| ??? 03/01/05 13:30 Read: times |
#88769 - This works Responding to: ???'s previous message |
I am working with a spec set by "professors in LED use" and I have to work with that spec since that is what is declared as "if you do so, the signs will last". This is : a 50mA LED is not to be fed more than 20mA at any time.
These signs fire up when buses parked in Death Valley, CA (120F and sunshine, just guess the temp in the bus) are started after the midday break for the evening rush hour. I have absolutely no knowledge how this spec was generated, I just know that it works. Of course, this makes multiplexing impossible if a sign is to be visible in sunshine. Erik |
| 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 |