yashsingh1/xdaforums huggingface dataset:
[Eee Pad Transformer Accessories] tobordeadmeat:
Thanks for the reply.

The one i found was £17 and had the following blurb (i was worried the 3.3A was too high):

In Car Charger - Perfect for Laptops, MP3 players, PDAs

Cable Length 1.7M

Voltage Outputs;

15V & 16V @ 3.3A 18V & 19V @ 2.6A 20V @ 1.5A 22V & 24V @ 1.3A

Voltage can be changed using the slide switch on the side and there is also a power on indicator.

USB Port - 5V @ 500ma (perfect for MP3 players, cameras, etc)

DC Connector Sizes;

Below are the sizes of the DC connectors and the make of laptop they are usually suitable with, this should be checked before purchasing;

External - Internal Diameter - Make of Laptop

1) 3.5mm x 1.35mm - Sharp

2) 4.0mm x 1.7mm - Gateway

3) 5.5mm x 1.7mm - Acer

4) 4.8mm x 1.7mm - HP/Compaq, Acer

5) 5.5mm x 2.5mm - ASUS, Acer, Gateway, NEC, Samsung

6) 5.5mm x 3.0mm - Toshiba, IBM, HP/Compaq, Dell, ASUS, Acer, Fujitsu, NEC Sharp

7) 6.3mm x 3.0mm - Toshiba, NEC

8) 6.0mm x 4.3mm - Sony, Fujitsu, Samsung

The power cable can be used with equipment that is centre positive or centre negative because the power adapters can be reversed by 180 degrees to change the polarity.

Other Technical Features - The charger outputs around 50 watts. If you are unsure about the power requirements of your laptop, this information can usually be found by looking at the transformer on the power cable you are currently using.

Peace of mind - This cable has been tested to CE and ROHS standards and also has overload and short circuit protection.

Connectivity - This cable has got a great range of interchangeable power adapters to increase connectivity.
[Eee Pad Transformer Accessories] Bob Smith42:
All those tips *seem* convenient, but "adapters can be reversed by 180 degrees to change the polarity" might be a BIG mistake. I found pulling apart the cables and the tip frequently comes apart from the cable. All it takes is one mistake, reverse the polarity, and the tablet is cooked. If you glue the connector to the cable it might be safe.

I am unsure if there is a charge speed limit on the tablet, such that over 1.2 amps might be too fast. Someone knowing rechargeable batteries might know the answer. The voltage of 15v is fine and will definitely work. I watch the charge rate on the graph in Dual Battery Widget to compare the original ASUS adapter to others.

Good luck.
[Eee Pad Transformer Accessories] mrg2003:
Add a diode in-line. no more cooked diode, maybe also a flashing red led,
[Eee Pad Transformer Accessories] ant_thomas:
So, for in car charging it'll charge fine as long as it's getting 12V via pin 1 and 4 on the USB connector?

Fairly sure I've got a 12V in car charger and just need to get a barrel to USB adapter then. But surely a 12V charger is just a straight through line with a fuse because the car cigarette adapter supplies 12V anyway.
[Eee Pad Transformer Accessories] newtonc:
No. My biggest concern is checking the polarity. Thanks for the help.
[Eee Pad Transformer Accessories] Bob Smith42:
Okay. I asked because I am in USA.

I have some USB A Female to 5525 Female Adapter cables that could get to you quicker than from China. Free. Your call, depending on your location. PM me if interested.
[Eee Pad Transformer Accessories] signops:
Dealextreme has this extension cable and someone posted a review that it works with the Asus Transformer.

http://www.dealextreme.com/p/usb-3-0-superspeed-male-to-female-extension-cable-180cm-length-48893
[Eee Pad Transformer Accessories] iGBH:
I've set about to make my own 12v car charger using the original asus usb3 cable (i had a spare one lying around). I've cut the standard cable and found the following inside:

foil

shielding

5 wires - red, orange, white, yellow and green.

I was expecting to find a black earth wire but there isn't. Only cables i am getting earth from is white and the shielding?

I tried connecting red to positive in accessory plug and white to earth, but it didn't start charging the tablet when plugged into 12v. On the upside, i didn't fry my transformer either. :o

Can anyone suggest how this should be wired up? In hindsight i should of just created a male usb adapter and not cut the original cable.

Thanks
[Eee Pad Transformer Accessories] Bob Smith42:
It is much safer to plug in a USB 2.0 connector to test power and signal. You do not need it connected to your tablet to test, e.g. do not do it!

Power rides the same wires in USB 2.0 and USB 3.0. You can also assume the two USB 2.0 signal lines are the same in USB 2.0 and USB 3.0 because the cable syncs with a laptop USB 2.0 port. One USB 2.0 cable will probably give you four wire colors matching +5V, ground, D+, D-.

The remaining color could be pin 7 on USB 3.0. If you have opened your cable you can test the remaining color (only) to see if it is on pin 7. Or the remaining color might be something else....

Good luck.
[Eee Pad Transformer Accessories] iGBH:
Thanks for the response.

Given my first efforts, i've changed my approach and was splicing a male/female usb extension onto a 12v accessory plug. The problem i'm having now is that each wire feed within the usb is so thin that when soldering to the plug it easily just breaks off with a little force. There is no way that this would survive any length of time in the car without falling apart. Is there a trick to this? I'm now thinking either buying a diy usb plug and soldering accessory cable directly to pins 1 and 4, or alternatively just getting a ready made option.

Ready made would be easy, but i like the challenge. :rolleyes:
[Eee Pad Transformer Accessories] Bob Smith42:
Options I would consider:

(#1) Keep ASUS 40 pin cable intact, use 75watt or higher inverter and original ASUS AC Adapter.

Advantage: Charges anything 5v or 15v safely.

Disadvantage: Clunky, lots of parts.

(#2) Get any 12V plug.

-- If it has 5.5mm barrel on cable already - tear it open and wire it direct to 12V instead of 5V. Use a female barrel to female usb adapter. Plug in the ASUS 40 pin cable.

-- If it has no cable, e.g. just a USB socket, tear it open and wire it direct to 12V.

will destroy 5V electronics, e.g. iPad, other tablets, iPhone, other phones.

-- If it has other type cable connector, find some way to install female USB socket (with 12V-15V warning) and use original ASUS 40 pin cable.

Advantage: Charges ONLY 12V-15V safely. Fewer moving parts.

Disadvantage: Warning required for ANY 5V devices because single mistake will kill devices.

(#3) Cannibalize an original 40 pin cable and remove the male USB connector and wire it directly to a 12V plug, removing internal plug components limiting to 5V and wire directly to 12V.

Advantage: Charges ONLY 12V-15V safely. Fewer moving parts.

Disadvantage: Warning required for ANY 5V devices because single mistake will kill devices. People have plugged this into a 24V truck socket and burned out the TF101.

Good luck!
[Eee Pad Transformer Accessories] iGBH:
I effectively tried #2 and #3 yesterday. The problem i'm coming up against is how thin the wires are in the usb cable. I reckon there is about 5 strands of hair size copper for + and -, so trying to solder this to anything and retain any strength without it just snapping and pulling away is beyond my ability.
[Eee Pad Transformer Accessories] johnny13oi:
I personally would NEVER wire anything directly to the 12V socket of your car. The power supplied by the car is extremely dirty and fluctuates drastically from around 13-15 Volts due to the alternator running while the car is on. I would definitely have something controlling the voltage running from the car.
[Eee Pad Transformer Accessories] RazyNyx:
I just bought this xxx.uniross.com/fr/index.php?cPath=18_44_79 and works great.

It cost 21€ in MediaMarkt.

12v x 1.5amp = 18W

I did not use the adapter 5.5mm DC Barrel Female to Female USB cable.

//dl.dropbox.com/u/2705926/Fotos/uniross1.jpg

//dl.dropbox.com/u/2705926/Fotos/uniross2.jpg

//dl.dropbox.com/u/2705926/Fotos/uniross3.jpg
[Eee Pad Transformer Accessories] fpdragon:
Good point...

I already installed my transformer in my car and I just put a 2A fuse between it. It works but sometimes the transformer has a strange behavior in detecting the power. I already posted it in a more detail here: http://xdaforums.com/showthread.php?t=1250995

Anyway... I also thought my problem could be because I have a noisy supply. I only measured with a Multimeter and the voltage seems to be stable but I can't say anything about high frequency noise. I first expected a software problem later.

Maybe filtering the supply will help?

What exactly do you recommend for filtering? I found some car filters on amazon from 5€ to 25€ but they are made for car radios to reduce hear able noise. My first thought was a linear voltage stabilizer but I know they need a input to output difference of a about 2V. That won't work if I need at least 11V+.

What would you say?

thx
[Eee Pad Transformer Accessories] iGBH:
For those looking for a neat and easy solution, i found this on ebay...

http://www.ebay.com/itm/MINI-BULET-...?pt=US_Tablet_Accessories&hash=item3a6a0cc9a3
[Eee Pad Transformer Accessories] tobordeadmeat:
Good find!

It'd be nice if someone could confirm it does actually do what it says... Not that you could ever buy something off ebay that has dodgy claims...
[Eee Pad Transformer Accessories] Bob@Desire:
Anybody tried that thing?
[Eee Pad Transformer Accessories] Bob Smith42:
One of the pictures says output 5V 1.8A instead of 12V. Another picture shows entirely different 12V 2A label. It is confusing, and hard to tell if someone modified (home-brew) a simple 5V USB car adapter and made some labels, or if this was manufactured for 12V 2A. The description says "Two USB Output Ports", and pictures all show one port. The 5V version of these cost $3 on ebay before modification.

I have a 5V version, and I opened mine up. It has a DC/DC converter, MC34063A, internally. I was surprised because it is a variable output voltage regulator. In the 5V version, R4=152 & R6=472, where Vout=1.25(R6/R4+1)=5.1V. There are some other resisters (R1-R8), three capacitors, and one diode. I might get one of these 12V versions just to compare bits.

Therefore, with some tweaking of very small parts it can be adjusted for 12V output. I will check out the circuit specs and see how easy to mod mine.
[Eee Pad Transformer Accessories] iGBH:
ive ordered one so will let you know how it goes.
[Eee Pad Transformer Accessories] clmnw:
Good find... I hope it works well. This gadget is a bit dangerous if you get carried away and hook a 5V USB device...
[Eee Pad Transformer Accessories] Beards:
Shame there's non showing on Ebay UK.

This one has a shipping charge to the UK for $14.99 Standard Int'l Shipping.
[Eee Pad Transformer Accessories] Bob Smith42:
Yeah, I looked and asked about this from a few alt suppliers. Noes, so far.

I will post the circuit diagrams for 5V, 12V and 15V versions in a few days. I have a 5V version and it seems simple. I'm getting the 12V version. I will make an attempt to design a 15V version, assuming it works to boost voltage.

I will also test, and post results - both input/output voltage & TF101 charge rate.

It is supposed to handle 24V, so any suggestions how to DIY generate 24V input for a test?
[Eee Pad Transformer Accessories] Beards:
That's very good of you.

Also. If you do come across any other sellers please do let us know.
[Eee Pad Transformer Accessories] Bob Smith42:
I surely will do. I researched the parts needed to make a 15V version, so I am just waiting for the 12V delivery to double check.

I think it will be simple, because the parts to convert one is only about $5 USD. And, we can buy quantity lots of the 5V adapter from China for under $2. The soldering job requires replacing surface mounted items, but its easy enough with the correct tools.

This is going to be a project, for sure.... :)
[Eee Pad Transformer Accessories] Beards:
And one which I will enjoy following. :)
[Eee Pad Transformer Accessories] retali8:
Does anyone know where else besides eBay to get the USB barrel plug? I ordered it off eBay but the seller responded with "they adjusted the export policy and stopped many goods for inspection.

And it is really affected delivery much. Really sorry for inconvenience.

how about wait 3days again ,if still not be received after 3days ,please feel free contact us ,we promise give you full refund ,ok ?"

It's been several weeks now and still shows that it hasn't been received by USPS. :(

Damn China. :mad:
[Eee Pad Transformer Accessories] tobordeadmeat:
Working car solution

Okay, Iv'e got a working solution for the car that doesn't involve soldering and isn't too expensive (but is still about £10 more than we should really have to pay!).

Got :

"USB A Female to 5525 Plug Female USB 5V Power Adapter" from ebay for £2.99

"Ring Automotive RMS11 Multi Voltage Adaptor with USB Port" from amazon for £12.99.

It works fine and didn't blow up when the polarity was round the wrong way... phew!

The adaptor is alot but you can always use it for other poweer hungry things.
[Eee Pad Transformer Accessories] Bob Smith42:
Which country?
[Eee Pad Transformer Accessories] Bob Smith42:
In a word? SCAM.

I tested the output voltage, instead of 12V the output of this item is 2.8V. Worthless?

I recommend if you did buy this - please post your results (especially if you have a multimeter). If you did not buy it - YOU WIN! ;)

Internally the DC DC converter part number (a5268 am16ai) does not match anything via Google nor Digikey. It is uniquely designed, and quite different components and layout than 5V mini bullet chargers.

====

UPDATE:

If you are going to steal money from people why limit your scam to ebay? Amazon is also available for scamming.

What is AMAZING is some people are giving 5 star reviews of other 5V car chargers for the ASUS TF101. Using 5V to charge a device requiring 15V should surprise anyone with half a brain. What is always lacking is the 5V charging rate (in use and off) of the TF tablet. Why can't some excited user of a 5V charger post a charging rate graph from Dual Battery Widget? Come on, its easy, right?
[Eee Pad Transformer Accessories] Beards:
Interesting.... I have raised a question with this supplier on Amazon UK.

It is advertised to work with the TF but when you look at the technical details you have to question it's claim.

I've contacted both Amazon and the supplier. Amazon got back to me and want me to keep them informed. The supplier however is not responding at the moment....
[Eee Pad Transformer Accessories] Bob Smith42:
Beards, you might be wasting your time. I have done similar queries with many, many companies. It goes back before the TF, just as the higher amperage car adapters were becoming popular and the Galaxy Tab 7 inch needed extra power. The GT7 has a uniquely proprietary charging system, too. There are likely 100's of fakers in the marketplace.

The bottom line is almost 100% the 3rd party distributors I contacted were making false claims about supporting various tablets. The only factual results I ever obtained was from one company making a special charger, or from other users conducting reviews, and including all the technical details.

When something looking unique comes along, like the 12V bullet charger, I might check it out quickly, but usually I just ignore all the false claims (lately).

Good luck.
[Eee Pad Transformer Accessories] Beards:
Yes, I do agree with you on what you say. I had a Galaxy 7 and fell foul to a few incorrect chargers.

However, if I can challenge just one false claim it's one less that is getting away with it.

I'm hoping as this one has the backing of Amazon I can get them to remove the sellers claim but more importantly my belief is if you make them aware this is happening sometimes just sometimes it spurts a brief drive to look at other sellers info.

Fingers crossed.....
[Eee Pad Transformer Accessories] retali8:
I'm in the USA. I just checked the tracking information the seller gave me again and it shows that USPS still has not received the item so I contacted the seller again asking if it could be shipped through another carrier because I can't seem to find this barrel plug anywhere else but eBay. Maybe someone else on here ordered extra's that they could sell me? :P I just need one! Ugh... :mad:
[Eee Pad Transformer Accessories] Bob Smith42:
Send me a PM. :)
[Eee Pad Transformer Accessories] Bob Smith42:
I got mine in ~17 calendar days, China to USA, but some stuff I ordered from took over 20 and up to 30 calendar days. In a few cases, they never arrived, so it is a gamble.
[Eee Pad Transformer Accessories] eephyne:
i don't know if anyone has already got that , but i just found out this morning why (for my plug) it's stop charging, it's because the cable weight push the plug (dock side) down .

When i push the cable up and pull the plug upside , it's chargin again , does anybody else have the same result ?

(sorry for my english btw)
[Eee Pad Transformer Accessories] azizmulhim:
Can someone help grok where I can get female usb with polarity at the end like the head of asus charger.
[Eee Pad Transformer Accessories] Bob Smith42:
Do you mean like this?

USB A Female to 5525 Plug Female USB 5V Power Adapter
[Eee Pad Transformer Accessories] azizmulhim:
No barrel put two pins for polarity as in the previous picture.
[Eee Pad Transformer Accessories] Bob Smith42:
Okay, right. The closest I have seen comes with this (female USB is item *left* of thing labelled "fc"):

Dynex Universal AC/DC Charger Cameras Camcorders DX-UA

But, look closely, the two pins are different width - forcing polarity. And, the pins do not have a cover like your picture.

Good luck.
[Eee Pad Transformer Accessories] kalkrishnan:
Bad product, good ebay seller

This does seem to be a false claim. I received mine and plugged it in to test. The thing visibly put out some smoke and my car was smelling horrible. The light on it would not turn on. I quickly unplugged it, and emailed the seller.

The seller sent me another one free of charge. This one did not burn up (thank goodness), but is not charging the TF either. I suspect the voltage is too low. I have not taken a meter to it, will probably do that sometime when I get the time. I emailed the seller again, and the seller issued me a quick and courteous refund, no need to ship the units back. So, I would say, don't buy it!
[Eee Pad Transformer Accessories] Rittberg:
Positive or negative polarity ?

Hi,

In order to use a Wall charger, what should be the 12V – 15V output polarity(the output polarity where the 5.5mm DC Female Barrel to USB Female cable is going to be connected) ?

Positive or negative polarity ?

Thanks.
[Eee Pad Transformer Accessories] Bob Smith42:
Normal, center pin positive polarity. :)
[Eee Pad Transformer Accessories] iGBH:
I received mine yesterday and have had mixed results. I have managed to see it visibly charge the TF once with the screen on. It said charging via AC so was working as it should. I've also tested pins, and without load it only shows 2.8v as per Bob's findings.

However, since then i have not been able to get it to charge at a high voltage rate again. It has been charging with the screen off (and reasonably quickly ie 5% in 15mins - not sure how this compares to mains AC?) I've also had it plugged in with the screen on and using GPS. The battery level is not decreasing, but it is not increasing either. It does not indicate that it is charging.

It seems there are certain scenarios where this bullet plug does work, although i haven't managed to narrow down the exact conditions. I believe it needs to have pretty high direct voltage (ie does not work with accessories on, but does work with motor running), and the current draw also seems to influence it (ie screen on or off).

It has a blue charging indication light on it. With the screen on, it is a dim blue. Turn the screen off, and it lights up brightly to indicate (i assume) that its charging.

I've just installed dual battery widget to monitor battery charging so will let you know when i know more.
[Eee Pad Transformer Accessories] Bob Smith42:
I am going to test mine again. I am suspect of the 2.8V output into a meter.

I will add probes so I can measure volts while charging, and track a couple hour charge using Dual Battery Widget.

If it was easier to find specs on the DC DC IC chip at least we could check the design. Hmmm.... I still suspect scam, but I could be wrong.
[Eee Pad Transformer Accessories] iGBH:
A further update following my drive home tonight with the transformer plugged in.

In my vehicle i have a dual battery system and i have access to 12v accessory plugs in the front of the vehicle that are from both the main and auxiliary batteries.

Unfortunately i didn't have my multimeter with me but i narrowed down the circumstances where this charger seems to work.

1) Main battery 12.9v+ - plug in with screen on = no charge. Blue light on charger remains dim.

2) Main battery 12.9v+ - plug in with screen off = maintenance charge (ie does not drop battery capacity with screen on and gps operating.) Does not increase charge though. Blue light is bright, but transformer does not indicate charging.

3) Main battery 12.9v+ - plug in with transformer switched off = full charging power even when tablet boots up. Blue light on charger bright, and tablet says charging via AC.

From the above testing, it would seem the charger measures the load or power draw at the time of plugging in and alters the voltage it sends depending on this. I'm not sure if this is a design feature or a side effect of poor design?

Repeating the above on the auxiliary battery which would be around 12.4v was less successful. It would charge with screen off, however would not when the screen was turned back on. And my test with plugging it in with the transformer turned off did not work as above - it did not indicate charging.

So from this round of testing it would seem that:

1) how much voltage it pumps out (and therefore the type, if any, of charging that takes place) is dependent on current draw when first plugged in; and

2) it is sensitive to input voltages. 12.4v may not be enough for this to work adequately and it may require 12.9v+ to work reliably.
[Eee Pad Transformer Accessories] aquamally:
USB 3.0

I purchased a USB 3.0 extension for my Transformer. It didn't work for some reason. Don't know if it's the cable? Here is the link incase anyone else is going to try.

http://www.ebay.co.uk/itm/200642498172?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
[Eee Pad Transformer Accessories] browngeek:
mobile charger pack 5200mAh

http://www.beecrazy.hk/hong-kong/deal/$188-for-a-5200mah-mobile-charger,-perfect-for-short-trips,-ac-adapter-fits-iphone,-htc,-nokia,-moto

The above is an offer with one of the group buying sites in Hong Kong.

The charger pack is supposed to support 5200mah.

Reckon it will work with the transformer?
[Eee Pad Transformer Accessories] wethead4:
I got the one from Monoprice.com and works like a charm. usb 3.0 extension.