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2012 Nexus 7 Discussion Forums (1st Generation) => Nexus 7 Accessories => Topic started by: birdastrompgman on July 01, 2012, 10:43:54 AM

Title: Car charger?
Post by: birdastrompgman on July 01, 2012, 10:43:54 AM
Will any micro USB charger work?  I mixed up a Tom-Tom GPS charger with a Garmin GPS, or v.v., and kept putting the GPS in hibernation.  What will the Nexus 7 require to charge it while driving?  I gather it will ship with an AC charger and a cable.
Title: Re: Car charger?
Post by: Drew on July 01, 2012, 12:56:38 PM
Yes, it will come with a USB charger and a USB to micro-USB cable.  If you have a car adapter that is USB, check the voltage to see if it matches the Nexus 7 specs.  If you are not familiar with AC/DC voltage and ratings, just buy a Nexus 7 car charger on Amazon, EBay, etc. You don't want to under/over charge your new tab and ruin the battery. 

They should be available pretty soon as after-market retailers will have any and every thing you'll need for this tablet.
Title: Re: Car charger?
Post by: comiskeybum on July 14, 2012, 07:02:02 PM
Where does one find the voltage.  I have a verizon/motorola car charger.  Motorola car chargers are pretty good with one exception, dont use it with Samsung devices. 
Title: Re: Car charger?
Post by: edhunter on July 14, 2012, 08:11:06 PM
I'm hoping that it will charge in my car/van. I had an ipad 3 and it wouldn't charge which I assumed was due to the size of the battery required to power the retina display (which is massive). Due to the size of the Nexus 7 in comparison,  I think it should be fine with most micro usb chargers.
Title: Re: Car charger?
Post by: Drew on July 14, 2012, 08:27:11 PM
Where does one find the voltage.  I have a verizon/motorola car charger.  Motorola car chargers are pretty good with one exception, dont use it with Samsung devices.

Usually it is printed on the side as part of the plastic or sometimes a label.

I'm weird about chargers and their output matching the device to be charged, but I guess a cell phone charger would work in a pinch....but don't blame me if it blows up.  :o
Title: Re: Car charger?
Post by: bjohns007 on July 18, 2012, 02:40:59 PM
The provided charger is 5v DC @ 2 amps. Most car chargers will do 5v @ 1 amp, which should power up the device and charge slowly.

There may be some car chargers that will provide 2a (IPAD3 / Samsung Galaxy tab chargers?) .. but those are the specs .. good luck!
Title: Re: Car charger?
Post by: samalex on July 18, 2012, 03:37:35 PM
I'm using the same charger both in the house and car that came with my DroidX, and it's working.  I just figured the USB charging standards were the same across all devices, and whether the DroidX or even our Kindle Fire charger all seem to work fine with the N7. 

Title: Re: Car charger?
Post by: edhunter on July 20, 2012, 03:31:17 PM
I've definitely noticed a few difference between different chargers with the speed which they charge compared to the one that came with the device. I'm going to look to buy a few more 2a chargers
Title: Re: Car charger?
Post by: comiskeybum on July 20, 2012, 03:33:59 PM
As long as its a 5V charger, which 99% of micro usb chargers are, you're fine.  However, if its only pulling less than 1A it will take forever to charge.  Its best to purchase one that pulls at least 1.5A. 

The thing that frustrates me is that the two verizon car chargers i have now do not have the specs listed on them ANYWHERE. 
Title: Re: Car charger?
Post by: radiocycle on July 22, 2012, 01:18:05 PM
As long as its a 5V charger, which 99% of micro usb chargers are, you're fine.  However, if its only pulling less than 1A it will take forever to charge.  Its best to purchase one that pulls at least 1.5A. 

The thing that frustrates me is that the two verizon car chargers i have now do not have the specs listed on them ANYWHERE.

Well... it's actually your device, that does the *pulling*.

r
Title: Re: Car charger?
Post by: mscroggi on July 23, 2012, 07:48:44 PM
Yes, it will come with a USB charger and a USB to micro-USB cable.  If you have a car adapter that is USB, check the voltage to see if it matches the Nexus 7 specs.  If you are not familiar with AC/DC voltage and ratings, just buy a Nexus 7 car charger on Amazon, EBay, etc. You don't want to under/over charge your new tab and ruin the battery. 

They should be available pretty soon as after-market retailers will have any and every thing you'll need for this tablet.

Ugh....  its USB!  The voltages are going to be what the USB spec designates...   You're not concerned with voltages..   What you are concerned with is current (amps) .   The OEM charger for the Nexus 7 is 2 amps.   Your goal would be to get a USB outlet in your car that can deliver 2 amps.   Like the others have said, 1A should be a minimum.   The more you can get the better.   It will likely work on lower amperage models, but it will charge very slowly.. and your charger will likely get hot.     
Title: Re: Car charger?
Post by: Trankster on July 24, 2012, 07:52:53 AM
Used my Verizon my car charger  (for HTC DINC2) yesterday. In less than an hour charged from 78% to 94% without any problems.
Title: Re: Car charger?
Post by: paj on August 30, 2012, 10:09:55 PM
I have three USB car adapters. Two are rated at 2.1A and the other at 700mA.  All three charge fine when the N7 is off.  None will charge when the N7 is on.  Loosing hope that this tablet can be used in the car....
Title: Re: Car charger?
Post by: GreyGhost on September 03, 2012, 08:49:55 PM
Hi, new to the forum ...
Has anyone tried AC/DC converter with outlet ?

http://www.amazon.com/Charger-Inverter-Adapter-Converter-Outlet/dp/B008H1G3UA%3FSubscriptionId%3DAKIAJH6GPQMUOJBOMWHQ%26tag%3Dnewephedradietpills-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D165953%26creativeASIN%3DB008H1G3UA (http://www.amazon.com/Charger-Inverter-Adapter-Converter-Outlet/dp/B008H1G3UA%3FSubscriptionId%3DAKIAJH6GPQMUOJBOMWHQ%26tag%3Dnewephedradietpills-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D165953%26creativeASIN%3DB008H1G3UA)

I've been considering this route for charging and using as a GPS in the vehicle ...


-Gregg
Title: Re: Car charger?
Post by: birdastrompgman on September 03, 2012, 10:20:57 PM
No, but let us know if it works, GreyGhost.

I've posted the following Amazon.com DC charger review (http://www.amazon.com/gp/product/B00622AG6S/ref=oh_details_o03_s00_i01) in two other DC charger threads, but didn't do it in my own thread (until now).  Apparently most 2.1A DC USB chargers output a total of 2.1A, and will provide 2.1A to an iPhone or iPad, but will only output .5A to most other devices.  See the explanation below.  I can't say whether the reviewer's claim is true or not, but it sounds plausible.

There is apparently a workaround to get these 2A-2.1A USB chargers to give 2A to our N7s.  It involves buying a USB extension cable (male USB connector on one end, female USB connector on the other end), cutting it open, and  soldering the green and white data wires from the tablet/phone end. (http://forum.xda-developers.com/showthread.php?t=1791717/)  I haven't tried this yet, but I'll try it tomorrow, and post a DIY if I'm successful.
-------------------------------------------------------------------
This product has two major issues:

1. While it's description claims it has a 2 Amp port and a 1 Amp port, the reality is that it has bridged the two ports and it can only source 2 Amps total. It is not capable of delivering 3 Amps combined like the description implicitly claims and could never simultaneously charge an iPad and a smart phone. (UPDATE: The technical details section now indicates more clearly the 2A total, which is appreciated.)

2. The 2 Amp port appears to be using the Apple protocol for USB power, so that port will only provide 0.5 Amps to most other devices.

The upside of this is the 1 Amp port somewhat over delivers, and can source 2 Amps if nothing else is connected and 1.5 Amps if the 2 Amp port is sourcing 0.5 Amps for a non-Apple device. Thus this product can support one-high power non-Apple device (in the 1 Amp port) and one lower power device (in the 2 Amp port).

Now some more background/details...

First, a little background on USB charging for those who don't know:

The USB power spec is for 0.5 Amps at 5 Volts... or 2.5 Watts. This was great up until the last couple years when devices have gotten really power hungry, particularly smartphones and tablets and to a lesser extent dedicated GPS's. Some of these devices use over 2 Amps, particularly the tablets like the iPad (or in my case the HP Touchpad).

Manufacturers of these devices therefore had a dilemma. If they had their devices pull more than 0.5 Amps, they risked damaging the power source, which could be a computer, that was only prepared to source 0.5 Amps. Thus the manufacturers have used tricks to determine whether their device is connected to an unknown source, at which point they purposely only draw 0.5 Amps, or to the dedicated charger that was provided with the device, where they can draw all the power they need.

There seem to be two common tricks used. The first is to short the two data-wires together in the charger. This is what most non-Apple devices do. Since a computer or older device wouldn't have done this, the device can assume it is safe to draw all the power it needs.

Apple seems to have taken a different approach, one that I don't fully understand but know can be seen by the fact that the data lines are neither open nor shorted when the charger is plugged in, and is more sophisticated and probably superior, because I suspect it allows the device to know exactly how much power it can use.

While Apple taking a better approach might be nice in concept, it's created chaos in the USB charger product category. What is the non-specific charger to do? They can't support both.

This device chose to go the Apple route for the 2 Amp port. I don't own any high-power Apple devices, so I can't say for sure, but I suspect this unit performs well with Apple devices. Using electronic equipment I was able to draw 2 Amps when putting a fixed load on this USB charging port. However, when I connect any of the 3 high-power devices I have (HP Touchpad (2 Amps), Motorola Triumph Android phone (0.85 Amps) and the LG Optimus Slider (0.7 Amps)), none of them drew all the current they could have, because they were expecting a shorted set of data-lines.

Luckily for my purposes, the 1 Amp port on this device uses the data-line shorting method. As such, it was able to deliver all the power my Triumph and Optimus wanted. However, for some reason, even when it was the only device connected, it would not fully charge the HP Touchpad at the 2 Amps it could have, because for one reason or another, the HP Touchpad rejected it as a high power charger.

To be honest, this surprised me because it was able to source the 2 Amps the Touchpad claims it needs and the HP Touchpad charger has the data-lines shorted. So I'm not sure why this didn't work.

Thus this device gets 3 stars (UDPATE: 4 stars) because it can source the current it claims (minus the somewhat deceptive 2A + 1A notation (UPDATE: Which is now more clear in the technical details)), would likely support an iPad like it claims, but falls short in other regards noted elsewhere.

For non-Apple users, or even more so mixed users (say an iPad and an Android phone?) this device is superior to the other device I purchased, the "Kensington K33497US PowerBolt Duo Car Charger" (http://www.amazon.com/gp/product/B003PU01M4/ref=oh_o02_s00_i00_details (http://www.amazon.com/gp/product/B003PU01M4/ref=oh_o02_s00_i00_details)) because on that device, NEITHER port works with non-Apple devices (although it performed better power-wise, see my review over there for details).

I've ordered two additional devices:
- "Ultra Compact High Output Dual USB Car Charger - 2.1A Output" (http://www.amazon.com/gp/product/B00470C35E/ref=oh_o01_s00_i00_details (http://www.amazon.com/gp/product/B00470C35E/ref=oh_o01_s00_i00_details))
- "Bracketron Universal Dual USB Car Adapter (UGC-298-BL)" (http://www.amazon.com/gp/product/B0056VNVV8/ref=oh_o00_s00_i00_details (http://www.amazon.com/gp/product/B0056VNVV8/ref=oh_o00_s00_i00_details))

Hopefully one of the two of them will be able to deliver to their specs for my devices.

UPDATE: I've increased my review to 4 stars for two reasons:

1. The changed technical details text makes it more clear its total power capacity.
2. Of the 4 models I purchased, it's one of the two I kept and it's the only one I kept in unmodified form. That's got to count for something. :)
Title: Re: Car charger?
Post by: ecd1211 on September 06, 2012, 04:39:58 PM
After trying several car chargers, I finally found one that works with my N7. This is the link from Amazon:

http://www.amazon.com/gp/product/B008MS9XA0 (http://www.amazon.com/gp/product/B008MS9XA0)

And it's less than three bucks -- I wasn't expecting much for the price, but it works and it seems to be pretty well built for the price.

*** UPDATE ***

I guess I need to rescind my recommendation of this charger. It appears to be just a trickle charger for the N7 -- today, for example, my battery was at 70 percent when I started my commute -- the battery icon indicated that it was charging, but at the end of my 40 minute commute, the battery was at 67 percent.

It's really frustrating that fully-functional chargers and cables are so hard to find for this device. As someone who also owns an iPad 2, I'm a little mystified as to why the Nexus 7 seems to have standardized connectors, but doesn't support a majority of accessories...
Title: Re: Car charger?
Post by: birdastrompgman on September 09, 2012, 10:24:49 PM
The extension cable rewire mod worked.  It allowed me to charge my N7 with a car charger that didn't work using just the OEM cable.  Here's my DIY writeup. (http://nexus7forum.com/index.php?topic=890.0)
Title: Re: Car charger?
Post by: GreyGhost on September 12, 2012, 08:56:48 AM
Hello again Folks ...

I can report that this charger does indeed work using the AC outlet in conjunction with the Nexus 7 native charger ...

http://www.amazon.com/gp/product/B003Q54V88/ref=oh_details_o00_s00_i00
 (http://www.amazon.com/gp/product/B003Q54V88/ref=oh_details_o00_s00_i00)
Strangely, the onboard 2.1V USB outlet does not work though ...

HTH ...

I report more as I get some use in with it ...


-Gregg

Title: Re: Car charger?
Post by: birdastrompgman on September 12, 2012, 06:32:52 PM
I can report that my modded usb extension cable & iPhone - compatible car charger brought my Nexus 7 up from 75% charge to 100% during an 8 hour drive while the n7 was powered down. .

Yesterday, however, it failed to keep up with the Torque app, and I ended up with a 0% charge after an 8 hour drive with Torque running & plugged into the car charger.
Title: Re: Car charger?
Post by: GreyGhost on September 23, 2012, 07:31:56 AM
Hello again Folks ...

I can report that this charger does indeed work using the AC outlet in conjunction with the Nexus 7 native charger ...

[url]http://www.amazon.com/gp/product/B003Q54V88/ref=oh_details_o00_s00_i00[/url]
 ([url]http://www.amazon.com/gp/product/B003Q54V88/ref=oh_details_o00_s00_i00[/url])
Strangely, the onboard 2.1V USB outlet does not work though ...

HTH ...

I report more as I get some use in with it ...


-Gregg


Well, I've now used this charger on a day road trip and it worked like a champ keeping the Nexus 7 at 100% all day long with the GPS Navigation running ... Even some games were played and it was able to get the Nexus 7 back up to 100% quickly after being plugged back in ...


-Gregg
Title: Re: Car charger?
Post by: radiocycle on September 23, 2012, 11:14:53 AM
Hey, cool lookin' charger Gregg, thanks!

radio
Title: Re: Car charger?
Post by: paulie7880 on September 28, 2012, 04:29:01 PM
So Bird,
I'm not certain which supply you gave the 5 stars to?

I am a new Nexus 7 user and wanted to (like the other user, charge in the car while using it as a GPS.

Thanks for you effort and imput.  I can tell a lot of thought and research went into it.
Title: Re: Car charger?
Post by: birdastrompgman on October 01, 2012, 12:18:35 AM
The DIY cable mod should work with any iPhone-compatible USB 2A-2.1A charger
Title: Re: Car charger?
Post by: ried16 on October 15, 2012, 12:42:37 PM
ive tried 2 different car chargers with the oem cable with no luck. they were both  dual chargers that stated they delivered 2.1 amps if one port was used the other 3 amps using one port. are they lying and i need a single port charger with 2 amps or better?
Title: Re: Car charger?
Post by: birdastrompgman on October 15, 2012, 01:01:53 PM
Read the last post on page 1 of this thread.  It explains why most 2 and 2.1 amp chargers don't work with our Nexus 7s.  They only supply 2A to iPhones and iPads, while supplying the USB standard 0.5A to other devices.  See my link to my DIY cable mod near the top of page 2 of this thread for a workaround.