theatrus
100-mile-commuter
Buying an LED lighting fixture is easy, but its not fun. As such, I've decided to do a start to finish project to design a replacement for my current T5 lighting setup using no "kits" or other pre-fabricated bits (excepting AC/DC power supplies, because those are hard to design).
My intent is to produce a monolithic "puck" LED emitter board containing a series of emitters arranged into channels on one metal-core single layer PCB, in addition to a driver and controller arrangement.
The board is designed to fit in the footprint of an 80mm fan, which will be connected via threaded rods through the heatsink to the emitter board. The drivers and controller will then be stacked above the fan on the same footprint, forming a wide pendant light (way less sexy than Kessil).
The above image shows the heatsink stock (Heatsinkusa.com 4" serated) cut to size, along with a very dirty old fan as reference of the desired shape. Any heatsink could be used here - this is a bit oversized for good measure.
The design packs a large number of LED positions on the single layer metal core emitter board (not all have to be stuffed of course).
The pads and suggested LEDs are:
for a total of 38 emitters on the PCB. Emitters can be skipped by simply jumpering over the pads.
(~ 3x3in board)
Why so many LEDs? Lower currents, higher efficiency, and future flexibility. Remember, this is not a build-cost efficient fixture
A downside to the large emitter count is the inability to provide secondary-optics, focusing the light tighter than 120 degrees from the primary optic. The emitters are simply too close together to use most commercially available lenses, which feature large footprints. I intend to run these pendents very close to the water, which would not need the use of an optic.
Also integral to the board is a Microchip MCP9808 I2C temperature sensor. The sensors ground pad is brought out to one of the mounting screws, in an effort to get a good thermal path.
All connectors to the board are a series of Molex PicoLock blade-style high current flat wire-to-board connectors. I've successfully crimped the contacts, however annoying it may be, with the Engineer PA-09 which qualifies it for hobby use (as the Molex official crimping tool is $500). I've used the 10-pin and 6-pin connectors, as those are the only ones available in stock at any distributor (a downside to more unique connectors).
I have ordered prototypes (metal core prototype prices are nowhere as bad as they used to be) and stencils of the emitter board, and am continuing the design work on the driver and controller boards to sit in the stack.
Stay tuned to this thread!
My intent is to produce a monolithic "puck" LED emitter board containing a series of emitters arranged into channels on one metal-core single layer PCB, in addition to a driver and controller arrangement.
The board is designed to fit in the footprint of an 80mm fan, which will be connected via threaded rods through the heatsink to the emitter board. The drivers and controller will then be stacked above the fan on the same footprint, forming a wide pendant light (way less sexy than Kessil).
The above image shows the heatsink stock (Heatsinkusa.com 4" serated) cut to size, along with a very dirty old fan as reference of the desired shape. Any heatsink could be used here - this is a bit oversized for good measure.
The design packs a large number of LED positions on the single layer metal core emitter board (not all have to be stuffed of course).
The pads and suggested LEDs are:
- 4 Rebel UV emitters (these are very expensive, but more efficient than the popular Chinese SemiLEDs emitters. They however do not have a primary optic - more on this later)
- 6 Cree XP-G(2) White emitters (or any Cree XP package)
- 6 Cree XP-E Blue emitters (or any Cree XP package)
- 6 Osram Oslon Squre Deep Blue emitters
- 4 Osram SSL Hyper-Red
- 4 Phillips Rebel PC-Amber
- 4 Phillips Rebel Cyan
- 4 Cree XP-E Green (or any XP)
for a total of 38 emitters on the PCB. Emitters can be skipped by simply jumpering over the pads.
(~ 3x3in board)
Why so many LEDs? Lower currents, higher efficiency, and future flexibility. Remember, this is not a build-cost efficient fixture
A downside to the large emitter count is the inability to provide secondary-optics, focusing the light tighter than 120 degrees from the primary optic. The emitters are simply too close together to use most commercially available lenses, which feature large footprints. I intend to run these pendents very close to the water, which would not need the use of an optic.
Also integral to the board is a Microchip MCP9808 I2C temperature sensor. The sensors ground pad is brought out to one of the mounting screws, in an effort to get a good thermal path.
All connectors to the board are a series of Molex PicoLock blade-style high current flat wire-to-board connectors. I've successfully crimped the contacts, however annoying it may be, with the Engineer PA-09 which qualifies it for hobby use (as the Molex official crimping tool is $500). I've used the 10-pin and 6-pin connectors, as those are the only ones available in stock at any distributor (a downside to more unique connectors).
I have ordered prototypes (metal core prototype prices are nowhere as bad as they used to be) and stencils of the emitter board, and am continuing the design work on the driver and controller boards to sit in the stack.
Stay tuned to this thread!
)
