|Has your phone or iPod ever died when you needed it the most?
That's why I designed a quick little battery charger for your
electronics! Just plug your device into its USB port, turn it
on, and you're all set! Best yet, it all fits in an Altoids gum
tin!| The USB PlanLots of electronics are powered from a USB
cable, so I figured that a powered USB port would be the most
useful power source. I used a voltmeter to measure the voltage
on each of the pins on my iPod AC Adapter, and wound up with
+5.16V on the V+ pin, +2.06V on the D- pin, and +2.76V on the D+
pin. I'm using a 7805 voltage regulator to get +5V for V+, and
am using two resistors for each data pin. I calculated the
resistor values to minimize current loss (as not much current
needs to go to each data pin). Here's the schematic: USB Charger
Kit P/N 2136761 Parts You Will Need USB Project AssemblyFor
simplicity, I decided to just twist the leads together, as the
circuit is pretty simple. You may want to solder them into a
prototyping board for durabi