A high-power LED torch using a single AA-battery

Step 5 A quick test...

If you have a 22uH inductor handy, you can test your circuit by connecting one end of the coil to B+ and the other end to the 'hook' left in Step (4).

Touch B- to the wires at the center of the small perfboard and the LEDs should all light up. SUCCESS!

On to the the final assembly bits now.

Comments

[joinaqd]

i have 2 questions:

1.) What colors are the band markings?

2.) If i have ferrite, how many turns would be needed to run this thing?

[Sandivar]

Great circuit, and I look forward to building it just as soon as I can buy the required parts.

However, I do have a question:  You use a 22 uH inductor to test the circuit; why wouldn't you just use the same 22uH inductor wired into the circuit and skip wrapping the wire around the battery?

(And where can I buy some of those types of inductors, by the way?)

[qs]

Any inductor of the correct value will work in this circuit, but inductors are not nearly as common or cheap as other electronic components - that is why I try to come up with home-made solutions for them.

One source I've used is eBay - there are a few Asian sources, like this one which has them at about 10c apiece.