would give you faster charge times, so pick a quality cable, even if it's a non-OEM and you'll get similar results to the original cable.
Click to expand...
Click to collapse
but the OEM cable can also be used for data transfers, surely, it's data pins are not shorted out?
it is the charger that normally has data pins shorted, and I have modified a few chargers to achieve this.
In the OSmonitor app the is a misc tab that shows if you are charging from AC or USB, there must be a way of finding the charging current, on one of my old phones it was displayed in dmesg.
Dont forget that the % per hour will vary according to how full the battery is, slowing down as it gets more full.

12V Power Cord....

I needed a vehicle power cord for the Nook HD. Instead of picking up the Nook specific accessory, I picked up the regular charger figuring that I could use a 12V->USB(iPad) vehicle accessory and then just plug in the Nook HD cable.
Well, this doesn't work. I need to investigate but does anybody know if there's anything special about B&Ns vehicle->USB adapter?
Thanks,
John.
OK - any ideas on this one. Bought another type of power adapter (similar to this: http://www.amazon.com/Griffin-Powerjolt-Universal-Micro-Colors/dp/B0042B9U8Q) and when you plug in the Nook HD USB cable the green light comes on the bottom of the unit but Android still reports 'on battery'.
Same cable (original Nook HD cable) will charge the unit off a USB port or the Nook HD wall charger.
I'm confused as to why it doesn't work with 12V adapters.
John.
matthewsjl said:
OK - any ideas on this one. Bought another type of power adapter (similar to this: http://www.amazon.com/Griffin-Powerjolt-Universal-Micro-Colors/dp/B0042B9U8Q) and when you plug in the Nook HD USB cable the green light comes on the bottom of the unit but Android still reports 'on battery'.
Same cable (original Nook HD cable) will charge the unit off a USB port or the Nook HD wall charger.
I'm confused as to why it doesn't work with 12V adapters.
John.
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The 12v car charger specs are 5v @ 1amp=5 watts per port (P=IE). The BN car charger is probably 5v @ 2 amps=10 watts output. The Nooks are programmed for 1900 ma or 500 ma charging.
Yes, but if using a 1A port on the charger, the Nook should still be able to charge at the lower 500mA rate. Yes, it would be slow but the Nook doesn't even start to charge.
Plugging the same cable into a computer USB port.... it starts to charge.
John.
As it is with the case for most USB powered devices, you'll need to find a charger or modify the existing one so that has the USB Data+ and Data- pins shorted together. I have verified this to work.

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