The input power source could be rechargeable AA batteries. Let’s make an environment friendly 12V/130mA power supply!
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Signing UpStep 1: Design the Prototype
First I etched four PCBs for the prototype using a PCB design software and some other tools. The PCBs are very small (4cmX2cm) because components need to be solder as close as to the IC; because of the performance issues. I made ground copper track as wide as possible.
Now my prototype works fine and I decided to make the PCB in large quantity. I did some changes and sent my PCB file to a local PCB production company and first I got 100 pieces of PCBs. The PCBs are in good quality with solder spots and copper shield; easy to solder.




































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Also, don't need to simply look for 12V lights that use under 130ma.... you can also get any old 12V LED or incandescent and use resistors to keep power draw down to within levels of the LT chip's spec. So if you have a 150ma LED light, you can get the power draw down to ~100ma using an 80R (ohm) resistor. A chip like this may be rated to 130ma, but that's under ideal conditions and temperature... when it gets hot, it's not 130ma-capable anymore. Datasheets can seem to conflict in some respects.
Although this chip will produce 12v, from a single AA cell there is NO WAY you will get 130ma 12V. Wire up 4 or even 6 AA's in parallel. The fewer parallel cells you use, the more likely the batteries will get very hot because you will be pulling a lot of juice from them. Use your judgement and don't leave this running unattended unless you know what you are doing.