Tear Down of the 2AA Defiant light - Question about driver

Interesting information Would you please provide a link to this light you speak of?

LOLOL

Anybody want to hazard a guess about the driver?

d1

I wonder if the high and low are controlled by the resistors and if I could figure out which one is in the high circuit, I might remove it for a brighter high, with a Nichia 219 or XM-L. From the photo, anyone got any ideas??

Looks like those two 1R5 resistors are the sense resistors. They look to be wired in parallel, but can’t tell for sure. Probably does PWM for low mode.

How do I find out for sure. Is there a way to test?

You probably don’t have a meter good enough reliably to check low resistance values, so look at the pads on those resistors with a magnifier. If you can see that they are connected together at each end, then the resistors are in parallel.

Or you can try metering across the resistors. Short the probes together to get your zero-resistance value. The measure across the resistors and subtract that value. something around 0.8 ohms means they are paralleled.

I picked up a two-pack last night for $9.88…they threw them in the wrong bin! Very impressive lights for $5!! What would happen if it was dedomed? More throw, warmer tint?

They had these marked down to $7.98 at my HD.

Even better! Very impressive for a $4 light!!

I’d guess the resistors are in parallel, and the medium mode is done via PWM. While in Medium mode, wave something shiny like a screwdriver tip in front of the light. If the motion appears smooth, it’s not PWM. If you see 20 screwdriver tips all at the same time, it’s PWM.

Or you’ve been drinking too many screwdrivers… :party:

Precisely, and I recommend not waving screwdrivers around while drinking screwdrivers. Someone could lose an eye… plus you’ll look really stupid in the flashlight aisle at HD. :smiley:

Meh… you got two…

I’ve got two of a few things, and just fine and dandy with keeping them all in pairs :wink:

Maybe based on somthing along the lines of the PAM2805? Similar layout, same modes. Vref would be 0.095V, however, which would put the LED current on high at only 125mA, so clearly it’s a different chip.

Link to PAM2805 eval board document: http://www.diodes.com/\_files/evbd/PAM2805%20User%20Guide.pdf

Has anyone done a simple ‘dedome only’ on these? How did you like it? The tint on one of mine is spotty…changes across the beam. I thought a dedome might even it out. Help me out fellow BLFers!

The phosphor is deposited on the dome—dedoming will even out tint variation in the beam if you need or want a blue light.

I just read here that it’s actually not a remote-phosphor in the sense that I thought. Shows how much I know!
So I’m not sure what this LED would do when dedomed. Only one way to find out :smiley:

Thanks Slim, I keep reading that a dedome will warm the tint some, is this emitter different?

Is this the light your talking about? Did the light contain XB-D or XT-E’s? Wondering, because it may be a cheap way to put warmer emitters this light and in other in cheap lights.

http://www.homedepot.com/p/Cree-9-5-Watt-60W-A19-Warm-White-2700K-Dimmable-LED-Light-Bulb-1-Pack-BA19-08027OMF-12DE26-1U110/203991774#.Ucs20py0Qil

This little rascal with its ‘lowly’ XTE emitter has to be the brightest 120 lumens I’ve ever come across especially on strobe. It really smarts the peepers. Maybe it’s the particular OP reflector and/or the nature of the XTE itself but whatever it is it’s surprisingly no slouch. I’m even tempted to dedome an XTE and see what’s what.