LED Wiring Help Needed (LEDs, LEDWiz, Wiring, and Power Source)

[Wienerdog]

I have one LED Wiz and lots of LEDs but I need some help wiring up and getting a power source.  My attached picture says it all.  I have 78 Super Bright (or Ultra Bright) LEDs (71 blue and 7 red or maybe white). 

It's looking like I might group the marquee lights in groups of 4 for the LED Wiz (LEDWiz Output 1 = 1,16,17,32; LEDWiz Output 2=2,15,18,31; etc) Total LED Wiz 8 Outputs.

The Control Panel Lights would be in groups of 2 (LEDWiz Output 9=33,34; LEDWiz Output 10=35,36; etc).  Total LED Wiz 16 Outputs.

The Seven Button Blue LEDs would be individually controlled by the LED Wiz.  Outputs 25-31.  Total LEDWiz 7 Outputs.

All Seven Button Red LEDs would be all controlled by the final LED Wiz Output #32.

All of the LEDs will have a resistor and be wired to a central location with the LED Wiz, I assume that a common (-) can be used across any of the LEDs.  I'm wondering what I need to power these LEDs with, and how to wire it up.  Have I missed anything? 

[MikeQ]

The LEDWiz is your power supply.  You may want to consider external power as well (hooked to the power input on the LEDWiz).  A standard USB port supplies 500 mA which may not be enough to power all the LEDs when all on at the same time.

[Wienerdog]

I haven't run the numbers lately, sorry for not having the exact specs on the super bright LEDs.  I definitely need the external power supply because I'm running almost 80 LEDs.

I'm wondering if the computer power supply can handle that current or is it definitely an external power supply that I need.  If so, does anyone have a suggestion on which one to buy.

[MikeQ]

If you are talking about running a molex connector (+5 pin) from the power supply to the LEDWiz, yes.  This would suffice.  You can also get externally powered USB hubs.  You would plug the LEDWiz into a hub and the hub into the computer.  The hub will also have a power supply that will plug into a wall.  If your not going to be using a USB hub for controllers or anything else then the molex would be the cheap way to go.

You might ask RandyT about the 500ma issue.  I thought he said that each output on the LEDwiz could handle 500ma.  That seems odd to me though.  You may still have an issue if your putting a lot of LEDs on a single output.

[RandyT]

The USB spec says you can pull up to 500 ma on the USB port.  This has to include the power consumed by the device as well.

The smart bet is to give that one some space. If think you will be approaching that figure, use external power (from the PC power supply.)

Once you have external power connected, each output can handle up to 500 ma.  In theory, that's 25 x 20ma LEDs, but again, if you find yourself getting close to this figure, use more inputs to be safe.

RandyT

[Wienerdog]

If anyone is approaching 25 LEDs per input, I hope the cab will come with sunglasses. 

I'll have to check how high my computer power supply is rated, but I'll plan to use the 5v output from there.  I didn't realize that it would be able to handle 80 LEDs, but it looks like it will be fine.

Thanks for the input, let me know if you have any other advice.

[RandyT]

Point of reference:  A normal hard drive uses about 800ma on the 5v line.  That's a lot of LEDs.

You shouldn't have any problems using the PC power supply.

RandyT