Technical investigation of the XL100

As a tech geek I couldn't resist investigating my new MagLite XL100 as much as I could without disassembling it.

I found that from the bottom of the pill it looks very much like the Rebel MiniMag but not the Luxeon. The top side with the LED too but with the writing -091 instead of the -090 on the MM.

I also discovered that the pill only has two electrical connections to it - the power. This means that it's the tail cap doing the power switching. I believe this is also the case for the low PWM frequency (though upped a little from the MM) since the buck/boost regulator can't keep up with higher frequencies. An alternative would have been 3 wires - two for power and one for signal when the LED should be on.

Try connecting a (low cost) speaker or headphones to the top of the battery carrier while holding the bottom to the tail cap and operate it. Some quite interesting sounds it make. Especially with partially drained batteries since there will also be a slight amount of (almost) unnoticeable PWM regulation on full power. Nitelite or power adjusting on Dim is particular interesting and melodic.

Finally: Has anyone dissected an XL100 yet? Disassembled the pill and tailcap?
I won't do it with mine as they're quite expensive here compared to US (but still a need to have for a geek ).

Forgot one thing:

If turning on the XL100 in say strobe and then screwing out the tail cap and then back in the light will be turned off.
However when you turn it on it'll switch to strobe within 1/2 a second or so.

Then wonder: Is it kept in memory because of a "super" capacitor or eeprom/flash? Or just a regular capacitor and I put it in too fast. And what about the dim setting and to on? As long as there's batteries in the XL100 there's a current draw on the batteries (because of the soft button). Haven't measured how much though.

Perhaps I'll try to put it to a specific mode and level. Say strobe at quite low, remove the tail cap for the night and then have a look in the morning to see if it still remembers mode and level. Then we can at least tell its not just short memory resulting from an ordinary capacitor.

Sounds pretty much like I said in this post.

Missed that post.
However I can continue this thread with a bit of additional information.

Before going to bed I put it to dim low frequency strobe and while it was turned on I removed the tail cap and batteries for the night. Tail cap has been without power for around 8-9 hours.
This morning I put thing back together and it remained off. However when turning it on it started out in the dim mode I left it and after 1/2 second or so it returned to the dim slow strobe in which it was left.

Not really reassuring from a technical point. It's probably done by writing to eeprom/flash. And writing each time you make a f*rt is IMHO not a very smart design. But guess we'll only know for sure until someone disassembles his tail cap so we can have a look inside.