Core Electronics Forum

Suitable parts for a mini torch AA battery size

I’ve have a small retail pocket torch that runs a single bright white LED off a single AA battery. The overall housing is too big to embed inside a piece of timber work that I’m making without making the timber surround very chunky. So I’m looking for the similar components to make my own small board and internal switch inside a cavity the diameter of a AA battery or just a bit bigger (<20mm). I’ll need a Super Bright White, a small push button and a resistor. I have some left over strip board I can cut up to make a small disk onto which I can solder the switch, LED, push button, resistor and a couple of wires. If this set up works I’ll be making a few dozen. Will a 5mm Superbright LED with a 3FV work ok on a 1.5V battery or will it be too dim?
Do you have some dimensions on the pushbutton also in the products list?

Hi Andrew,

That might work, but super bright LEDs will often have forward voltages of around 3.2V, so it probably won’t be super bright without a higher voltage supply. You could use some coin cells instead. I’d suggest taking a read of our All About LEDs Tutorial:

You might also like something like this:

We’ve got a really wide range of pushbuttons, all the way from little SMD pushbuttons up to huge novelty dome ones. Was there one, in particular, you were looking at?

Regards,
Oliver
Support | Core Electronics

Oliver,
Thanks, I’ll read those two links. The second one (1W Cool White) needs a heat sink, on a AA battery?? There will be no air circulation around the embedded torch assembly.
The push button that would be suitable would be a PCB mount , pin preferably not surface mount, if possible. It must be an on/off. It will be hidden inside the timber work and the timber frame I’m making will be the action presser on the top of the battery, so looks don’t matter at all.
The stack order of components will be from the top: battery, contact plate, push button, strip board, resistor and then LED at the bottom.
I found this product SKU: ADA1683 but it is out of stock. If you have something similar that would be good, I’d like to get this sorted and ordered tomorrow if possible.

Hi Andrew,

The LED I suggested you consider actually already has a heatsink on it - it’s mounted on an aluminium plate.

That pushbutton comes from Adafruit (who are based in New York) so it’s been difficult to get stock out of them due to the COVID-19 pandemic. I’d suggest taking a look at these as an alternative:

Regards,
Oliver
Support | Core Electronics

Oliver,
Thanks for that clarification on the 3W heatsink.
The pushbutton you mentioned last is a momentary reset?
I need a latch-on/off switch. The size and power rating would be ideal if it is a latch-on/off?

I’m guessing this one is a momentary as well ?
SKU: COM-00097
I may need to make a mechanical latch if that is the case.

Andrew

Hi Andrew,

That’s correct, both the switches are momentary, below I’ve linked the smallest SPDT switch that we provide for you.

30V @ 200 mA

Bryce
Core Electronics | Support

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No worries, thanks for letting me know.
I managed to find a switch that I included in a completed order and it is totally suitable for what I need. ADA3870
Thank for your help the feedback online.
Regards
Andrew Warr

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