[Q] Old Nokia Charger for Defy - Defy Q&A, Help & Troubleshooting

Hello Defyers
I have an Old (small pin) nokia car charger its specs as the following
- Input 12v DC
- output 5.7 V 890 mA
I want to convert this small pin charger to a micro USB by some cutting and wiring
My concern is... if i use this charger with my Defy will i fry it...
its standard charger produced 5V , 850mA
with that 0.7V difference i might overload my circuts but it will work in the end
or i will end up with a black shiny brick
my defy is over clocked and running CM7

I've been using this adapter for a while (got it with the E52 from work). Donn't know about rewiring (might be hard to find a "blank" microUSB jack).
Cheers!

use 5 volt regulator IC in output voltage..

Use a diode in forward bais it give .7 voltage drop across it ...
Sent from my MB526 using xda app-developers app

USB specs allow for a 10% voltage tolerance and that's a conservative safety margin. If your 5.7V charger really spits out 5.7V (and not 5.7 + 10%) you have nothing to worry about.

detailes
rogier666 said:
USB specs allow for a 10% voltage tolerance and that's a conservative safety margin. If your 5.7V charger really spits out 5.7V (and not 5.7 + 10%) you have nothing to worry about.
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Click to collapse
you must strip the wires, cut the white and green and put them together, black and red leave them as they are, i have an 2000mAh charger built from a router adaptor and it is working very good, and that i have solved the problem with auto charger that is not OEM- Motorola.

Related

Power adaptors

Anyone seen where to buy extra power adapters? Be nice to have one with a longer cable. Stock one is very short.
Wish it was USB charged....
Sent from my Nexus One using XDA Premium App
http://www.androidtablets.net/forum/acer-iconia-tab-a500-forum/13840-chargers.html
Found another forum discussing the lame power cable.
Sent from my Nexus One using XDA Premium App
I couldn't stand it anymore so I snipped my wire and added another 4 ft.
I have been trying to get an additional PSU and car charger for my Acer. Went to Frys, tried almost EVERYTHING they have on those Universal PSU and NONE of them work in the pin connector for the Acer. What gives!
Try to get a free tip for my Energizer Xpal and also result in zero search. Any fellows have a pointer to where in getting the right tip? Thx
So far the ONLY one that I have found that works is the Enercell 12 / 1.5 with the 'G' tip, but it's like $30 at RadioShack. The tip itself is a little long and if it wiggles it will stop/start charging off and on.
I'm working with a few people to find some at decent price for us.
anyone measured the dimensions of the charging tip at all? If worse comes to worse we could always buy a generic 12v 1.5a AC adapter from ebay and buy the tip separately to solder on.
The USB port wont be able to charge the tablet fast enough and the battery will still drain. I've found that this happens on my Xperia X10 mobile phone. I have to disable 3G data in order get it to start charging.
julz said:
anyone measured the dimensions of the charging tip at all? If worse comes to worse we could always buy a generic 12v 1.5a AC adapter from ebay and buy the tip separately to solder on.
The USB port wont be able to charge the tablet fast enough and the battery will still drain. I've found that this happens on my Xperia X10 mobile phone. I have to disable 3G data in order get it to start charging.
Click to expand...
Click to collapse
The 'g' tip for the Encercell is 1.1mm x 3.0mm
Hope that helps
thanks for hte dimensions... unfortunately they don't sell that brand over here in Australia. I'm also reluctant to pay ~$30 for a charger.
I wonder if one of the round tips on this USB charger would fit:
http://www.dealextreme.com/p/10-in-1-usb-powered-charging-cable-for-ipod-psp-cell-phones-34674
It may still charge if the device is switched off completely.
atomicwedgie said:
I couldn't stand it anymore so I snipped my wire and added another 4 ft.
Click to expand...
Click to collapse
Yeah nice one, I was thinking of doing the very same thing as it should not cause any problems.
So did it go ok, what did you use for the extra wire?
________________________________________________________________________
ZTE Blade - Rooted OC 729mh - CM7 RC2 V/nice
Advent Vega - Rooted OC 1.4gh - Corvous5 rom gorgeous smooth and qqqick
Iconia A500 - Rooted - HComb Sweet
I can confirm the Radio Shack Enercell (12vdc, 1.5a) with the 'G' tip works. Picked one up today for $29 (get the tip for free) and its currently charging the Acer as I type this.
Tip: http://www.radioshack.com/product/index.jsp?productId=3807935
Plug: http://www.radioshack.com/product/index.jsp?productId=3807944&numProdsPerPage=60
MJ-12 said:
Yeah nice one, I was thinking of doing the very same thing as it should not cause any problems.
So did it go ok, what did you use for the extra wire?
)
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No charging difference at all except I don't have to have my face mashed up against the wall while it charges.
I used a piece of wire from an old 1amp charger I had. The extra piece doesn't even get slighty warm. 1.5 amps isn't all that much juice. I did solder the connetions too.
huh and it is only $10 for a new one.
http://us-store.acer.com/product.aspx?pn=LC.ADT0A.024
atomicwedgie said:
huh and it is only $10 for a new one.
http://us-store.acer.com/product.aspx?pn=LC.ADT0A.024
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Click to collapse
Even at $10 it is grossly overpriced
Acer needs to offer a PS with a six foot cable that is not crazy thin like the stock PS.
rushless said:
Even at $10 it is grossly overpriced
Acer needs to offer a PS with a six foot cable that is not crazy thin like the stock PS.
Click to expand...
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True story
Did a quick google on my powersupply PSA18R-120P.
Came up with http://pdf1.alldatasheet.com/datasheet-pdf/view/284284/PHIHONG/PSA18R-120P.html
or
http://www.phihongusa.com/html/pr_psa18r-120p.html
"The PSA18R-120P is priced at $10.23 per unit at OEM quantities"
Assuming they bought off the shelf:
DC Output Connector
2.1x5.5mm Center Positive Standard
For us australians: Going to see if I can visit Jaycar and will report back in with what I find.
Wal-Mart Car Charger
The Wal-Mart Car charger for portable DVD players works perfect.
a quick look at the wall power supply says that it it needs 12V at 1.5 amps with center of tip positive.
The Wal-Mart car charger puts out 2000ma (2amps), and has a tip that works.. It works PERFECT and it only costs 15 bux.
usb charging is out.. usb is only 5V at 500 ma (.5 amp).. not sure why everybody complains about wanting USB to charge their tablet. Even if they did add it, it would take so terribly long to charge it, you would get mad. With the proper charger and voltage, it only takes about 2-3 hours to fully charge the thing...
Good luck!
mikldom said:
The Wal-Mart Car charger for portable DVD players works perfect.
a quick look at the wall power supply says that it it needs 12V at 1.5 amps with center of tip positive.
The Wal-Mart car charger puts out 2000ma (2amps), and has a tip that works.. It works PERFECT and it only costs 15 bux.
usb charging is out.. usb is only 5V at 500 ma (.5 amp).. not sure why everybody complains about wanting USB to charge their tablet. Even if they did add it, it would take so terribly long to charge it, you would get mad. With the proper charger and voltage, it only takes about 2-3 hours to fully charge the thing...
Good luck!
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This has been a topic of discussions for a LONG time hopefully you'll know.... Couldn't there be a potential issue with charging at 2 amps when it calls for 1.5?? I was told you could use less but not ore without causing damage to the battery?
I have a 'demo' on the way from overseas to try that I should get Wednesday. I will let you know ASAP.
This is a big issue with me as I prefer a charger at home and the office and I'd like something that I can charge on my desk 'without my face mashed up against the wall' (as atomicwedgie so perfectly put it)
it2steve said:
This has been a topic of discussions for a LONG time hopefully you'll know.... Couldn't there be a potential issue with charging at 2 amps when it calls for 1.5?? I was told you could use less but not ore without causing damage to the battery?
I have a 'demo' on the way from overseas to try that I should get Wednesday. I will let you know ASAP.
This is a big issue with me as I prefer a charger at home and the office and I'd like something that I can charge on my desk 'without my face mashed up against the wall' (as atomicwedgie so perfectly put it)
Click to expand...
Click to collapse
The Amp rating on wall chargers is what the charger is CAPABLE of outputting, not what it is always outputting. As long as there is current limiting built into the charging circuit (which is a must), then the charging circuit in the A500 won't pull any more amperage than it needs to charge. Don't worry about buying a higher amperage charger than is needed, but do worry about buying one that is lower as it can overload the charger.
silic0re said:
The Amp rating on wall chargers is what the charger is CAPABLE of outputting, not what it is always outputting. As long as there is current limiting built into the charging circuit (which is a must), then the charging circuit in the A500 won't pull any more amperage than it needs to charge. Don't worry about buying a higher amperage charger than is needed, but do worry about buying one that is lower as it can overload the charger.
Click to expand...
Click to collapse
Absolutely correct.
silic0re said:
The Amp rating on wall chargers is what the charger is CAPABLE of outputting, not what it is always outputting. As long as there is current limiting built into the charging circuit (which is a must), then the charging circuit in the A500 won't pull any more amperage than it needs to charge. Don't worry about buying a higher amperage charger than is needed, but do worry about buying one that is lower as it can overload the charger.
Click to expand...
Click to collapse
Yes... pulling too much amperage is a very bad thing.

Power Cord...

Well, I'll need to ask this question: do any of you guys know if Acer is going to bless us with a USB to proprietary connector for our Iconias?
Look, I've accepted the length of the power cord. One, it is what it is and two I can always go and buy an after market adapter which could be longer. Fine. What is unforgivable, to me, is that I need an AC plug and I can't use the myriad (at least three) AC to USB plugs that I have to charge my unit. Heck, I can even use my wife's iPad adapter to charge my EVO in a pinch.
It can be done as I assume that the docking station Acer sells can charge the unit. Besides if Sammy, Toshiba and Asus have similar things why can't Acer? If they come up with something like this they'll (to me) boost the value of my Iconia a bit: I can use USB and the other adapter to charge it.
C'mon Acer: get in gear!
I'm not 100% sure I understand the question, but I'll take a stab anyway.
It is impossible to charge through USB to the A500, either through the USB ports or the dock connector. USB only has a 5v signal on it, and I believe it's max current capacity is 500ma (per standard), whereas the A500 needs 12v and 1.5a of current.
Does that help?
USB 2.0 standard allows maximum output of 1.5 amperes, or 1.8 amps on a dedicated charge port with a special cable (e.g. cannot carry data but can only charge, I have never seen one by the way) at 5 volts. These 1.5 and 1.8 amps are for USB chargers by the way, computer USB 2 ports are all rated to a max. of 0.5 amps.
A500 needs 1.5 amps at 12 volts, which is roughly 2 times more current than the usb standard (Watts = Voltage x Amps), e.g. acer power brick supplies 18 watts vs a dedicated USB charger can only supply 9 watts at 1.5 amps. Most of the phone chargers that use USB cables are around 1 amp, making their max. output 5 watts vs 18 that acer needs.
In summary, it is not possible to charge A500 via USB.
No, no, no....
I think I explained myself poorly.
You guys know that the on the bottom of the Iconia there's a connector; a proprietary connector. I assume that the unit can be recharged through there. So what I was saying is that there should be a cable that ends in that proprietary connector on one side, and on the other on a standard USB connector so that it can be charged. Very much like the iPad or the Samsung Galaxy.
I should have mentioned the word 'proprietary'
citizenklaw said:
I think I explained myself poorly.
You guys know that the on the bottom of the Iconia there's a connector; a proprietary connector. I assume that the unit can be recharged through there. So what I was saying is that there should be a cable that ends in that proprietary connector on one side, and on the other on a standard USB connector so that it can be charged. Very much like the iPad or the Samsung Galaxy.
I should have mentioned the word 'proprietary'
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If I had read your original post carefully I would have noticed that
That would work if they made a 5 volt, 4 amp charger with removable usb cable on the charger end as you suggested, and we would be able to use that charger for everything else as well.
Well...
I'm keeping my fingers crossed.
Not to rain on your wishing parade, but it wouldn't work, even with the dock connector adapter. The batteries in these tablets are 7.3 volt Li-Po packs(I think thats the voltage at least) so they require at least 9 volts to charge them. Thats why the docks that Acer makes for these use the same power supply as the tablets themselves. Without high enough voltage, it wouldn't charge. I guess you could make a charger that would plug into the connector on the bottom, but you would end up having to use the same old power supply to get it to do anything. Conceivably you could make a double USB plug on the other end wired in series, that would bump it to 10 volts/500 ma and it would work as a trickle charger of sorts.

A doubt about htc charger.

I have an hd 2 and its a used one when i bought it. So i dont get the original charger. I got a samsung charger @ 5v, 700ma. But when i connect it, the phone shows usb detected. Though its charging, its pretty slow, i think the usb mode makes it. Taking only few 100-300ma only. And the charging takes long. I know htc need 1amp charger. But i cant get it here. So i decided to rip the charger and make some modifications ( like grounding or shorting the data pins- the middle two) . So i need a little help. Any of you guys having an htc original charger pls help me. Howz the data pins connected in the original charger? Are they shorted together or they are open? Or they are grounded? Pls help me those who know abot it. I want to make my charger form usb charging to default charging. It badly needed
send from my hd2 @ miui 1.12.2
That's weird. I've got original Samsung 0.7A charger here and HTC Desire HD does detect it as charger aswell and takes 1A from it. Shortening datapins together does usually convince most of phones that they are connected to wall charger. Maybe it's not the case for HD2.
Samsung Galaxy Phone Rapid Charger Modcheck this thread few under yours... speaking of shorting data pins.
HD2 is same as most, requires 2 data pins to be shorted together (2 inner pins).
Easy mod on most charger units. If charger is a cheap china job, the quoted 700mA figure could be optimistic ... temporary mod it by shorting data pins together & see how it performs ...
But there are 3 pins and not 4. So which ones are the middle?
send from my hd2 @ miui 1.12.2
Can you supply a good picture of this.
showlyshah said:
But there are 3 pins and not 4. So which ones are the middle?
send from my hd2 @ miui 1.12.2
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Sorry thatz an error. I mean 5 pin and not 4. All the pins are present( which are prsent in data cable)
send from my hd2 @ miui 1.12.2
Maybe this will help ...
Is it microusb?
You're supposed to shorten D+ and D-, but rather in charger. ;P
Mister B said:
Maybe this will help ...
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Is that micro usb?
send from my hd2 @ miui 1.12.2
Thakz dude
send from my hd2 @ miui 1.12.2
@ mister b and rebelloz ..
Thankz dude. I will click thankx button when i get to pc. Now i am frm phone
send from my hd2 @ miui 1.12.2
Very useful guide as I am facing the same problem. Thanks.
Useful guide i am also facing the same problem...
can anyone confirm if it worked for them? I made an adapter by shorting both data leads, but it didn't work for me. My phone will charge when switched off, but when it's on with both gps and data running, it barely gets enough current to charge the battery. Only my original cable works.
stanburn said:
can anyone confirm if it worked for them? I made an adapter by shorting both data leads, but it didn't work for me. My phone will charge when switched off, but when it's on with both gps and data running, it barely gets enough current to charge the battery. Only my original cable works.
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What device?
Signalling a dumb charger with MiniUSB (as opposed to MicroUSB) is less standardized. On most MiniUSB devices it's done by shorting pin 4 to pin 5, but it varies.
I could be wrong about this (someone please correct me if I am), but I believe the transformer inside the charger will need physically replacing if you're going to be pulling more current from it. If it's not too much over the charger's rated current it may be ok, but I've burned up more than one of them by hooking it up to something that draws more than what they were designed for.
xHausx said:
I could be wrong about this (someone please correct me if I am), but I believe the transformer inside the charger will need physically replacing if you're going to be pulling more current from it. If it's not too much over the charger's rated current it may be ok, but I've burned up more than one of them by hooking it up to something that draws more than what they were designed for.
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Click to collapse
Depends as part of the reason of the mod is to achieve full power draw of a acceptable rated charger by making the phone think it is connected to HTC charger & thus charge at mains rate of 1A or a little above rather than USB standard of 500mA. Most chargers of reasonable quality will supply 800mA to 1.2A & if you buy wisely a bit higher.
Issue arises on cheap china chargers with false specs that actually only handle 500mA & perhaps 800mA max for short bursts but when these are forced to supply more will fail.
A good quality charger will have no problem supplying full charge to a HTC handset ...
A good example - getting a non-iDevice to pull its full rated charge current from an iPad charger (charger rated 2.1A, but nothing but iDevices will pull any more than 500 mA from it without modifications.)
A good example of cheap Chinese chargers - the "1A" chargers carried by Monoprice. They're good for 300-400 mA at best. You won't burn them out as it's a fundamental current limit setting of the SMPS chip, but the voltage will droop if you try to pull too much out of it. It's the only Monoprice product I've ever been disappointed with.
Originally Posted by stanburn
can anyone confirm if it worked for them? I made an adapter by shorting both data leads, but it didn't work for me. My phone will charge when switched off, but when it's on with both gps and data running, it barely gets enough current to charge the battery. Only my original cable works.
Click to expand...
Click to collapse
What device?
Signalling a dumb charger with MiniUSB (as opposed to MicroUSB) is less standardized. On most MiniUSB devices it's done by shorting pin 4 to pin 5, but it varies.
Click to expand...
Click to collapse
sorry about that, I have the HD2. if I use the replacement cable with both data lines I shorted, it never charges when the phone is running. but if I swap my original cable the phone charges normally.
it's as though it ignores the shorted data lines, or maybe the HD2 doesn't really work that way?
I'm worried because my original cable is beginning to show signs of wear and tear.
Sent from my HTC HD2 using XDA

[WIP] Make a portable USB charger!

I'm going to show you how to make a USB charger where you can bring along with you almost everywhere. There are millions of ways to make one with various brains, ranging from the super cheap 7805s to insanely expensive IC (Integrated Circuit, not Insane C*cks) with awesome mind controlling thingies. I'm only going to show here 2 of the most popular implementations; The 78xx way and the MAX756 (Some TI or LT ICs are also viable alternatives) way. The 78xx way is by far the easiest and cheapest way (I can buy in bulk for a few cents a piece) and coupled with the battery holder and a fancy box to store it, it won't cost you more than $2 (Or $10 if you're buying from Radioshack or can't find the right guy to buy from). However, they drink your battery juice like a dehydrated guy drinks water (really!) and in the long run, it will be more expensive to maintain than the MAX756 method. However if you suck at soldering or are stuck with a lousy soldering iron (like me for now) you're better off using the 78xx method because I've fried more MAX756s with my blunt tip more times than you care to count (At that time, I ordered the wrong part and was stuck with 30 of the super tiny SoC chips which were an extreme pain in the a*se to solder with a fat iron). However, no matter what the cost is, I'm sure you will find it very useful especially in certain situations. Scoff at your friends while you are happily playing GTA3 on your power-hungry tablet while they bang theirs on the table because their battery's flat! Anyway, back to the topic, you can read up on the 78xx series here.
NOTE: THIS IS STILL CONSIDERED WIP WHILE I FINISH THE PROJECT AND UPLOAD THE IMAGES.
78xx METHOD
Ok, first off, you must choose what kind of 78xx to use. If you're powering a typical Android phone or iPhone you'll need 1A of power. You can tell the difference by looking at its size. the 500mA version will be quite tiny like your average sized LED, whereas the 1A version will be significantly bigger. However, if you are gonna be using the charger for a tablet such as the Touchpad or Galaxy Tab, you'll need to bring out the big guns. That's where the 78s05 comes in. It's 2A instead of 1A. However, (based on personal experience) you need more batteries connected in parallel (+ to +, - to -) for more combined amperage otherwise the 78s05 won't be able to power your tablet properly. Furthermore, as it outputs a constant stream of 2A, your typical phone likely won't accept the humungous amounts of current (believe me, I've tried). So you have to decide what you have to power at this stage.
...
...
Once you've decided what 78xx you choose to use, you'll also need:
-USB Female connector (Or MicroUSB Male port if you're feeling lucky). I ripped mine off a USB hub
-1-3 9V adapters (6AA Battery holder will suffice if you're a AA fanatic) as 9V batteries typically have very little power output)
-A fancy box
-Schottky diode model 1N5817 (For the tabloid version use ZHCS2000); a few just to be safe (Read about it here; its optional if you're feeling lucky )
--The function of the Schottky diode here is like a one-way road. The current can only flow in 1 direction and not the other direction to the end of your device.. I've damaged a HD2 with a faulty 7805 when the current went the opposite direction.
--NOTE: DON'T USE TOO MANY OF THOSE DIODES because each one loses a bit of current and soon you'll have not enough power to power your device..
Max756 method
reserved for later
Signing off
reserved for later
Great idea, gonna try it!
From my fingers to your eyez
going to try it thanks for the guide
Done something similiar few weeks ago.
Based on MAX608, it's very easy to solder, as it's huge DIP package.
Complete schematic, it also contains 5.1V Zener Diode (overvoltage protection)
I don't remember Schottky and transistor parameters, these can be taken from datasheet.
Powered from 2 1.5V AA cells works fine. That set of 4 resistors on USB D- and D+ pins is for iPods and iPhones to enable charging at all in 0.5A mode.
Rebellos said:
Done something similiar few weeks ago.
Based on MAX608, it's very easy to solder, as it's huge DIP package.
Complete schematic, it also contains 5.1V Zener Diode (overvoltage protection)
I don't remember Schottky and transistor parameters, these can be taken from datasheet.
Powered from 2 1.5V AA cells works fine. That set of 4 resistors on USB D- and D+ pins is for iPods and iPhones to enable charging at all in 0.5A mode.
Click to expand...
Click to collapse
Hmm.. I think some of the diodes might not be necessary.. Or maybe it's just the different ICs. Will post up the schematics when I have the time. Currently busy..
SGA-Sean said:
going to try it thanks for the guide
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Click to collapse
Lol.. I haven't even started documenting the project yet..
watching...
go on
arikyeo said:
Hmm.. I think some of the diodes might not be necessary.. Or maybe it's just the different ICs. Will post up the schematics when I have the time. Currently busy..
Click to expand...
Click to collapse
Oh, 5.1V Zener is there - its D2 (not necessary, just in case), also LED is just there to signal that's ON.
AFAIM Schottky is higly recommended in datasheet to lower ripple, haven't got oscilloscope yet to see what's the difference.
Be sure you check your datasheets. It only takes a very limited amount of circuitry to control the current throughput of any of the 78X05X models, and they spec them at 5% tolerance levels or less for regulation, so no output circuitry is needed beyond a basic cutoff.
Sorry for my absence the past few days.. Have been extremely busy with personal stuff including arguing with the bespoke tailor that she has misjudged my new $600 suit's khaki colour for the grey I originally wanted.. &#&$***#$
Anyway once I make a trip down to purchase the parts I will finish documenting this. Thanks for your patience..
thanks, it really help me in travel
This is actually very practical and can be done, given you have the right materials, basic electricity knowledge, and a rigged out hobby box to seal the components. I managed to construct a somewhat functional external battery for my iPhone 4 and besides and occasional d/cs, it served it's job.
If you like it easy and energy efficient you can use a "TRACOPOWER - TSR 1-2450" switching DC/DC converter.
- Input Voltage: 6.5V to 36V
- Output Voltage: 5.0V
- Output Current: 1A
- Up to 96 % efficiency
– No heat-sink required
- SIP-package fits existing TO-220 footprint
- Built in filter capacitors
- Short circuit protection
It is not as cheap as an 7805 (farnell.com 7.70€) but if you charge with a battery you don´t need any further circuit.
Just connect battery to input, output to USB+ and GND like 7805.
Normally your phone should start charging without any circuit to D+, D- (I checked my HD2 does).
Car-bon said:
If you like it easy and energy efficient you can use a "TRACOPOWER - TSR 1-2450" switching DC/DC converter.
- Input Voltage: 6.5V to 36V
- Output Voltage: 5.0V
- Output Current: 1A
- Up to 96 % efficiency
– No heat-sink required
- SIP-package fits existing TO-220 footprint
- Built in filter capacitors
- Short circuit protection
It is not as cheap as an 7805 (farnell.com 7.70€) but if you charge with a battery you don´t need any further circuit.
Just connect battery to input, output to USB+ and GND like 7805.
Normally your phone should start charging without any circuit to D+, D- (I checked my HD2 does).
Click to expand...
Click to collapse
I could not find this part number originally, so I pointed out the limiting capabilities of the 7805 series, but anyone that can get one of these and goes the 7805 route anyway is retarted! lol. Unless you just want to do it for fun, which lets face it, is 95% of the reason anyone would do this anyway! replacement batteries are like $5 of amazon for pretty much any device!
may be a better idea for cosidaration
you may use some power transistor with base voltage pulled to 5.1v using a 5.1 v zener diode, and that will give u a 5 v at o/p. and be sure to use a transistor which can handle min of 12v i/p and an o/p current of 2 or more amps. that will reduce the various voltage drops by using lots of components, and also less i/p voltage is required. like 5.5-6v i/p for 5 v o/p.
send from my hd2 @ dorimanx v.3.0.0.rom,with 2way rec kernal.
Car-bon said:
If you like it easy and energy efficient you can use a "TRACOPOWER - TSR 1-2450" switching DC/DC converter.
- Input Voltage: 6.5V to 36V
- Output Voltage: 5.0V
- Output Current: 1A
- Up to 96 % efficiency
– No heat-sink required
- SIP-package fits existing TO-220 footprint
- Built in filter capacitors
- Short circuit protection
It is not as cheap as an 7805 (farnell.com 7.70€) but if you charge with a battery you don´t need any further circuit.
Just connect battery to input, output to USB+ and GND like 7805.
Normally your phone should start charging without any circuit to D+, D- (I checked my HD2 does).
Click to expand...
Click to collapse
I think I've seen something similar around that costs a whopping 15 quid (even though the pound is decreasing in value...........) which translates to about $30 in Singapore dollars. Expensive and impractical for the most part.. If you do breakdown the parts within and the cost I think it'll amount to 10x cheaper..
This is definitely not a bad idea, and certainly easy to make. You can also make it as cheap or expensive as you like, from automated current regulation, battery status LEDs, multiple phones at once, Solar-Power, Nuclear-Reactor power, etc.
But I would recommend 3 1.5 v batteries in a holder, connected to a current regulator (Just in-case. You wouldn't want your precious phone to go up in a poof of smoke now, would you? Five dollars now, or Five hundred dollars later.), then some sort of way to connect to your phone (Either a Female USB connector, or if you want to make it specifically for your phone, get the right type Male USB connector for it).
I would also recommend Heat-Shrink tubing, Solder, and Painters tape (Like electrical tape, except it actually sticks to the wires.) Hot glue might also come in handy.

[Q] Make this tablet USB rechargeable ?

Hi I bought what I believe to be a Wopad V7+ ..
The ac/dc power supply broke and it's tough to find a compatible plug (very tiny) ...I'm waiting for a hopefully compatible charger to be shipped...
The tablet is officially not rechargeable/powerable via the micro-usb but I wondered if someone could point me to a (noob-friendly) way/HACK to make it rechargeable or at least powerable via USB ?
I can't post external links but I know it's powered by 5v 2A and you can find the pictures/information at dealextreme. sku104916 or at wopadusa.com store It seems to be AKA: HAIPAD M8 /Zixoon V78c / McPad V7+ / MOMO 1000 (BUT Resistive touchscreen)
You can see the internal components on a youtube video v=8SiLWpLCfus
there is pics of internal on twitpicDOTcom (/photos /bjlandsberger)
OR THERE : chinadigitalcommDOT com (/ haipad-m8-vimicro-vc882-t10830-10 DOT html)
or http twitpic DOT com ( /6i0ouo/full )
These pics/video aren't mine as I didn't DARE to open mine.
I apologize if my english makes your eyes bleed. Any help is welcome
USB can't provide 2A of current you'll have to buy a new charger
Sent from my X10i using XDA App
nugget1993 said:
USB can't provide 2A of current you'll have to buy a new charger
Sent from my X10i using XDA App
Click to expand...
Click to collapse
that shouldn't matter. It would still charge, just much slower. Just cut open the charging wire and a USB wire. Find which wire is positive and negative on your charging wire. connect the red usb wire to the positive wire in the charging cable. Connect the black wire to the negative wire. Insulate. It should charge.
Note- if you switch the wires, you can permanently screw up your tablet.
This. Just be extra sure not to cross up your wires, I did this once with a USB hub and fried the board. It literally left melted plastic on my desk.
Epic_VS said:
that shouldn't matter. It would still charge, just much slower. Just cut open the charging wire and a USB wire. Find which wire is positive and negative on your charging wire. connect the red usb wire to the positive wire in the charging cable. Connect the black wire to the negative wire. Insulate. It should charge.
Note- if you switch the wires, you can permanently screw up your tablet.
Click to expand...
Click to collapse
It's a 3.7v battery which means it can charge at 5V. Looks dooable with a .5A Regulator and a 1ohm resistor... I'd try this and if it fails, then you've tried and failed
So it is a 3.7 but the problem is that is a raw battery pack as in no protection, no regulation, no charging circuit. If you want to sit there and babysit you could attempt to put 5.0V on the power lines and that might work. I would say it is dangerous to do so.
Epic_VS said:
Connect the black wire to the negative wire. Insulate. It should charge.
Note- if you switch the wires, you can permanently screw up your tablet.
Click to expand...
Click to collapse
No risk of fire/explosion ? What would be the best way to insulate ? heat Shrink tube + tape ?
I planned using a ACDC inwall 110 to USB 5v 1A out adapter, would it be risky ?
Will I have to babysit it to prevent a fire ???
Errrr...
.5A Regulator and a 1ohm resistor.. Maybe with a graph and picture I could figure how to do it ... I don't know anything about electronic/tension ohm's law.. I don't want the battery to explode and rip my head apart.
No matter, go for it, it will be OK, all li-ion batt used in mobile device have a small protection circuit in it(unless specified) ur batt too have it, use heat shrink tube, a 100-300ma USB current can't make it explode.
Sent from my HTC HD2 using XDA App
moto xoom...
Hmm....is this possible to do? If so I would like to try it on my Xoom, the little pin charger is annoying I bent the hell out of it. Micro USB would be stronger . All pros no cons.
For the most part putting 5V on a 3.7V load is not overly dangerous. In order for you to charge a battery, the voltage being applied to the battery has to be greater than the potential storage of the battery. In this case, greater than 3.7V. My blackberry charger is 5V regulated output.
We use 3A power supplies all the time to charge 12V batteries. The voltage we set it to is 14V. These power supplies aren't smart. They just dump current. The higher the voltage pf the battery gets, the lower the current gets as it starts to resist the current that is coming into it. Even your cars alternator puts out 14V and yet the car battery is 12V. For the most part, the actual voltage of batteries is 10%-15% higher than what it is rated at as well. So your 3.7V battery is more like 4.05V - 4.20V when it has a full charge.
But, this is not going to give much big problems. As the current is only 10-20% of the original batt amp, so it will be ok, but for high current ratings the voltage must not be more than 1-1.5 v higher than the batt voltage.
More over the ditachable batt of most phones /pda have inbuilt i-v regulator inside the batt. It will prevent overcharging and deep discharging on most cases.
Sent from my HTC HD2 using xda premium
WOW thanks a lot for the informations, if my RMA doesn't go as I want I'll probably settle to try this and keep this post updated.
Thanks a lot. XDA is great.
My two other (unanswered) threads:
http://forum.xda-developers.com/showthread.php?t=1477288
http://forum.xda-developers.com/showthread.php?t=1480517

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