[Long] White LED lighting modules - Want one?

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Greetings Y2K preppers... OddOne here, back on the attack yet again. And yes, again I speak of the white LED.


As some of you know, I coordinated a bulk-purchase of white LEDs in quantity direct from the manufacturer a couple months ago. Everyone involved has long since receive their part of the purchase and I imagine that by now some folks have cooked up a few novel uses for them. The whole process went rather smoothly, despite the fact that money-up-front was involved and nobody that participated knows me from Adam in real life.


Most of these same folks are aware of my own experiments with white LEDs. This is the subject of my post. I created a white-LED lighting module that uses 18 of them in an array. It's remarkably efficient, drawing less than two watts (@ 12VDC) at maximum brightness and as little as a quarter-watt when dimmed down. Light output is around 72 candela, which translates to about the same light generated by a 40-watt bulb for the same surface area. The module only throws light at one point, though, unlike the 40-watt bulb, which puts the same surface-measured level of light out in all directions.


And now, the point of the post...


I am almost to the point where I can offer the modules, ready to use in your projects, for sale. At $99.95 (US), they are not cheap. (When you think of it, 18 LEDs @ $1.60 each, ACTUAL PER-LED COST IN 1,000 QTY. FROM THE MANUFACTURER, means that the module uses thirty dollars' worth of LEDs alone. These modules can NOT be manufactured with the quality I insist upon cheaply enough to push the price down for small-quantity purchases.)


The module contains an onboard regulator to protect the LEDs from supply voltage changes, and the LEDs are driven in six groups of three each by power MOSFET transistors by a variable-duty-cycle-and-clock-rate driver circuit (pulse-width modulated) to permit turn-of-the-knob control over brightness. The 6x3 array drive makes the light output more balanced across the LEDs as well. The regulator holds the per-LED voltage to about 3.7 VDC with a supply of up to 20VDC in my tests. They are intended for 12-13.8 VDC supply at about 150 mA maximum. Parts are name-brand, top quality new components. No surplus or seconds. The prototype uses parts from manufacturers like Harris Semiconductor, Xicon, SGS-Thompson, and others. The PC boards will be professionally produced, double-sided affairs with plated-through holes on top-quality FR4 PC board material. The LEDs themselves are each mounted with a 1/4" plastic standoff to make their mounting more rigid and secure and make it less easy to bend their leads and misalign them as a result.


A website with pictures of the prototype and more specific information is located here:


The production model will sport a ribbon-cable connection from the LED array board to the rest of the module, which permits remotely locating the array from the rest of the module. (Simply insert an extension cable in betwixt the two to increase the separation.) This is not shown on the prototype pictures.


The module will come as shown in the picture, less the battery holder of course. You'll need to supply the use for it and case to house it. It's pretty ruggedly built though. (Actually, it's a pretty tough little s.o.b. I use the prototype as a handheld flashlight without any sort of case.) Hookup is simply a matter of connecting the 12V source to the two power leads and twisting the brightness/power switch knob.


I am now collecting a list of people that want to obtain one or more modules. If there is enough interest I'll secure the funding and start production. Folks that jump on the modules in advance would be given the chance to pre-purchase modules when production begins and these folks will receive theirs first. If you would like to purchase one when they become available, please send me E-mail to that effect with your name, address, and how you'd prefer to pay for them when the time comes. If you have already stated such interest I'll be contacting you via E-mail shortly to see if you're still interested. (I have to compile statistics on how many I can sell before I can secure the funding for the project. Stupid and annoying, I know, but that's how the banks like to do things...)


I will be able to spring slight discounts for quantity purchases. However, since the parts costs for these modules are high, I can't offer too much of a discount unless we're talking LARGE quantities. (By 'large' I mean 100+ at a time; hello dealers!)


The modules will initially be hand-assembled and tested. I'll be supervising that process directly. (I can solder to mil-spec, so solder joint quality isn't going to be a problem. I worked on an electronics assembly line as the "do-anything" man, meaning I could take any position from loading the PC board blanks to testing them as they came from the wave-soldering machine, and did most every position on the line at least once, for a while as well so I do have real-life experience in the area.) If the demand warrants investing in a wave-soldering machine I'll get one, but since these jokers cost 5-, 6-, sometimes 7-digits, there'll need to be a LOT of demand.


A side note: PC boards alone may not be available initially. It all will depend on the demand. If you want the bare PC boards, please let me know. Enough demand and I'll add additional PC boards to the order from the PC board replicator to compensate. If I do, they will cost $29.95 for the set of four. (One is the PWM driver, two hold the six power MOSFET switching transistors, and the last is the LED array board. A complete parts list for the module will be included; you can pick the parts up in one stop by mail-ordering them all from Mouser Electronics, which is my principal supplier. The white LEDs will be tricky to get at a reasonable cost. Perhaps when I coordinate another bulk-buy you can get in on that to get your 18.)


For comparison purposes, a few other places selling white LED modules are:

Jade Mountain, Inc. (Note the prices for their ready-to-use modules. My module is similar to their "18LED Sunspot (DC5966)" that they list for $98.00. Their unit doesn't include brightness control or onboard regulation, though.)

Alternative Energy Engineering (Skip down to their Super Nova fixture. They ask $120 for it. In its favor, it comes with 18 LEDs mounted in its own fixture. But again, no regulation to protect the appallingly expensive LEDs and no dimmer capability.)

HDS Systems (Their Action Light, which looks to be similar to my module but is enclosed in an aluminum case. They want $299 for it! Well, at least they throw in a battery and this model DOES have a basic three-setting brightness control. Hit their FAQ page for pictures of white LED lighting compared to that from a flashlight.)


There are likely other suppliers of modules of various descriptions and capacities...


Well, that covers it. Apologies go out in advance to anyone annoyed by the commercial aspect of my post, but since it's thanks to the TB2K forum folks that I even have the chance to do this, I'm offering it here first.


-- OddOne (mocklamer@geocities.com), May 26, 1999


Although there were lots of room for problems, I want to state that he kept his end of the bargain 100+%.

There were two situations that could have become problems, one of our guy's check didn't get to OddOne so he was listed as a no-show. The check was later returned by the USPS, we think the USPS got confused.

The other situation was mine. One of my "Sites" has an problem address and the package was delayed a week. I have the LEDs and have sent a few out to guys who are working with me to refine an "anyone can build it" flashlight.

I am pleased at how the deal came off and wouldn't hesitate to send a check to OddOne next time.

-- cory (kiyoinc@ibm.XOUT.net), May 26, 1999.

I'll second Cory's statement. I ordered a 100 LEDs and received the package priority mail. The OddOne is a man of his word and offers unusually good help to the novice who asks...I know, I'm about as novice as it gets when it comes to electronic devices...


-- brett45 (brett45@bigfoot.com), May 26, 1999.

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