LEDWiz wiring to exceed 500ma

[whynotpizza]

LEDWiz question.

Ok, so I have 32 lights and cannot exceed 25 lights (20 milliamps each) to maintain no larger than 500ma.

So how do I get the additional 7 lights?

Suppose I splice a 5V wire from a separate USB plug, and connect this to an open port on a USB hub or the motherboard USB port, and daisy chain 7 buttons off this 5V line? Then, I could route the GND from each of the 7 into the LEDWiz to complete the circuit.

Would this be a problem? or will it still keep me within a 500ma or less on the LEDWiz amp draw?

  David

[atomikbohm]

If I'm remembering correctly the 500 ma total for all LEDs restriction is imposed only if you are using the usb connection to power your LEDs.  If you use an alternative power source you can go up to 500ma per channel. i.e. don't go over 500ma total limit unless you use the external power source option.  You could run a line from your pc power source to your LED wiz.  Just make sure it's the correct voltage and not over taxing the rail of your power supply.

You can see the install docs on GGG's web site (small chip http://groovygamegear.com/PDF/LEDWIZv2_INSTALL.pdf large chip http://groovygamegear.com/PDF/LEDWIZ_INSTALL.pdf).

[whynotpizza]

Thanks for the info on the external power options -- yes, it looks like this could be done and I also have those PDF's from GGG. However, it really is confusing to me this option and those instructions are not clear from GGG, and i'd rather not splice into my power lines off the computer -- instead would rather use the USB driven 5V option.

So I have the LEDWiz setup using it's onboard 5V -- and this 5V line drives the 25 lights and am wondering if I can "pull" additional 5V from another USB source for the remaining 7 lights.

  David

[um3k]

No matter what USB option you use, you'll never be able to to go above 500ma.  It's part of the USB spec that no port is allowed to draw more than 500ma.

[Haterot]

Is the 500ma restriction per LEDWiz? Can you add another LEDWiz, and then possibly plug those into a powered USB-Hub?

[VicBond007]

Is the 500ma restriction per LEDWiz? Can you add another LEDWiz, and then possibly plug those into a powered USB-Hub?

Powered USB hub is a viable option, just get a good one.  Check the amps on the power supply (1a = 1000ma).  That amperage is distributed between all of the ports, but if the hub is designed properly, it will never feed more that 500ma per port (so if you buy a 4 port hub with a 2a power supply, don't expect to plug one device in and get 2a from it.  You won't.)  This means that yes, you can buy a powered USB hub, hook up 2 LEDWizes, and get 500ma of power to each one, even though that hub is plugged into 1 port on your pc.  Because the hub is powered, it's only using the USB port on your PC for it's connection, not for power.  You can have up to 127 USB devices on one bus, so don't worry if you decide to split one port over and over.  As long as you've got enough powered hubs to run your devices, everything is golden.

Don't confuse this with sticking 2 LEDWizes into 2 different USB ports on your computer.  Multiple ports can share the same bus, and each bus shares it's power with every port on that bus.  You can however stick one in the front port and one in the back (or even one of those PCI expansion brackets that connect to the motherboard with the 9 pin connector) because each of those are USUALLY on different buses. 

It's a cleaner solution, but costly, especially if you have enough connections on one LEDWiz and your only reason for buying 2 is for power.

The other thing to consider is whether all the lights will be on all the time.  LEDs only consume power when lit.  If you're lighting your panel per-game rather than leaving everything on full-blast, there's a good chance that you'll never light every button (4 players games AFAIK top out at 4 buttons, so you might have 3-4 buttons on players 1 and 2 off, leaving you with only 24-26 lights on).  It's pushing the limits of 1 USB device, but you probably can't notice the difference in brightness between a 20ma LED and a 19.23ma LED.  You just won't be able to set up an attract-mode with all lights on at once.

[ivwshane]

Maybe my thread can help you:

http://forum.arcadecontrols.com/index.php?topic=87419.0

[drventure]

The comments about powered vs unpowered USB hubs is spot on.

And esp make sure the PS will output the max amps necessary. There's a lot of 7 port hubs out there with PS's that can't drive all 7 ports at 500ma (or even close).

I had a pile of props with my spinner,  trackballs and u360s till I got a hub with a PS that could really handle them all.

[Kayden]

I have 12 RGB LEDs hooked up and running off one USB port; that's 36 LEDs at 20ma = 720.  Are they dim and I just don't notice?  I haven't installed them yet, I just had them out and I was testing.

I was going to add some 5v goodness to the banks, but I wasn't quite sure what I was supposed to do.  As I understood it, I'm supposed to put the external 5v in bank 1 along with all the anodes that connect to something in 1-8, yes?  Is that screw terminal just acting as some kind of solder-less connection?

[VicBond007]

I have 12 RGB LEDs hooked up and running off one USB port; that's 36 LEDs at 20ma = 720.  Are they dim and I just don't notice?  I haven't installed them yet, I just had them out and I was testing.

I was going to add some 5v goodness to the banks, but I wasn't quite sure what I was supposed to do.  As I understood it, I'm supposed to put the external 5v in bank 1 along with all the anodes that connect to something in 1-8, yes?  Is that screw terminal just acting as some kind of solder-less connection?

It depends what color your RGB LED is running.  If you're making it fully red, then it's only going to light the red led, the green and blue leds will draw no power.  If you start cycling colors and mixing shades, then you'll have more lights on.  if all 3 colors in your RGB LED are burning at full strength, then yes, it's pulling 60ma.  Any other combination and it's pulling less.  An RGB LED is just 3 separate LEDs shoved into one bulb.

Do NOT put the external 5v power line into bank 1, or any bank for that matter.  Put it into the bank labeled x5v (the one that is probably currently jumped to the u5v pin).  Just un-jump it before you hook it up, otherwise you'll be feeding who-knows-how-many amps BACKWARDS through the board, and into your USB port, and i assure you that none of your stuff will survive.  All of your +5v leads coming off of the LEDs also go in x5v.  A screw terminal block will help with a lot of wires but with only 12, you should be able to stick them all right in there.  If you're going to use external power, you also need an external ground (the black wire on your PSU's 4-wire connector) and that goes in the screw terminal marked G.  The ground in the USB cable will not be able to take the heat.

This is based on the V1 documentation with the large chip.  if you have a V2 board, the documentation is more confusing to me, but I could work it out easily if you provided a top-down photo of the board.  It "looks" like GGG just divided up ports 1-8 and 9-16 when it comes to where the power is coming from, by splitting the old x5v port into what's essentially x5v1 and x5v2 (or 12v for that matter).  Can't say for sure until I actually see a v2 board.

[Kayden]

You were confusing me until I'll got to the end and read you were talking about version 1.  I thought by mentioning the banks you'd know I was talking about the version 2.  Bank 1 is post 1-8, etc. 

[VicBond007]

OK then yes, you want to feed a +5v wire from your power supply into bank 1, and another into bank 2 for lights 9-16.  You can use the same wire, just don't jump bank 1 to bank 2.  Split your +5v power line.  Never even seen a picture of a v2. All of the internet hype was about the v1 so that's the subject of all the pictures I could find online, hence why I had no clue as to what the screw terminals are labeled.

[Kayden]

Isn't splitting one wire and running it to both the same as running it to one and then jumping it to the next?

I'll try to remember to take a picture of it for you when I get home.

[whynotpizza]

Thanks guys for the help.

I decided to keep the 500ma (24 LED's) connected to the on-board USB of the LEDWiz and then use an extra USB port directly on the motherboard of the PC, and "spliced" a USB cable to pull an extra 5V line for the remaining 8 LED lights.

Works like a champ... 

  David