
Two days ago the FedEx fairy delivered our first factory-assembled batch of Micro Pixels.
I unwrapped a handful, snapped a couple pictures, then plugged them in on the workbench.
Nothing happened.
Double checked the board layout against my schematic and the controller’s datasheet. The trusty ‘scope showed that all the signals were in their proper places. And the control program was the same one I’d used when testing the rough system prototype a few weeks back.
Bizarre. Potentially very expensive.
After another hour of testing, I discovered that the sample LEDs from the factory were different than the production LEDs. Each had six pins and looked identical to the eyeball. But a diode tester revealed that the polarity of all three LEDs was reversed 180 degrees.
+ + +
- - -
vs
- - -
+ + +
Turns out the LED factory had switched things around but not updated the datasheet on their website.
Oops.
Good that this was a test run of 100 pieces, instead of production assembly in multiples of 1500.
I used hot air to remove the three LEDs, then spun them around and re-attached.
At full power, these chips are exceptionally bright. They leave ghostly spots on my eyeballs.
Before running out of time that afternoon, I reworked three of the boards and chained them together. Everything operated flawlessly.
I love the simplicity of this new design.
P.S. We’ve had a suggestion for a new name for these guys:
Tripix
3 LEDs, 3 Colors, price approaches the $3 range in large quantities.
What do you think?
(Note: There’s some additional discussion on the controller design in the ‘comments’ section below. So click there to learn more.)