Super Regulated Flashlight

Last week Lambda posted this in the Modified Light BST Forum. The idea that a battery operated light would be putting out MORE light at the end of battery life rather than at the beginning, was so unbelieveable that I had to buy it just to prove it to myself!

Well, here's my runtime plot!


Lambda wasn't kidding....I measured about a 12Fc increase in the light output at the end of battery life vs. the start of the test. I measured a runtime of about 4.5 hours compaired to Lambda's 6.5 hours....which is probably due differences in batteries. I used Everactive (cheap Wal Mart batteries) and he used Energizers. Before you guys start hounding Lambda about how this pill works, I need to point out that Lambda told me that the pill was put together by ArcMania!

Here is my measure of the light output of the Super Regulated Flashlight vs other modified flashlights:

Super Regulated Flashlight 2xAA 170Fc 4.5-6.5 Hours
MadMax+ 2xAA 340Fc 1.25 Hours
FireFly 1x123 250Fc 1.25 Hours
MiniMiniMag 1xAA 180Fc 2 Hours


Notice the rule of flashlights at work! To increase the runtime of a flashlight, either the size of the battery need to increased or the light output of the flashlight needs to be decreased. The Super Regulating Pill drives the LS LED only to 170Fc but does it for 4.5-6.5 hours!

By the way, the concept of measuring the runtime at the 50% brightness level, does not work with this pill! /ubbthreads/images/graemlins/eek.gif


ADDED....

At this point in time, this is a one of a kind flsahlight.

Wow that is some amazing runtime, not to mention the fact that it outputs a bit more in brightness towards the end of the batteries life. That's one of those gotta see it for yourself or don't beleive it things.

I hope Lambda & Arcmania do a run of them. I'd definitely be interested.

Hey Lambda, do you think that's a possibility after the holidays? A run of these SRFs?

txs

That is weird, but i think the KL2 exhibits the same behaviour too. Id love to know why they act like this. Any of the electronics gurus care to enlighten me?

Here's Roy's plot for the KL3/3x123 showing a rise over 7+ hours.



Brightnorm

oh, boy.

you have my undivided attention.

i am happy with a luxeon putting out about 200 lux, and prefer longer runtimes. this is getting pretty close to ideal for me.

keep us posted!!!

Bob

In designing a switching regulator with a "constant current" output it is easy enough to bias the setpoint with the input voltage in such a way that the slope of the output current vs input voltage is upwards or downswards as the input voltage declines.

Thanks Doug, i think i understood that. So the regulator workes even harder as the batteries fade, hence the increase in brightness and the cliff-like drop out of regulation?

Yep.