| ??? 03/01/05 10:42 Read: times |
#88757 - cost... Responding to: ???'s previous message |
Russell Bull said:
I too found in 7segment displays that segments would fail - my conclusion was that the pcb (it looks like printed conductive ink rather than copper pcb) fails rather than the led itself. I cracked "open" one of the matrices (Kingbright) and it seems like a standard PCB (gold plated - obviously to facilitate bonding). But this might be different with other manufacturers. Russell Bull said:
...for the dot matrix, he had a product that was normal 5mm leds on a pcb (normal copper type) to get around this problem. This is viable and I have seen numerous displays constructed in that way, but it is more expensive than using the "dice". You need also some means to cover the PCB and perhaps to shield the LEDs from each other. You have also to consider the viewing angle of "discrete" LEDs. Russell Bull said:
Andy - as for the contradictory requirement - you've hit it right on the head! Although in the U.K this would be less of a problem. ... but the humidity is more of a problem... :-) Jan Waclawek |
| Topic | Author | Date |
| Further thoughts on large LED displays | 01/01/70 00:00 | |
| Practical findings | 01/01/70 00:00 | |
| I'd agree | 01/01/70 00:00 | |
| cost... | 01/01/70 00:00 | |
| Except | 01/01/70 00:00 | |
| Heatsinking | 01/01/70 00:00 | |
| Luxeon heatsinking | 01/01/70 00:00 | |
| Much brighter discrete LEDs | 01/01/70 00:00 | |
| 5 x 8 matrices | 01/01/70 00:00 | |
| size | 01/01/70 00:00 | |
| Contradictory requirement! | 01/01/70 00:00 | |
| This works | 01/01/70 00:00 | |
| "spider" LEDs are cool | 01/01/70 00:00 | |
| but that requires | 01/01/70 00:00 | |
| ...and also... | 01/01/70 00:00 | |
| track width | 01/01/70 00:00 | |
| 1 mm track | 01/01/70 00:00 | |
| Display of LED problems | 01/01/70 00:00 | |
| color code | 01/01/70 00:00 | |
Big sign | 01/01/70 00:00 |