This is sweet, I’m gonna make one right now so I can charge my MP3 player on the go! Also w00t first post!

You should make a backup battery for the zire 71

Slick. And now for a case idea. To go along with the Minty MP3 (http://www.hackaday.com/entry/1234000607027290/) use an Altiod case. Not sure if it’s big enough, but I was thinking maybe the Gum cases. (Go to http://www.clorders.com/altoids/shoppe.html and scroll down to see what I mean.)

A resistor and zener diode make an extremely poor voltage regulator. I wouldn’t trust it on anything of value. Do like steven already suggested and use a real voltage regulator like a lm7805. You can buy them off a peg at Radio Shack, so it’s not like they are hard to get. If you use a 7805, you won’t need a zener.

Also, the zener does not drop 0.6V like mr. bee suggested. Forward biased diodes drop about 0.6V, but zener diodes are used in the reverse bias mode, where they drop the zener voltage, in this case 5.1v. That’s the whole point, to use the 5.1v drop as your regulated voltage. But like I said, it is a very poorly regulated voltage and I wouldn’t trust it to power my fancy new gadgets when a real regulator costs a buck or two.

By the way, is there some sort of rule against capital letters here? It looks really stupid.

YES HERE IS A RULE AGAINST CAPITAL LETTERS!!!!!!111

It seems like it’s questionable whether this could actually charge a device. At 330 ohms, the maximum amount of current that could be flowing is (9-5.1)/330 = roughly 12mA. There are a couple things that could be done to correct this. You need to use a lower value resistor (getting a 1W resistor should help), and possibly a higher wattage zener diode. Here’s a great reference for designing a zener diode regulator: http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/zenereg.html#c2
Just plug in your desired values, and it will show you component values and required wattage. You’ll need to calculate the wattage of the resistor on your own though, but it’s just (9-5.1)^2/R = 15.21/R. In the example above, 15.21/330 will require 0.04W. A 100 ohm resistor needs to be 0.15W. If you’re using a 1/4W resistor (which I think is what is shown in the picture), it’ll get hot.

im working on a cable to go from computer usb to charge my motorola phone, ill post that up somewhere when its done, woot

I agree with those above. The ic regulator is safer. And you can sample the ic from fairchild, which makes them, and you can sample the usb adaptor from molex with a bit of searching for the right model for you. You could probably fit it all in one of the altoids gum container, if the 9volt fits. You could even add a heat sink inside the container for the ic if your so inclined.

Side note, the altoids gum container = cheapest coolest ipod shuffle case. Add a hole for your headphones, and the usb connector, with a rubber seal for the headphone hole and the tin’s case door, and its even water proof.

Only thing is, if you use one case for the shuffle, and another for the battery pack (even though the shuffle takes two aaa batteries ~_^) you might want to get three usb connectors, all female, wire two in the shuffle tin, with one connected to the shuffle and the other in a hole outwards, and the third in a hole for the battery pack. Then get a male to male A usb cable. two tins, with extra P0//3|5!!! Plus, they look like nunchucks, or better yet, sword chucks or even better, wand chucks!!!! <3 8-bit theater….

Or, you could just place the battery pack and the shuffle in a regular sized altoids tin. just add a plastic divider down the middle of the long side, and you only need the one usb female A connector, with a bit of cable.

P.S.: hackaday should add a altoids/tin channel ^_^

But don’t those chargers cost more then your average 9 volt? And they aint rechargeable, like you can get for a 9 volt. But, they could do in a pinch if its the right voltage and ampage, so buyer beware.

Very interesting hack, and EXTREMLEY well written. I really appreciate the “How it works” section, and it makes it very easy to use. I will try this before the altiods battery pack, and if that works, I will dive into that. It would be GREAT if you could either make another version of this for a firewire port, or a version to support higher voltage (ie: iPod.)

Thanks a ton, and great work..

Matt

A nine-volt is great, and a four-pack of AA batteries could be better–but how about a 6-volt lantern battery?

it would be cool if you could do this for a usb mini plug too.
if you could connect it to the male end of a usb mini plug, then you could use it for all sorts of things that have the mini usb ports as opposed to normal usb ports.

As soon as I saw “5.1 zener” I thought “bad way to go, dude”. I’ve been using 7805 since, well, since they made them. Cleanest, easiest, and cheapest way to get 5 volts. I wouldn’t hesitate to plug a 7805 regulated supply into my ‘pod.

You can also use a 7805 with 12 v, however, you may have to add some caps if you are plugging it into a cigarette lighter (to filter out engine noise). Some inline diodes (between the 12 v. and the 7805) will help with the temp…

Also note: the 7805 needs at LEAST 7 volts…

This is about the minimum circuit all right. Neat hack!

But using an integrated circuit voltage regulator has a huge advantage: it doesn’t waste nearly as much of the battery’s power, so it can deliver more to the phone/whatever. (see prev. posts about the resistor value, maximum mA, etc.) Best case, only about half of the 9V’s battery power will go the device; the rest will warm up that 330 or 100 ohm resistor, a shame. And the more power you try to get (by lowering the resistor’s resistance, like to 100 ohms) the more quickly you’ll burn thru a batt even with no phone connected.

Googling the #5 post’s suggestion of the LM7805, I soon found a shop selling a parts kit for all of $2.50 (site unkn to me; caveat emptor). It comes with a 2nd part (a ‘capacitor’) to reduce static (such as from your car’s cig lighter) that might sneak in & confuse your device’s circuitry, or leave it out so the adapter is EVEN SIMPLER than the resistor/zener circuit.

Walt says, “check it out!”

//Matt:
It would be GREAT if you could either make another version of this for a firewire port, or a version to support higher voltage (ie: iPod.)
//

The altoids battery pack IS another version of this using firewire AND ipod. Durr…

//Carl
it would be cool if you could do this for a usb mini plug too.
//
First, you can do it with any type of plug, required you use the right cables (power and ground of the connector). Hell, I can make a usb to mini 1/8 stereo jack if I wanted to.

And Second, seeing how most items that use mini usb plugs have the miniA/B male connect to it and a usb A male to connect to the computer/power/battery, this hack would already work for it. Unless you want to have a really smaller cable connector, in which case, try to get a Molex sample of the miniA/B-to-go models. They accept both mini A and mini B usb connections.

And about the caps, its easy. IF (A | a) then a, if (B | b) then b etc.

adam, how much did they cost each. And what kinda store? Military surplus or electronic? And do they have a web site ^_^ (12v batteries like that would make great model rocket ignig system power sources, along with e(lectronic)fuse cannon wire for fireworks)

so i’ve read all this stuff and i jus need a straight answer on what to buy when it comes to diodes,
this is for a reg 20gb 4g ipod
and if i used 4 AA would it be different from 1 9volt

That is neat. But in my opinion the zener diode burn an apreciated amount of power, which is not useful. I have some sugestion if you like. but the number of components would difinitely increase, but it would be much more efficient.

Awsome hack, i’m gonna try this for sure.

any possibilities that my new Shuffle will be overheated if i fall asleep with my new-made charger into it ? .

excuse my bad english .

but im from sweden, no company in the states sends packages here, it suxx .

is the voltage of the regular ipod similar to that of the shuffle or would this usb battery require some modifcation to work safely on a regular ipod?

Technically, a usb cable can carry more then 5 volts. I have been able to send 30v thru one. The USB standard requires that usb run on 5 volts. Everyone go read the new article “USB-Battery 2.0″ and check the back logs of hacks. They have a couple of 12v firewire iPod battery packs in mind.

has anyone tired to charge their ipod shuffle using this method or the other one, i have and it does not charge, i think it runs off it instead. as there is no data communcation with had.

will

I just saw this:

Product News Network, Jan 5, 2005 American Power Conversion(APC) USB Battery Extender — allows up to 60 minutes of talk time via a USB charging port. Use and charge a mobile phone. This small, compact power solution is the perfect emergency battery. Requires a USB charging cable and AAA batteries — cable sold separately. (Estimated resale price of $7.99).

A lot easier than DIY

How’d do you know which side is for the cathode and which is for the anode on the usb device? Does it matter?

heres the pic
http://img119.exs.cx/img119/8743/dsc029819eu.jpg

ok, im a newbie but i built both usb battery, this one and the onther in this site.

this one are strange. when i test withmy meter i got 5.14v, but when i try connect any device (ipaq or ipod) nothing happens.

anyone here had the same problem and know how to fix it??
thanks in advance

PC

i would sudjest to encase the usb cirtury in hot glue so it Is more stable/sturdy you do not close of the cable acces. and if you do make sure that you don’t restrict the use of the usb slot.

wouldent that drain your ipods battory in a couple of days email then anser? cus im scared to hook my ipod up to one

An excelent hack for a quick fix for ipods, laptops and many other items similar.

What you would do is hack the shuffle case so it can accomidate one of theese sets (battery included) INTERNALLY with the battery poking out a bit ala gameboy.

Pretty useless at first glance but undeniably good for keeping in your hackbox.

Found a dps-9000 external battery at 7.2 volts for my PDA. since the internal battery is 3.6v but the PS is 5 volts I am afraid to push it to 7.2. Like the use of the 7805 to get down to 5 volts which also works on my digicam.But from looking at the data sheet it looks like it needs a larger power drop then 2.2 volts. Would it in fact work at that input voltage?
Thanks

If you do not supply enough voltage to the 7805 then it will output less than 5 volts. How much less depends on the cuttent being drawn. Going by memory, when I tried it 10 years ago, the more current the bigger the voltage drop. At low current I believe it was a little over 2 volts, but at an amp it was about 3 volts. So, you need a little over 7 volts input at low cuttent and at least 8 volts for 1 amp.

i wante to mack usb charger for ipod 1G
can u help me

I built something similar, just added some capacitors to buffer voltage peaks in case they occur. My device can be used as a “Battery Pack” or as a usual charger. I don’t know why the iPod shuffle only starts charging after switching the input voltage beneath that one required by the 7805 to work correctly und back up again. Seems the Charge mode has to be activated in some way.

http://www.eighty-four.de/charger/

i have a usb2 pccard, i made a batter back to plug into it instead of an ac adapter, cause i want to be able to use it away from ac. but the power connector is bent inside or something and is intermitent, i cant trust it. my battery back is 4 nimh 1.2v batteries equaling(1.2*4) 4.8. which seemed to do fine for the device i was trying to power. so my question: can i make a usb cable that cuts off the power from the host, then connect to my batter pack to supply 4.8 volt to the device.

Thanks for the hint! Do you know if it’s necessary to permanantly have those 2.8 Volts on the D-Pin, or if a single impulse is sufficient to activate charge mode? If so, one could add a switch to toggle between “Battery Pack” and “Charge” mode?

use an im7805 regulator (radioshack Catalog #: 276-1770)for $1.59. It takes the place of the diode and resistor and takes up to 35 volts.

i added an FM transmitter and stuck everything into a case. works great for my shuffle and even cd player

you are certainly not speaking about the ipod shuffle! There is no such information on it, and i doubt that it can be powered with more than +5V without being damaged immediately. try it out and post pics, and not just fairy tales…

Response to post #82 Tom. I thought you had to have both pull-up and pull-down resistors on the d- and d+ lines. Are you leaving the d+ line float? Does your Ipod charge at the 100ma or the 500ma rate?

Universal Serial Bus (USB)

So I need to make one of these, but need to use 4 AA batteries. I know that using a 7805 won’t work because 4 AA do not equal the 7 volts required for the 7805 to successfuly regulate down to 5volts.

What should I use instead of the 7805 to get the 6 volts generated by the 4 AA down to 5 volts? Silicon diode? Something else?

Hi !
I would like to learn how to make USB cable which It gets electric from PC and turn it Hz (frequenty)

there’s no way you can raise the voltage from 5v to 12v using a simple resistive circuit. connect extra batteries.