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DavidHenry
02-07-2009, 10:04 AM
If all 768 LED's were on, that works out to between 15 and 23 amps (at 20-30 mA per LED). So, just how much current should do I want out of the supply?

I realize that I'm not going to turn them all on, but want to know about what size supply I should plan to get.

Part 2, what if I have either 2 panels (which I will), or 4 (which I might), by how much additional capacity should I plan over a single panel (double or quadruple)?

David

51fordf2
02-07-2009, 12:34 PM
David - I never thought about it - but here's a commercial sign, with 840 leds, and the specifications:

http://www.pro-lite.com/images/indoor-plxpsb3014-large.jpg

• Model No.: PL-XPSB3020
- Character Height: 3”
- Number of Characters: 24
- LED Matrix: 7 x 120 dots
- LED Brightness: 3000mcd
- Display Area: 54"W x 3.2"H
- Dimensions: 57.6”W x 5.6”H x 2.2”D
- Volts: 7.5VDC
- Amperage: 4.3A
- Power Consumption (watts): 31W
- Gross Weight: 15 lbs
• Display Element: Ultra-Bright RED LED's.

R

Ronp
02-07-2009, 12:47 PM
Read this http://www.doityourselfchristmas.com/forums/showthread.php?t=397&page=3

djulien
02-07-2009, 04:21 PM
If all 768 LED's were on, that works out to between 15 and 23 amps (at 20-30 mA per LED).

I think LED-triks uses 16-way row scanning, so only 1/16 of the LEDs could be on at any one time.

don

DavidHenry
02-07-2009, 04:48 PM
Ok, looks like 4 Amps without a limiting resistor, or 1 Amp with. (per panel). Now I'm off to figure out which way the current control board design is setup, and what the BOM specifies.

David

Ronp
02-07-2009, 04:49 PM
They all can be on thats 1/16 duty cycle per led