Step 1: Introduction
The basic idea here is to charge my Nano via USB while in the car. The total project cost for me was Free-99. I had all the spare wiring and cables because I never throw anything electronic away. I did however build another one for a shade under $8 bucks. I mean thats not terrible for a car charger for your iPod and other USB chargeable devices. Plus its fun to DIY.
Typically, your USB port provides 5v of power through a single wire in a 4 pin USB cable. The normal operating voltage for most USB devices is between 4.75 V and 5.25 V. Ok great we understand that, but now how to get 5v from the 12 volt source (your car)? I stumbled upon this idea by accident, literally, I tripped over my wall charger for my Nextel-Motorola i870 and noticed that the adapter has an output of 5v to charge the phone. So, I went outside to my car to check the output voltage of my car charger, it was unmarked, so off to the Wal-Mart that is across the street I went to pick up a multi-tester. Upon testing the voltage output of my car charger I was astonished to see that sure enough the output was 5.15v well within the range to charge the iPod.
Read that last part again, I verified the voltage on a voltmeter. I also tested several other car adapters I had laying around, and the output voltages varied greatly, from 3v to 14v. So unless you are positive of the output voltage dont just splice away expect to get the right voltage to your iPod. (on a side note I also constructed a Firewire wire alternative from the aforementioned 14v car charger, and a tutorial for this one is coming soon). After verifying that the voltage was within normal USB operating range I used a USB extension cable to get a female USB plug. The next steps follow logically, splice USB female end to car adapter wires, seal, test voltage, go plug in. Direction and some pics follow.
Step 2: Parts and Equipment List
- Motorola Car Charger for i205 i305 i315 i325 i530 i710 i720 i730 i733 i740 i830 i860 i870 cell phones.
Any car charger that has an output of 4.75v to 5.25v. (Note: I also used a Belkin Mobile Power Cord (#F8V7078-E-MK, $7.68 at Wal-Mart) which has an output of about 5.8v and it works fine as well, but to be safe, stay in the 5v range so you dont burn out the voltage regulator in your iPod. Also, be sure that your car charger has some sort of fuse protection)
-USB extension cable USB A/A M/F (you should have a least one of these somewhere)
Some sort of USB connection to your iPod I use an Apple iPod Dock Connector to FireWire and USB 2.0 Cable for everything that I do with my iPod, as its the only dock connector I own.
Soldering iron, Solder, heat-shrink tubing
A pair of cable strippers