Database Develop

Alternative 5V chargers (currency?)

Hi, I'm really a noob when it comes to electronics. For all I know, when a cable fits it should work
I have a couple of microUSB chargers laying around. They all have an output of 5 Volt but they output a currency that differs from the standard charger (1A).
What is the "golden rule" wrt currency? Are chargers with a currency that is less than 1A save?

current is not pushed, it is pulled by your device as necessary. voltage is pushed, so correct voltage,5V in this case, is very important. As for the current, if the charger can't supply enough current with that voltage it will get hot and cause problems. i.e., you should have a current greater or equal to your original charger and same voltage. this applies to ALL of your electronics.

ozkaya said:
current is not pushed, it is pulled by your device as necessary. voltage is pushed, so correct voltage,5V in this case, is very important. As for the current, if the charger can't supply enough current with that voltage it will get hot and cause problems. i.e., you should have a current greater or equal to your original charger and same voltage. this applies to ALL of your electronics.
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Thank you very much for this explanation. What do you think, a 5v charger with a current of 850mA will that cause big problems when I use it just accidentally to charge my device.

appelflap said:
Thank you very much for this explanation. What do you think, a 5v charger with a current of 850mA will that cause big problems when I use it just accidentally to charge my device.
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It probably wouldn't be a lot of problems, if you really have to do it, charge it when the screen is turned off, so that you will need less current.

You can charge without risk with any USB charger. Unless the charger "signals" that it can supply more than 500mA by having the 2 USB data pins shorted, the HD2 won't pull more than 500mA, which is the minimum a USB charger must be able to supply.

"Golden rule" - If You have 5V its safe for Your phone, current level is determining the time that You need to charge battery.
Kilrah sad that HD2 'pull' no more than 500 mA - ok, if this is true ( i believe it is , he always make some test for it ) original charger needs about 2h, with 250 mA charger it will take more than twice of that time - 4h ( it's not fully linear )
@Kilrah - did You test what's power ( current taken ) consumption during charging ? it's really only 500 mA ? if so, than why HTC use 1A charger ? usually safety rules are about 15 - 30% more than max current needed.
0.5 A + 30% = 0.65A , so why 1A ?

The minimum current what HD2 accepts is 500mA because this is the USB standart.
If the supply could deliver more than 500mA the HD2 will take it up to 1000mA. The maximum current which the HD2 can use is 1A (1000mA).
So if your charger can deliver 5V and 2000mA the HD2 will limit the current to 1000mA. So you can use a charger, when the voltage is 5V and the current at least 500mA.
The push pull principe in the post before is correct, because the charger is a voltage source and not a current source.

I am already enjoying the benefits of proposed standardisation of phone chargers to micro usb pin. Since I upgraded with HD2 from Nokia N97 I am using the nokia wall chargers as well as well as car charger. I didnt have to buy new charging accessories for this mighty HD2.
By the way would the Nokia data cables (micro usb) be able to sync data when used with HD2. Havent tried yet.....

afropolak said:
@Kilrah - did You test what's power ( current taken ) consumption during charging ? it's really only 500 mA ? if so, than why HTC use 1A charger ?
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As said, IF the 2 USB data pins are NOT shorted (that's how it is by default on <500mA/3rd party chargers, or on a PC), the HD2 will limit the current it pulls to ~450mA.
IF they are shorted (on chargers that support higher current like the supplied one) the HD2 will pull more. With the supplied charger it's about 850mA, with a 3rd party "800mA" Chinese charger that didn't have the pins shorted but was modded to have it done, it pulls about 650mA.
PlayStation said:
By the way would the Nokia data cables (micro usb) be able to sync data when used with HD2. Havent tried yet.....
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Micro USB is a standard, so every micro USB cable should be the same. If not, you've got a botched knockoff.

so how do you short the cable assuming I get a car charger without a USB to micro USB cable and sourced my own cable from a parts bin that was probably for computer usage?

cheahcl said:
so how do you short the cable assuming I get a car charger without a USB to micro USB cable and sourced my own cable from a parts bin that was probably for computer usage?
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I don't think that would be a good move!
You would have to be certain of the regulation circuitry of the charger and it's ability to cope with the attendant initial draw of the battery when plugged in.
This will depend on the state of drain of the battery and the various functions in operation at the time on the phone.
At the moment of plugging in is when the draw will be highest and when any protection circuitry will be essential.
A well topped up battery will "draw" less than a depleted one and will continue charging on as little as 350mAh (again depending on what is running on the phone).
A very depleted battery may well not even start the charging process at such a level. That's why the HD2 comes with a 1000mAh wall charger!
The levels quoted for PC/Laptop USB power are nominal off load levels and will vary depending on any othe devices plugged in on the same bus supply.
So, with a PC that has a few attached USB devices, you may well NOT see 500mAh and as has been reported before, you can get battery depletion back into the USB port as other devices draw from the phone!
Always best to keep the battery topped up to prevent "charging strain" on the cells. This will maximise the capacity available when you need it for those longer periods of time.

Charging Safety Issues

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?
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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.
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So using a regular micro usb cable will allow safe charging?

Locklear308 said:
So using a regular micro usb cable will allow safe charging?
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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.
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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.
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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.
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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 :]
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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.

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.
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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
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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).
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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

NC charger

I was wondering where to get a charger for my NC, whether it be car or home, that will not be 30 like in the stores.

smayer85 said:
I was wondering where to get a charger for my NC, whether it be car or home, that will not be 30 like in the stores.
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Just search for ADP-H01 on the web. I have seen them as low as $16.

Good suggestion leapinlar, looks like I'm gonna acquire a spare soon.

The NC is a mature product, and anything worth talking about has been talked out. Search these NC forums (or just Google in general) for "nook color charger".
Here's one that's interesting: The OS makes a difference. Those using CM7 can charge using any 2.0 or 2.1A charger, with any cable (presumably of sufficient gauge to carry 2A). Those using stock ROM must use OEM charger & cable.
http://forum.xda-developers.com/showthread.php?t=1002332
I'm not sure about stock, since I converted my NCs OOB. But my experience (using CM7) is same as the OP in above-linked thread. I can charge with any 2A charger and standard cable.

e.mote said:
The NC is a mature product, and anything worth talking about has been talked out. Search these NC forums (or just Google in general) for "nook color charger".
Here's one that's interesting: The OS makes a difference. Those using CM7 can charge using any 2.0 or 2.1A charger, with any cable (presumably of sufficient gauge to carry 2A). Those using stock ROM must use OEM charger & cable.
http://forum.xda-developers.com/showthread.php?t=1002332
I'm not sure about stock, since I converted my NCs OOB. But my experience (using CM7) is same as the OP in above-linked thread. I can charge with any 2A charger and standard cable.
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Yes, you can charge, but not at the full rate. The charging block must have the two center pins shorted (d+/d-). Some charging blocks have that and some do not. If they are shorted, the nook might allow the block to deliver the full 2+ A rated on the block. But the cable must be able to deliver that much current. Only the stock cable can do that. It has extra pins (a total of 12) in the nook end of the connector to deliver that much. Regular microUSB cables do not have those pins. That is why nook cables have an end that look longer than standard cables. So the charging circuits in the nook sense the shorted data pins and the extra pins in the cable, then it turns on full charging. It does this for all roms. If it does not detect those two conditions, it assumes you are connected to a USB port and limits charging current to 500MA regardless of block capacity.

leapinlar said:
Yes, you can charge, but not at the full rate. The charging block must have the two center pins shorted (d+/d-). Some charging blocks have that and some do not. If they are shorted, the nook might allow the block to deliver the full 2+ A rated on the block. But the cable must be able to deliver that much current. Only the stock cable can do that. It has extra pins (a total of 12) in the nook end of the connector to deliver that much. Regular microUSB cables do not have those pins. That is why nook cables have an end that look longer than standard cables. So the charging circuits in the nook sense the shorted data pins and the extra pins in the cable, then it turns on full charging. It does this for all roms. If it does not detect those two conditions, it assumes you are connected to a USB port and limits charging current to 500MA regardless of block capacity.
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I have found that as long as I have my charger cable, I can use any "block" to charge. I generally will use my IPAD block and that charges it just as quickly. So instead of having to spend 30 bucks for a new nook block, I can just use my cable and a different block. its very convenient.

IPAD bricks provide 2.0A and the B&N ones are rated at 1.9A. It boils down to the (semi-)proprietary cable.

ufkal said:
I have found that as long as I have my charger cable, I can use any "block" to charge. I generally will use my IPAD block and that charges it just as quickly. So instead of having to spend 30 bucks for a new nook block, I can just use my cable and a different block. its very convenient.
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iPad chargers also have the data pins shorted.

leapinlar said:
Yes, you can charge, but not at the full rate. The charging block must have the two center pins shorted (d+/d-). Some charging blocks have that and some do not. If they are shorted, the nook might allow the block to deliver the full 2+ A rated on the block. But the cable must be able to deliver that much current. Only the stock cable can do that. It has extra pins (a total of 12) in the nook end of the connector to deliver that much. Regular microUSB cables do not have those pins. That is why nook cables have an end that look longer than standard cables. So the charging circuits in the nook sense the shorted data pins and the extra pins in the cable, then it turns on full charging. It does this for all roms. If it does not detect those two conditions, it assumes you are connected to a USB port and limits charging current to 500MA regardless of block capacity.
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In my experience there are actually 3 possible max charging rates into the Nook Color
1) USB mode where a charger / cable doesn't have shorted data lines (including PC) - Max 500 ma
2) AC mode (half) where a charger does have shorted data lines but a standard USB cable is used - Max 1000ma
3) AC mode full where a charger has shorted data lines and a Nook proprietary cable is used with the extra power pins - Max 1900ma

>In my experience there are actually 3 possible max charging rates into the Nook Color
How did you measure the differing DC current? Clamp meter? In-line resistor?

Battery Widget in the Play Store will tell you near real time.
Rodney

rhester72 said:
Battery Widget in the Play Store will tell you near real time.
Rodney
Click to expand...
Click to collapse
That's what I have used and it seems to tally well with rate of charge of the battery. It indicates AC or USB charging (shorted / non-shorted data lines) and showed 1000mA in AC mode with standard USB cable as opposed to 1900 with Nook cable.

>Battery Widget in the Play Store will tell you near real time.
Can you provide the developer name? There are many battery widgets, and those I've tried don't indicate charging level. TIA.

e.mote said:
>Battery Widget in the Play Store will tell you near real time.
Can you provide the developer name? There are many battery widgets, and those I've tried don't indicate charging level. TIA.
Click to expand...
Click to collapse
I use Battery Monitor Widget Pro by 3C. It has a history screen that shows charging current vs time. I think they have a free version.

Thanks for the tip. Battery Monitor Widget is a better monitor than those I've tried, although it overloads on detail. However I think the +/- mA reading is a net reading (charge - discharge rate) rather than the charge current by itself. Since the unit needs to be on for the widget to run, it's probably not possible for it to get just the charge reading.

+1 for the battery information widget. I actually like all of the information.
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Car charger: TF701 says "not charging"

Hi folks,
We're getting ready for a cross country trip. 2 kids, two tablets. One is a Samsung Tab 2 that charges via usb connected to a standard 12V-to-USB car charger just fine. The other tablet is an Asus TF701t. When connected to the regular USB cable for it, plugged into the 12V-to USB charger, it says "not charging." So I read up through Google and found the ASUS tabs have special requirements.
I just bought an: Asus Eee Pad Car Charger Power Adapter,36 pin 15V 1.2A Power Adapter Travel Car Charger for ASUS EeePad TF600 TF600T TF810C TF701T (Car Charger)
I plugged it in, and the tab still says "Not Charging."
Now, it IS charging a bit... despite the battery window saying not charging, I see the green timeline indicator that shows charging, and after a few minutes it went from 91% to 92%.
But I'm concerned this will be just a trickle of charging and not stand up to constant use. We've got two days of driving, 8 -10 hours per day, and this tab is my 8 year old's primary entertainment.
Given this is the official car charger for the tab, why won't it show proper charging?
My plan B is that the car does have a built-in 110V outlet. I could plug the wallwart into that (though, I need an extension cord, because the wallwart is too big to fit in the small recess where the 110V line is). I'm a bit worried the wall wart will pull too much juice through the 110V line and cause it to shut down (thermal protection).
Experiences or thoughts that might help me here?
Marc

Yeah sounds like it can't supply the correct voltage. More likely it is supplying 11V and the tab really wants 15V to charge. (Car batteries are 12V so unless it has some sort of transformer in it which is unlikely). So it will be a slower trickle charge.

Compare the car's inverter rating (the 110V outlet) with the input rating on the Asus charger. Mine wants 0.5A at anything from 100 to 240 volts, so if your car outlet is rated 120 watts or better it will do. If you are handy with a soldering iron there is a simple alternative: chop off a female USB cable and splice it into an automotive 12V power plug. Assuming your car's alternator and regulator are healthy (and of course battery) it will put out 14.0-14.5V at cruising speeds, perfect for charging Asus TFs. If your car has a 12V power outlet; many don't come with cig lighters anymore, but most have the same hole somewhere with a rubber plug in it. Word of warning though: make sure the kids don't plug the Samsung (or anything but a TF) into the modded 12V USB port, it will let the magic smoke out. They are only rated for 5V.

Turns out the car charger charged the tablet fine despite the not charging status. We started the trip at 9:30 with 75% charge. Two hours later, with constant game use, the tablet was nearly full. Stayed that way throughout the day's drive.
Thanks all.
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