Figure 1
Making things is fun! Making an iPhone charger which uses two 1,5V AA batteries is actually easy! At the heart of this small project, there is a DC-DC step-up (boost) converter.
The main part is packed in an IC and only a few external components are necessary to build it, to be able to pump a little charge into your iPhone when there are no wall sockets around.
The whole stuff can be bought as a kit from Adafruit, including all the necessary components and a PCB. If you are in the US and want to save yourself some trouble getting all the components by yourself, -especially the IC and the PCB- then you might want to consider buying the kit from Adafruit.
Adafruit MintyBoost Kit – v3.0
However if you live outside the US, the additional international shipping costs might render this idea not worth to follow.
To save costs, I’ve decided to build it myself from the parts. All the components were relatively easy to come by from local electrical stores expect the IC and the PCB. However thanks to the generosity of the European Linear Technology sales office in Munich I could get two samples of the LT1302 IC for FREE!!! (Big thanks goes to Torsten Lessnau!) After this the only remaining item was the PCB. I went for the easy solution, by choosing a perfboard (stripboard, prototyping PCB). I only had to cut a few copper strips and add some jumper wires to make a replacement PCB for the project.
The datasheet for the LT1302 can be found here.
The circuit diagram to build this project can be found here.
The part list (version 3.0) is here.
The fully assembled and working project can be seen in figure 1.
Thanks Adafruit! Thanks Linear Technology!
Happy Charging! 🙂
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