For those interested, I thought I'd share my work that saved me $10 - $30. Since I never used the USB cable that came with my 8125, I cut the cable and connected it to a cigarrette lighter plug. There are 4 wires in the USB cable (yellow,,black,green,white); 2 wires in the plug(red,black). Connect red to yellow, and black to black. The white and green wires can be twisted together to be out of the way, they are NOT connected to any thing. Voila! a homemade car charger that really worksP.S. Check out this website: Funformobile.com. Today animations, ringtones, all sorts of cool stuff for your 8125.Cingular 8125ROM 2.25.11.1
12volts straight to the dome! Better stop up and batteries!
Ya know, the real 8125 car charger converts the car batt 12VDC to 5VDC and regulates the amps to 1. Just thought Id throw that out there!
Take a look at this then!!! I had a camera that i droped and its in little bits, so i just cut the holder abit and now i have a phone holder for when i am flashing roms or doing other things on it!
calouro said:
Ya know, the real 8125 car charger converts the car batt 12VDC to 5VDC and regulates the amps to 1. Just thought Id throw that out there!
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Click to collapse
That's funny, I saw the "real" car chargers, and not 1 has a "built-in" converter or step down transformer from 12V to 5V. All it has is a cigarrette lighter plug and the charging cable like the one I made. Is the converter in the cigarrette lighter plug? I use my homemade charger every day in my truck, and have had no problems. My phone would had fried when I first tested it. If anyone else decides to make their own charger, you're doing this at your own risk. I am not responsible for your stupidity or lack of mechanical skills. I'm just sharing my work.
hotdog53 said:
... I am not responsible for your stupidity or lack of mechanical skills. I'm just sharing my work.
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Click to collapse
So, what you are saying is that it was stupid of you to create your own?
Yes, the original car charger has a down converter within the plug - sooner or later your device will either blow up or your battery will break.
I do not recommend this to anyone! You better keep your original USB data cable and buy you a real car charger for $5.00 (and up).
Going hotdog53's way is saving money on the wrong end ... your WIZ is a bit too expensive for that, isn't it?
Junner2003 said:
So, what you are saying is that it was stupid of you to create your own?
Yes, the original car charger has a down converter within the plug - sooner or later your device will either blow up or your battery will break.
I do not recommend this to anyone! You better keep your original USB data cable and buy you a real car charger for $5.00 (and up).
Going hotdog53's way is saving money on the wrong end ... your WIZ is a bit too expensive for that, isn't it?
Click to expand...
Click to collapse
Come on now, how in the heck can a converter or step down transformer be made inside a plastic cigarrette lighter plug??? Visit Cingular's accessories website for car chargers for 8125 or8525, and click on the view details located at the bottom of the car charger pic. The home charger with the big black plug has a converter to step down 120V. I used the pistol type cigarrette lighter plug. Where can I get 1 for 5 bucks? I'll buy it for a spare.
Almost every vehicles electical system runs on a +12V DV Current. A standard cigarete lighter is 12volts. and does not have a transformer. By tying in the usb cable directly to the cars 12V system you are now stuffing massive amounts of electricity into your phone at an unregulated rate. It is highly likely you will burn out sensitive resisters and capaciters in the phone because they are very small and not designed to handle the current. Also charging a battery too fast is bad for it regardless of NmHi, Nicad or Lithiom. If you charge rate "amps" is too high you'll permanently damage battery cells "cook" them. One thing also is that it could actualy draw current from your phone. What I mean is that your phone may plug into the cable and show that it's charging but it's actually draining the battery.
I'd spend the $14 at walmart for the motorola "mini usb style" charger...
Option "b" is to buy a cheap power inverter that converts the current from dc to ac and you will be able to plug in your standard wall charger.
Thanks for this very informative reply. I've used my homemade charger for several days now, and my battery has no problem charging from the home charger. True, the cigarrette lighter is 12V, but the vehicle's voltage regulator controls the amount of voltage that is put into these 12V receptacles. For safety, a fuse would blow before anything drastic happened.
Yeah, but if my truck's Not running, what does the voltage regulator do? NOTHING! Hey everybody who replied and read this thread, I stand corrected and apologize for my sarcasm and knowing all! The protection IS in the plug, and fortunately the pistol plug I used was from another phone car charger. I agree with all the rest...DO NOT MAKE YOUR OWN!SORRY EVERYONE!!Cingular 8125ROM 2.25.11.1
Hi guys,
i have a SGH-i780 Smartphone and i am quite happy with it. The only negative aspect is short battery lifetime when beeing always online for push-mail.
Therefore i would like to have a docking station for my device, where i place it and it is been charged. But as the f******g Samsung developers placed the charge/sync connector on the upper right side of the device i would always have to place it in docking and connect charge cable.
Therefore i thought about modifying the phone which means making the 3 battery connectors accessbile from outside to connect the external charger box (including charging electronic!).
And here is my question: do you think connecting a charging electronic directly to the battery while it is inside the phone will harm or destroy parts of the phone? I am wondering whether the internal charging circuit inside the phone will get hurt by connecting another circuit in parallel ...
Thanks for your comments!
For sure this could hurt your device...............
In this case I'd say the risk isn't worth the reward. The risk is that you fry your phone, and at worst it sparks and causes other damage. You can have it check for mail less often, unless you need your email to be live.
such heavy modifications never go without harm to technology.
It simply is not designed to work that way, so you'd be better off with a docking station or a better Powerpack.
You can find those on Ebay for pretty low prices...
thanks for your replies!
I also thought about wiring the +5V and GND pins from the USB connector to the bottom of the device and connect a power supply directly (which but be the way it is thought to be) but the usb connector is very very tiny and i doubt i will be able to connect and solder the cables to the right pins ...
any furhter ideas?
not really no... trying such delicate soldering quests is generally not a good idea without the proper Equipment.
Whatever you do to modify your phone, it will void your warranty and you'll not get a replacement device if you trash yours...
Don't do this!
By bypassing the phone's own charging circuit you are removing any sort of overvolt protection!
Although I am not familiar with this phone and your post is somewhat hard to understand, I take you usually sync it, then take the battery out to charge that separately with another cable?
If that is the case then, no, don't move the connector so you can charge directly to the battery! It will be potentially very bad for the battery and phone.
Out of the question
DO NOT under any circumstances play with your battery.
What you were taught in your physics class do not apply to microelectronics!
There are many 5V+ out there and ALL are different!
While rms value is the same, the waveforms of the current/voltage can be any imagineable. So, the best thing to do near your cradle is to pin a sign "KEEP OUT!"
Technically, you could create another charger that connects directly to the battery. There are dozens of ways.
BUT, since you asked, then you don't understand how. Assuming it is a liPo or LiIon battery, if you charge it wrong, the resulting explosion and fire will be nasty.
Why not get a second battery in an external charger, and just swap them.
worwig said:
Technically, you could create another charger that connects directly to the battery. There are dozens of ways.
Click to expand...
Click to collapse
Do you mean while it's inside the phone?
worwig said:
BUT, since you asked, then you don't understand how. Assuming it is a liPo or LiIon battery, if you charge it wrong, the resulting explosion and fire will be nasty.
Click to expand...
Click to collapse
I already have another appropriate charger because Samsung ships this phone with an charging box.
worwig said:
Why not get a second battery in an external charger, and just swap them.
Click to expand...
Click to collapse
Because then i would always have to take a second battery with me, every time! That's awful!
I just want to have a docking station, that charges the phone while it's plugged in ... without terrible wiring needed. Then i can make sure the phone is always fully charged when taking it.
I attached 2 pictures showing you my 2 ideas:
1) wiring the external charger directly to the battery (but of course this would also mean connecting it directly to the internal charging circuit of the phone!). I fear this would damage the phone!
2) wiring the power supply to the power supply connector. This should definitely work, but soldering the cables on the tiny connector will be a pain!
Thanks for your help!
Ok guys, so nuclear war stroke the planet, your brand new tv and pc got busted in the initial attack and you're left with your precious HD2 running some custom rom and about 16-32gb of storage. Hope you don't get borred, there won't be many apps on marketplace, or even a marketplace (servers got busted by the nuke )
Now to get more seriously i can't figure out why i would need a phone able to be powered on 24/24. But i guess at least it could be useful on camping trips or stuff like this.
This is the start of a project, are goals are something like this:
1. reverse engineer the charge algorithm used by HD2 (in involves at least 2 charging modes each with 2 stages, as i know so far)
2. assemble or buy a 5-10W solar panel (only the panel and a Schottky type fast diode)
3. get myself some old laptop batteries and strip them down for cells and controllers.
4. design and assemble a cell pack as a buffer between the solar panel and phone
5. design a switching mode voltage stabilizer and make a custom usb hub in order to also have usb host functionality if i feel geeky and need linux
6. design a charge controller for the cell pack when using solar power.
7. put all things together and test
The goal is simple. Although there are solar batteries that provide some extra juice to laptops or pda's they function somewhat like 2-3 hours discharge, about one day in full sun to recharge.
I want a system that can power a full load working hd2 (worst scenario) non stop (day and night) including cloudy days, nuclear winter or whatever. The system must also be able to power about 3-4 usb devices and sustain a full 500mA drain on each port while still being able to power the hd2 non stop. Aaah, yes, the thing must be portable, plug&play, reliable and maintenance free. At most, it should have the size of a regular 15 inch laptop and about 2kg weight (all things included).
Stage 1 completed
So i figured out how hd2 charges it's battery. It's pretty simple actually.
Charging is made in the same way for either wall charger or usb charging. Same pins are used. However, when the wall charger is used, charging current can be as high as 800-900mA. This will decrease to some 20-30mA when the battery will be almost 100% charged.
If you however connect the usb data pins to hd2 and to something (computer, hub etc) hd2 will change the charging mode to usb. This feature ensures that when connected to a pc, the phone will never try to get 8-900mA from a 500mA usb port pretty neat. Instead, maximum charge current is limited to about 400mA.
If you get access to the usb wires inside the cable you can trigger either mode by simply disconnecting or reconnecting the data pins (green+white on standard usb cables). This is useful because i can devise some means of redirecting the charge current to either external battery (let's say after a night of use for the hd2) or to the hd2 if .. for some reason it's internal battery is discharged.
A usb enabled pic microcontroller (say 18f2550) can be used to control the charging process of either internal or external battery by simulating a pc connection, thus enabling hd2 to switch to low current charge. However if i'm guessing right, a simple usb hub could also do the job as it also contains a microcontoller that "knows" the usb protocol. So because i will use an external powered hub for linux, I'll try to use it also for switching between charging modes. Besides is more easier this way and i (or others) will be spared the time needed to program a microcontroller, or fabricate a pcb for it and it's corresponding components. And.. in case of nuclear attack there won't be any radio shack or electronics store where you could buy microcontrollers
Stage 2 completed:
Well i got myself some time ago a cheap 10watt polycrystaline solar panel for use with a robot i'm building. It was about $50 here in Romania. I guess i'll be using this one, even if it's quite big (something like a 16 inch laptop). Anyway i could also power other things with it. Will do some tests, and if it's suited for the job, it will be used. It arrived completely assembled so it also spares me the trouble and time of connecting individual cells into to form a solar panel.
Update : completed, will use the spare 10watt panel, until a new one arrives.
Stage 3 completed:
Got some 5-6 old laptop batteries. Stripped them down and got some ~30 cells. I'll test them out and sort about 4-6 of them.
Stage 4 completed: I'm currently sorting out some cells. As far as design goes, the capacity of the "extended battery" will be 14400mAh (single charge, using no solar power). That could easily power a full 15 inch laptop for about 4 hours, so i guess hd2 will have no problems staying alive for one night until next day and the sunrise to kick in for the solar charging to take place
Stage 5+6 completed:
There won't be any linear voltage stabilizer design for the buffer between the battery and hd2. They are quite inefficient with 30-40% power lost in the form of heat. Switching mode stabilizers+converters will be the way for this design. Found a ready made voltage stabilizer (converter) that's suited for the job , Saved some good hours that would otherwise have been spent on designing one from available parts.
Stage 7: yep, i'm now building the damn thing. I've simplified the design as much as i could, while keeping it safe for the phone, i guess the project will be possible to make by anyone with basic soldering skills.
apr. 13 - update: construction delayed due to one cell failure (the difference in internal resistance between the cells was greater then i expected). Will now search for a replacement, recalibrate the battery pack and recharge. However I expect that the battery module should be ready by the end of this day or tomorrow.
ok then.. it was built, it was tested and i'm already using it or at least.. trying to figure out a use for it
Anyway, if you're the camping type, if you feel geeky or wanna make a eco-friendly charger for the hd2 (or other usb charging enabled things) here's how to build one
You'll need the following materials:
- patience, this is a long post, try not to get bored while reading it
- some basic electronics skills, basic understanding of components, measurements and circuit troubleshooting (this is not a beginner project i guess, as hard as i tried to make it, if done improperly... well of course, you risk killing the poor phone in the process).
- some second hand laptop batteries, 3-4 would be ideal, they can be kind of old, but must be functional to some degree.
- a cheap usb charger used for cars, the one that plugs into the cigarette jack OR some good electronics skills to design a switching power supply. Guess most of people will go with the first option, in order to be more helpful i also designed this circuit using this option. You should buy the cheapest adapter, the cheaper the better. That's because the expensive ones have a feature that enables them to stop working if the voltage of the car battery drops to a certain point. That's supposed to be some sort of protection not to allow the car battery to discharge and thus preventing you to start your car. We don't want this protection, we want to be cheap asses, we want dirt cheap. However the adapter you want to buy must deliver 5V at around 1-1.5Amps minimum. 5Volts at 500mA is to little, it will simply kill itself when you start the thing once it's completed.
- a standard usb hub, any will do. This is if you want usb host functionality or use linux.
- a 5-10W solar panel. The bigger the better - it will allow to recharge the buffer battery (the one you'll be building) at a faster rate. This is the single most expensive part of this build. If you simply want an external battery for the hd2 you can skip the panel, if you want solar charging.. this is .. of course, a must.
- one fast rectifier diode or a schottky diode, you should buy it if you use a solar panel, the supplier of solar panel could also recommend one to use with that specific panel. We have to use one, this will make sure the current goes from the panel to the battery, not the other way around.
- bunch of wires, a multimeter and a soldering tool witch you're not afraid to use.
- a variable power supply, either it be a wall charger with variable output voltage, a laboratory power supply, or some charger that can output anywhere from 3.6 to 4.5 volts at anywhere from 300mA to 1A. Any combination will do. This is required only once in order to precharge the cells to a specific voltage.
- one switch or something similar in order to ... switch the thing on and off.
- spare time/understanding wife/coffee etc
1. Ok, first of all you need to get those laptop batteries open. Use some sharp tool, your karate skills or whatever necessary to crack those batteries open and expose the individual cells inside. Be careful not to damage the cells in the process, at least if you use some sharp tools. Once exposed, the cells will be linked to each other, you need to separate them by cutting the wires or metal bands that links them. Once done sort them out, if you have multiple batteries, sort the cells from each battery in a different case or basket or whatever you want, the idea is not to mix them.
Here's mine:
2. You now need to measure up individual cells with a multimeter. You're looking for the voltage rating of each cell. If you find cells with 0 volts, they're dead. If you place the multimeter in continuity testing mode and the 0 volts cells are showing continuity across their leads, yep.. they're really dead. Never use these. Good cells have anywhere from 1volt to 3-4volts.
Once you selected your good cells start forming a pack. The idea is simple. The more cells you put, the longer the thing will last. Standard laptop cells are rated to a minimum of 3.7Volts and 2400mAh. Each of them is almost double the capacity of the standard battery that comes with the HD2. However since you're going to use second-hand ones, they will have sign of usage, a smaller capacity then that of a new one. Still they will perform at least the same as hd2 battery in terms of battery life. Minimum configuration starts with 2 cells, i recommend 4 cells as a decent start but you can go and add more cells if you like. The more cells the longer battery life but at the expense of added weight. My choice was 6 cells. If you had 2 laptop batteries and each of them had 6 cells, you can make your pack on anywhere from 2 to 12 cells.
Let's say you choose 6 cells (always an even number). If 6 is you choice, you will need to divide that number by 2. So you get 3. You need 3 working cells from the same laptop battery to form a pair. Go back to the place you kept the cells and select 3 cells, NEVER mix cells from different batteries. These 3 cells you have (first pair) will need to be linked in parallel connection. The negative ( - ) of each cell is linked to the negative of the other and the positive to the other 2 cell's positive. We'll get there, but at a future step. Now we need the second pair of 3 cells. Again look in your cell basket and try to find 3 more cells from the same battery. This battery may be different then that first one you selected cells for the first pair. Yet again, the 3 cells must come from a single battery, no mixes. And.... again, these 3 cells must be placed in parallel. So if we already imagine them connected, we would have 2 pairs, each of them with 3 cells linked in parallel. The 2 pairs must be linked in series, so the minus of one pair will go to the plus (positive pins) of the other. The unconnected pins of each pairs (one minus one plus) will be used for voltage supply - you'll get the combined voltage of the cell pack here. If i were to draw this things for you to better understand.. it would look something like this.
green is one cell pair, orange the other. The black things are wires. This are the connections for a 6 cell pack. If you have 8 cells, you will make pairs from 4 cells (2 pairs). If you have 4 cells - the pairs will have 2 cells. A charged cell will have something like 4 volts. A pair made up of several cells in parallel will still have 4 volts across it's leads, but the overall current capacity of the pair is increased by the number of cells it contains. So if you have 3 cells each with 4v and 2200mAh, the pair will have 4 volts but with 6600mAh. If you place 2 pairs in series like on that drawing, you increase the voltage of the group by the number of pairs you add while still having the same current capacity. So if you get 2 pairs of 4 volts and 6600mAh, you will have 1 group, 8 volts and still 6600mAh. That's the total output of your pack. Because hd2 needs 5V (not 8 !!) we need something to decrease the voltage from 8 to 5 volts. That's why we need that car usb charger. It normally uses the 12V available at the cigarette jack to output 5v your phone can use. Cheaper ones, can use 8 volts, or 7 volts (lower voltages) because they don't have a circuit to prevent deep discharging the car battery like expensive one have. We need one without this circuit, because our battery pack only outputs 8V. So the car usb charger will take the 8 volts at it's input and give us 5volts at output.
3. before linking cells to each other, you need to charge them to the same voltage. Use a charger/power supply etc. I used a lab. variable power supply, if i had none, my weapon of choice would be a nokia standard wall charger (or another brand), older ones, i would cut off it's jack, expose the wires and connect them to my cells, it outputs 3.7 volts, enough to charge each cell. So charge each cell to about 3.7 volts. You will need to connect the multimeter in parallel to the cell and monitor the charging process. When a cell reaches 3.7 V disconnect it and charge another one, until all of them have 3.7 V. After this, leave the cells for one day. Next day you will be measuring each cell again. If one of them drops charge by it's own and you find.. let's say 3 V, you got a defective one, back to step 1&2 and select other cell pairs. If all cells still have the same aprox. level (somewhere around 3.5 to 3.7 volts) you're good to go.
Here's one cell linked to my voltage supply.
4. start thinking of either a case of something to contain your build. I used copper plated pcb (from electronics stores, radio shack etc). I will be connecting my cells to this thing, kind of like a pcb assembly. You may use some plastic housing and connect the cells with wires and secure them with some glue. If you have experience working with pcb, etching the copper layer and such things, feel free to try using pcb.
Here's my blank pcb for this job - i've already cut it to required dimensions. It's the orange metallic thing in the center. Beside it you can see my hub and the usb car adapter i will use.
5. disassemble (i repeat disassemble.. no more karate skills) your hub (if you're going to use one) and your car usb adapter. My usb adapter looks something like this.
The hub interior will look different, we'll get on that on a later step. Anyway, speaking of the usb car adapter, i'll be needing that small pcb with the components, so i'll remove it from there. The board contains the switching mode voltage converter, yummy yummy, i want that. It basically has 1 chip that generates a pulse signal that is feed to the input of a power transistor which pulses the input voltage across a coil. By autoinduction the coil produces another current, other components rectify and filter it so the second smaller current, produced by the coil, it's basically what powers on the devices connected at the output. In simple terms .. that's how it works. Again.. we need this, don't break it
Mine has a funny oval shaped form, so i'll be cutting my pcb in order to insert it inside.
There are 2 wires coming out of the small board inside. That's were the cigarette jack was connected. We will connect our cell pack to that, so you might wanna remember their position. The red one will be the positive one, black being negative. In a cigarette jack, the center pin is always positive, so if your wires have other colors, the one that's linked to the center pin will be the positive one.
6. Look for a way to place the cells inside your casing or on your pcb. Since i will do a pcb with them, i'm trying to find a possible placement for them.
this was one way, but i figured it was easier for me to simply place each pair on a line and form 2 single lines of cells instead of 3. Once done, i begun drawing the pcb with some paint marker. I will then etch the pcb, so only the paint covered areas will remain.
here's the pcb after etching, i'm connecting various wires to complete the cell pack circuit before connecting the cell themselves.
If you're using some sort of case, it's time to begin assembling your cells together. Use the solder gun or whatever you have for soldering to attach some wires to the each cell leads. Li-ion and heat aren't good friends, be as quick as possible when soldering, you don't want to heat up the cell too much. If it starts to make any strange noise, hiss or is venting anything from it... run away, don't touch it, don't throw it.. simply leave it and run away. Of course, this is a very rare scenario.. but take your safety when working with high reactivity materials like li-ion cells.
You want to arrange the cells in that paint draw up in the post. 2 pairs, linked in series. First solder wires to make one pair, then the other, then connect the pairs to each other. If you use a case, use some insulator to cover the solder points and to avoid some accidental short circuits in the future.
Back to my pcb solution, here's my assembly.
7. If you want to use an usb hub, you can try to salvage some usb port from an old pc or laptop's motherboard. This way you could avoid using a permanently attached wire to the device you're building in order to have the hub connected to the phone. I found an old laptop motherboard with an intact usb jack.
i remove the usb port from it and soldered on my board.
8. Next you need to connect the car usb charger's pcb to the battery pack you assembled. Basically the 2 wires from the charger must be linked with the 2 wires from the battery pack. Insert a switch on the cable in order to be able to turn on and off the whole thing. In my case, i'll now connect the car charger's pcb to my pcb, in the portion i've cut.
9. now you need to modify your hub to be able to power on hd2 during usb hosting mode. There's a link in the linux section (ubuntu for hd2) about this, you may want to read that also. I basically soldered a wire across each hub's usb port positive pin (the 4 usb jacks) and the input usb jack. The ground connection is the same for all jacks. So all jacks including the one used for connecting to a usb host device (pc) have the power pins linked together. Those 2 power pins must also be linked to the output of the usb car charger so that when you power up the thing using the switch, the charger also powers up the usb hub. After you solder all the wires, also insulate the soldering points and secure the hub in your casing along with the battery pack and usb car charger's pcb.
Here's mine, it was soldered on my pcb.
as you can see, there are some couple of wires coming out from it. Those need to be connected to the phone for me to have usb host functionality. So i'll connect these wires to the usb port i've mounted at step 7 so i can use a standard usb - microusb cable to link this thing to the phone. If you want to make it simpler, cut out a usb - microusb cable and directly solder the wires onto the hub's pcb as shown in the guide on the ubuntu linux thread for hd2.
In my case, i use that port i salvaged, as i said before.
10. assemble the whole thing and carefull inspect the connections. The order of this will be - battery pack - linked to the car usb charger - that's linked to the hub power pins (for each usb port). You'll then have one usb port for use when requiring usb host functionality, 4 usb ports for connecting all sort of usb slave devices, and one usb port (the one that it's soldered to the car usb charger) for use when you want to simply charge your device normally.
Here's my build. I've also placed a fuse between the battery and the usb charger, so that in case of malfunction it breaks the circuit. The fuse holding pin is the black thing at the opposite side of the usb hub. Near the pcb, you can see the fuse and it's cap.
11. Check again all connections. when ready, press the switch and bring the thing to life. Use the multimeter and check all usb ports voltage. You shoudn't have more then 5.5Volts and no less then 4.5Volts. If you do, then you did something wrong, turn off, disassemble and recheck. If you did it right, you'll get a voltage inside the above interval. Inspect the device once again and make sure all things are safely placed and secured inside. Try plugging some cheap usb devices you may have, a mouse, usb flashlight, another hub etc. If they receive power and all it's ok you may try to connect the phone.
Voila.. usb charging from the ghetto style external battery.
And here's a small video of preliminary testing (i haven't yet tested the usb hosting capability but i have no reason to think it will not work). At this time i didn't placed any switch on the board so i switch on and off the thing by placing the fuse inside the holder or removing it
http://www.youtube.com/watch?v=yf6kRpNNqkw
Next step... maybe some of you may think.. well how does this thing recharge when the batteries are depleted. At this stage the battery pack is recharged by connecting a 8.4 voltage supply across the battery pack leads (wires) but the next logical step will be adding the solar panel to the build and securing this pcb to the back of the panel. Then.. further testing. I'll be keeping the panel and that rectifier diode handy. This is still work in progress.
When are we getting it?
i guess it will take about 1-2 weeks to do the job.
i'm also involved in 2 more projects, it could be done as soon as i finish my automatic dog feeder with video-streaming over internet, food sensors and audio feedback. )
facdemol said:
i guess it will take about 1-2 weeks to do the job.
i'm also involved in 2 more projects, it could be done as soon as i finish my automatic dog feeder with video-streaming over internet, food sensors and audio feedback. )
Click to expand...
Click to collapse
Hey facdemol I am not as versed in electronics as you are my friend. So my question to you is this is something that someone with a fair level of intelligents can attempt also? Secound is this, is the list you give in your first post all some one needs to try this? I would really like try this myself and maybe correspond my findings with you. Also thank you totally of you ammazing knowledge filled posts here on XDA.
lol.... Im not sure how to respond to this
Cant wait to see how it turns out, best of luck
sounds interesting!
Good man, keep us updated however things turn out... you sound like someone who isn't afraid of experimenting with electronics for the thrill!
Sent from my Nexus One
Wow! Pretty interesting
Hey facdemol I thought you might like to check this article in the Portal out if you have not already. Looking forward to hearing back from you here on your project.
good article, was inspiring
stage 2 and 3 are completed. Now working to design a high performance dc-dc (switching mode) converter that would take 8.4V input and give me some 5V @ 2.5A output for hd2's charging and the usb hub. Some work needs to be done here and some careful testing, if for whatever reason this converter fails, hd2 motherboard could get fried Working on a way to implement some safeties, also i'm studying the way older pda's and pna's used switching mode power supply's and converters. I'm thinking i could either salvage one of these modules or build one specifically for hd2.
Update : found a way to make this pretty DIY for anyone with basic electronics skill (so that you can avoid designing switching mode converters, making PCB's, winding coils etc).
I found some dirt cheap car adapters that output 5v (pc usb jack) and can be used for various usb charging enabled devices. I'm testing to see their performance with my custom battery pack and the solar panel. Results are pretty good so far, i managed to run them stable at arout 5.5-6Volts input voltage. 2 of these will be required for this project (2 amp max current) or one if the output transistor inside is changed or a heatsink is mounted on it. I will come back with results and in the end, a guide with the required modifications.
The second post contains the updated progress on this project.
Third post will contain some sort of guide for a DIY assembly of such device.
These are updated daily.
If everything goes smooth, i guess i will posting some pictures and guides to build such things, by the end of this day or tomorrow.
Current features of this design :
- 10watt solar panel module
- 14400mAh battery module - cell pack designed as 3p2s
- 2 charge modes (slow - similar to a pc's usb port and fast - similar to hd's wall charger)
- 4 powered usb ports (usb host capable)
- 1 high-power usb port (it can charge any device requiring 5V at around 500mA - 1500mA)
- uses standard usb-microusb cables, no need for other hacks or special cables
- feels geeky
facdemol said:
The second post contains the updated progress on this project.
Third post will contain some sort of guide for a DIY assembly of such device.
These are updated daily.
If everything goes smooth, i guess i will posting some pictures and guides to build such things, by the end of this day or tomorrow.
Click to expand...
Click to collapse
Sounds greet I will bee waiting to see what you have come up with man, this could be something that can change how we can use our HD2s on the go. n
Keep up the good work facdemol, I am also waiting to see if you post any more power consumption results in your other thread.
I would like to ask anyone reading this to help vote this to be published in the XDA portal by clicking the vote bottom at the top right of the first post by facdemol, he deserves recognition for his great work with this project and his others.
Very Interesting ! Good luck with the project! will be following to see what develops!
I love this. Great concept.
it took a while to charge the independent cells to the same level and to form a pack. The charge alignment is a must, otherwise, the battery back will discharge at an uneven rate among each cell. One done properly it should allow the maximum battery life and no future maintenance.
I've done some testing on it, already hooked up the hd2 to this thing, it's working properly, both charging modes, usb host etc. I guess i'll come back today with the guide and pictures to make this, it took the better part of yesterday to manually charge/discharge each of the 6 cells in the pack.
updated post 3, half of the buid is already done and operational. The battery and hub+charger module needs to be linked up to the solar panel and some of case to be built.
There are some pics and one video with the thing working. Just basic testing for now, i just finished it.
Very interesting...great job mate...
Attention do this at our own risk as it may damage our phone.
My used samsung galaxy pocket-neo was becoming impossible to charge causing me to break the adapter cables with constant wiggling and balancing acts to get it to work. I took it apart and the micro usb socket looked like an extremely difficult soldering job to replace.
The solution I am using for more than a month with no adverse effects is to cut the plug off and strip the 2 power wires at one end of an old usb cable. There are 4 different coloured wires, red, black, green and white. The green and white wires transmit data, whilst the red and black are the power lines. Red is positive, Black is negative. The sleeve of the cable has a metal mesh which is not necessary for my purposes so I electrical taped it back onto the cable.
The next step is to remove the battery of the phone: I have only done this on phones with removeable batteries. The ones I have used have three terminals; one is plus and one minus, the middle one is for a thermistor in the internal of the battery so that it doesn't overheat. Check the plus and minus with a tester to be sure and look at the way it mounts into the phone. The corresponding terminals in the phone are where I connect the wires.
Now here is the complicated part, - or negative(black) goes to the one negative copper pin in the back of the phone. The positive +(red) wire however needs to bridge the other two pins for reasons that I would like to find out. The white and green wire got taped up seperately to avoid short circuits and I replaced the battery to hold the wires firmly in place and closed the back of the phone. Plug the phone into a charger or external power pack (DC 5v) and it will work fine with no overheating, I suggest this be monitored for a while as it may vary with other hardware.
There may be better ways to do this, as far as I can tell in my case I am not actually charging the battery, instead the phone is running directly from the external power source. The strange thing is that the software(CM11) battery icon slowly discharges and after about 10 hours tells me I need to charge the battery but never turns off and when I restart it is immediately back up to full.
I have tested with a normal cable and the micro usb is still working even though it is still only working when I constantly wiggle the cable, I have cleaned it and as far as I can see its not going to ever work properly.
It would be good to know why the battery does not chargewhen using this method. I imagine it has to do with the internal workings of the phone that control the charging, discharging and battery temperature.
Making the old hardware live longer.
Replacing the micro usb is doable with a hot air gun a pair of tweezers, a clunky spring loaded solder sucker, a flux pen and two pairs of 3.5 x magnification reading glasses. You dont need any fancy rework station or microscope, assuming you have steady hands, reasonably good eyesight, and some soldering experience. I just tried this myself yesterday and fixed and Ace 3 and two S3 mini boards from my junk pile, and while it was a little tricky, it didn't require any brain surgery skills, just care, patience and some previous smd soldering experience.
Proceed as follows, mask off all of the surrounding components with kapton tape, apply lots of flux from your flux pen, then heat the plug carefully, pointing the hot air across the plug and away from the rest of the board. Grab the (hot) metal can of the USB plug with the tweezers, and gently lift it. Only remove the plug when all the solder is melted, and it feels loose, to avoid pulling off any tracks. Remove those tracks, and the phone is for the bin. Next, clear any holes that are required to mount the new plug, take care at this stage, as it is imperative that the replacement plug sits flush on the board otherwise the pins on the plug, wont touch the pads on the board, and worse still, you wont get the case back on at the end of the process.
To fit the new socket, clean the pads... no really clean them.... now make sure they are clean, and then flux them and tin them. Fit the new plug, and check that it sits flush to the board. Tack down one metal lug only on the can of the new plug. Check again that the pins are lined up, and carefully drag solder them. Check for shorts. Check again... clean the pads and check again. If you are happy, tack down the remaining three lugs, make sure they are flush and that there are no blobs of solder on the tops of them. Clean the board again. Test... Profit
Total time including additional swearing, re-cleaning... re-re-cleaning and re-fitting.. about 30 minutes and two strong coffees.
The replacement USB plugs are readily available on ebay typically around the £2 ($3) mark, but there are several different styles, and they are different, so make sure you use the correct one for your board.
Now back to your question... why does your battery not charge when you tack the wires to it... simple... it is trying its best not to explode. The USB port provides 5V, but the battery needs between 2.8 and 4.2 vots.. depending on its current state of charge, and this is what the charge controller chip within the phone provides. Anything else and the protection circuit kicks in.
I suggest if you don't fancy repairing the USB plug yourself, you get one of those cheap "universal" usb phone chargers from China, they cost about the same as the replacement USB plug, but are (marginally) less likely to blow up your battery.
itsthatidiotagain said:
Now back to your question... why does your battery not charge when you tack the wires to it... simple... it is trying its best not to explode. The USB port provides 5V, but the battery needs between 2.8 and 4.2 vots.. depending on its current state of charge, and this is what the charge controller chip within the phone provides. Anything else and the protection circuit kicks in.
I suggest if you don't fancy repairing the USB plug yourself, you get one of those cheap "universal" usb phone chargers from China, they cost about the same as the replacement USB plug, but are (marginally) less likely to blow up your battery.
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Click to collapse
Good description of the soldering job, the samsung pocket neo is very small but I look forward to having a go at fixing it properly one day, I dont yet have a magnifying glass or solder sucker, but I want to get them. Without these tools the job would be near impossible.
Little update: the phone is charging, I have disconected it and it holds its charge nicely, the internal software just doesn't register the trickle charge it is recieving, I have loads of old chargers and new usb cables and my old second hand phones micro usb port is way too damaged to work anymore with any charger. I use it as a modem principally, so it is connected every day and providing wifi to multiple devices and has no problems with over heating. Now nearly two months have passed and it works fine. Using this method it is possible to completely remove the battery as well. The phone is running directly off the 5 volt power with no ill effects.
It would be convienient to connect it directly to a pc in usb debug mode occasionally, and this is a very good reason for eventually fixing the usb plug.:good: