What kind of driver to use with a 2-mode switch?

fyrstormer

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I got my hands on a Surefire L1, and its output is predictably underwhelming. I've already got the driver removed from the body of the light, and upon inspection...I can't tell whether it's a constant-voltage driver or a constant-current driver. I think it's a constant-voltage driver, but that's based purely on my assumption that a constant-current driver would be less-than-ideal for use with a 2-mode resistive switch. If I understand correctly, even though a CC driver couldn't force the battery to supply it with the power it requires, it would still boost its output voltage as much as it could in a vain attempt to deliver the specified current, inflicting unnecessary strain on itself whenever it's operating in low mode. Whereas, a CV driver would just maintain the specified output voltage and deliver whatever current is allowed by the resistor in the 2-mode switch.

Is this an accurate assessment? If not, what am I misunderstanding?

So anyway, I'm contemplating installing a 1-amp driver in this thing to give it more punch on high, and changing the low-mode resistor in the switch to keep the low mode dim enough for use at close-range. I know I'm not the only person to do this, but I haven't had much luck finding current, relevant information for this mod -- probably because the L1 was discontinued about 6 years ago. If it turns out a CC driver is the way to go, I can find that easily enough at the Sandwich Shoppe, but if I need to use a CV driver I don't know where to find one. Can anyone recommend a 1-amp driver that would be suitable for use in the L1?
 
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id30209

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First question, how did you remove it?
Second, it's constant voltage driver. I have swapped led and it draws around 1.4A with stock driver on high. Almost 600lm instead of ~100lm with old emitter?
To install upgraded driver is my next mission but i'm affraid not to destroy it while removing it.
 

fyrstormer

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The driver is held in place by four plastic tabs. I pried those plastic tabs out of the groove they were locked into, and the driver pushed out. I think I will re-wire it to be a "dumb" battery tube, with no driver at all, so I can put the new driver in the head of the flashlight, as is common nowadays.

There is no way my L1 Lumamax is pushing 1.4 amps through the emitter. It is rated at 65 lumens on high, and even the Cree XR-E emitter could produce more than 65 lumens if it had 1.4 amps to work with.

Where can I buy a constant-voltage driver nowadays? All the single-mode drivers I can find are constant-current.
 
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id30209

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So we don't have the same L1. Mine is older, 50lm. And maybe i said to much but for sure it delivers 1A and a bit more but with NEW emitter only.
I have tried Nanjg single mode driver with dual stage and works perfect. Even HF17F and Dragon successfully runs on dual stage.
 

fyrstormer

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Yes, that is my goal. But if I understand the operation of a constant-current driver correctly, limiting its input power with a resistor (which is how a 2-stage switch works) will cause the driver to strain and/or drop out of regulation.
 

id30209

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I think experts will answer much better. I'm pretty much big noob in this area. I know only basics. Just wanted to share my experience with L1. I'm away from home now but when i get back i can send you some videos of testing each driver with dual stage.
 

fyrstormer

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Thanks. I was eyeing the GD driver before, and it continues to look like the best option even though it's not a constant-voltage driver. I might just have to accept that whatever driver I pick will be forced to drop out-of-regulation when the power switch is in low mode.
 
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