evil.genius.todd
Newly Enlightened
I'm clearly in way over my head.
I just stumbled upon this place while searching for SPICE models of the new Luxeon K2's. omg... You guys are as obsessed about lighting and "doing it right" as I am.
BACKGROUND:
I love my mountain bike. So much so that I ride it year round. Here in Finland it gets dark in the winter....very very dark. In the northern parts the sun never bothers to come up for a large chunk of the winter. Down here in Tampere it is only up for a few hours in the dead of winter. The rest of the day it's pitch black. Everyone who rides a bike is required by law to have some form of illumination whenever it's dark. It's not so much so you can see anything, but more so others(like pedestrians and cars) can see you coming. Last winter I spent more time than I care to admit cursing my Black Diamond Moonlight. It is a fine, first generation LED light for it's original intended purposes(climbing, hiking, caving). But on a bike, at 50+ Kph, in the snow it's just uselessly underpowered.
So this year I decided I would have to get a better light, before the snow starts falling. I hit up several UK bike shops for various lighting solutions. And I managed to find all manner of very impressive looking solutions. Some HID, some Halogen, and Several Luxeon LED lights. But I was totally unimpressed with the cost/light ratio. Why should I pay 300€+ for a light with two $5 LED's in it? Are batteries, a pretty case, and a few circuits really worth that much? Heck no. Second I know the Luxeons are bright(50 or more times brighter than conventional white 5mm LED's).But only 2. Why even bother? I'm sure they are fine for warning off others and working close up. But that is simply not going to cut it for my purposes.
I want a real light assembly for my bike. I want to be able to read a newspaper in it at 40 meters. I want to burn the retinas out of any poor soul foolish enough to look directly at me. I want to disrupt air traffic. Is that to much to ask for? LOL
o.k. maybe not that bright. But two original Luxeons are not in my plan.
What I want:
I would like to build a light assembly for the handle bars on my bike. I've had several false starts for even a preliminary design layout. But with out knowing some of the basic design requirements for the Luxeons(and other LED's under consideration). Each attempt has felt like a waste of time. I can't even really start to design the look and configuration without having the answer to several basic questions:
1) Luxeons, like all LED's, require some form of current limiting if they are to be run at or near their max cont. rating, or they will simply burn themselves up. I'm aware that a current limiting resistor(s) is a terribly inefficient way to limit current. So a current limiting power supply is the way to go. Which type or model is the most efficient?(for a single LED just to simplify the answer)
2) In addition to current limiting, is some form of voltage regulation(Linear/SMPS) necessary? Or is current regulation the only thing that matters to the circuit?(I'm guessing they care quite a bit about voltage. But I don't really understand current regulation, or it's implications on an electrical circuit)
3) Does anyone here know where I can get a decent SPICE model of some of the new LED's. Specifically those from Edison, Lamina, and Phillips? Or heck, where I can find a decent SPICE model source in general?
My apologies in advance if any of these questions are just plain stupid
I just stumbled upon this place while searching for SPICE models of the new Luxeon K2's. omg... You guys are as obsessed about lighting and "doing it right" as I am.
BACKGROUND:
I love my mountain bike. So much so that I ride it year round. Here in Finland it gets dark in the winter....very very dark. In the northern parts the sun never bothers to come up for a large chunk of the winter. Down here in Tampere it is only up for a few hours in the dead of winter. The rest of the day it's pitch black. Everyone who rides a bike is required by law to have some form of illumination whenever it's dark. It's not so much so you can see anything, but more so others(like pedestrians and cars) can see you coming. Last winter I spent more time than I care to admit cursing my Black Diamond Moonlight. It is a fine, first generation LED light for it's original intended purposes(climbing, hiking, caving). But on a bike, at 50+ Kph, in the snow it's just uselessly underpowered.
So this year I decided I would have to get a better light, before the snow starts falling. I hit up several UK bike shops for various lighting solutions. And I managed to find all manner of very impressive looking solutions. Some HID, some Halogen, and Several Luxeon LED lights. But I was totally unimpressed with the cost/light ratio. Why should I pay 300€+ for a light with two $5 LED's in it? Are batteries, a pretty case, and a few circuits really worth that much? Heck no. Second I know the Luxeons are bright(50 or more times brighter than conventional white 5mm LED's).But only 2. Why even bother? I'm sure they are fine for warning off others and working close up. But that is simply not going to cut it for my purposes.
I want a real light assembly for my bike. I want to be able to read a newspaper in it at 40 meters. I want to burn the retinas out of any poor soul foolish enough to look directly at me. I want to disrupt air traffic. Is that to much to ask for? LOL
o.k. maybe not that bright. But two original Luxeons are not in my plan.
What I want:
I would like to build a light assembly for the handle bars on my bike. I've had several false starts for even a preliminary design layout. But with out knowing some of the basic design requirements for the Luxeons(and other LED's under consideration). Each attempt has felt like a waste of time. I can't even really start to design the look and configuration without having the answer to several basic questions:
1) Luxeons, like all LED's, require some form of current limiting if they are to be run at or near their max cont. rating, or they will simply burn themselves up. I'm aware that a current limiting resistor(s) is a terribly inefficient way to limit current. So a current limiting power supply is the way to go. Which type or model is the most efficient?(for a single LED just to simplify the answer)
2) In addition to current limiting, is some form of voltage regulation(Linear/SMPS) necessary? Or is current regulation the only thing that matters to the circuit?(I'm guessing they care quite a bit about voltage. But I don't really understand current regulation, or it's implications on an electrical circuit)
3) Does anyone here know where I can get a decent SPICE model of some of the new LED's. Specifically those from Edison, Lamina, and Phillips? Or heck, where I can find a decent SPICE model source in general?
My apologies in advance if any of these questions are just plain stupid
. I'm hoping one of the mods will move it.
