External Power Supply Info

[dvanteslaar]

I am trying to procure an external power source to drive the LEDTRIKS board, and am having a difficult time trying to put together all the pieces of information scattered throughout this forum and the LEDTRIKS manual.

I have finished building the LEDTRIKS PCB's, matrix, a wooden case to mount the matrix in (which is also covered with a piece of 3/16" plexiglass), the interface cable, and have just completed wiring up the anodes and cathodes to the PCB (which is mounted inside the wooden casing). I now need an external power supply so I can fire this bad boy up!!.

Ok, so far as I can tell, I need a "filtered" and "regulated" 5 Volt DC external power supply capable of providing at LEAST 3 amps at 5V DC....I DO NOT want to power it off my laptop power supply, so can anyone provide me with some more detailed information on where I could obtain something like this??

Thanks -

David

[Wayne J]

Check this thread out.

http://www.christmasinshirley.com/forum/viewtopic.php?t=270

[Jeff Millard]

Bench Top supply from ATX Power supply (http://www.christmasinshirley.com/forum/viewtopic.php?t=96)

[Jeff Millard]

Check this thread out.

http://www.christmasinshirley.com/forum/viewtopic.php?t=270

Not fair Wayne, you don't take the time to properly format your links so you get the post in first. That's not playing nice. I think you should take a time out and practice your URL links a little :lol:

j

PS, I absolutely love your sig!

[Wayne J]

Check this thread out.

http://www.christmasinshirley.com/forum/viewtopic.php?t=270

Not fair Wayne, you don't take the time to properly format your links so you get the post in first. That's not playing nice. I think you should take a time out and practice your URL links a little :lol:

j

PS, I absolutely love your sig!

ahhh, but the reason being, there was more than a link within the thread... there is valuable info too! :wink:

[Jeff Millard]

ahhh, but the reason being, there was more than a link within the thread... there is valuable info too! :wink:

What? That I love the sig???

:wink:

[dvanteslaar]

Check this thread out.

http://www.christmasinshirley.com/forum/viewtopic.php?t=270


Wayne,

Thanks for the information, but I must confess that stripping out an old psu from an old computer and then hacking it together to produce a bohemian psu seems a bit archaic to me, not to mention that the finished product is too large to be self contained within any reasonable sized casing!

THE LEDTRIKS board I have built will be mounted (and used) on a wall in a K->6 school and I cannot have a monstrous psu laying around outside of the LEDTRIKS cabinet!!

So, is there any other option available to me for powering this thing up? I would really hate to scrap the project after the time I've put in to it, but again, the finished product must be self-contained (including the psu) and away from the hands of little children.

Please advise -

David

[dvanteslaar]

Bench Top supply from ATX Power supply (http://www.christmasinshirley.com/forum/viewtopic.php?t=96)

Thanks for the information Jeff -

David

[teberle]

David,

Not all power atx power supplies are huge. what size are the approx. dimensions needed.

[Macrosill]

David,
I purchased a 5v psu from ebay for around 15.00 shipped.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170115611542

[dvanteslaar]

David,

Not all power atx power supplies are huge. what size are the approx. dimensions needed.

See photograph below

[dvanteslaar]

David,
I purchased a 5v psu from ebay for around 15.00 shipped.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170115611542

Hi Brian,

Wouldn't a psu like this work (see attached picture & data sheet)??

These make good bench supplies, because they:

1. have a monitor LED that's visible from the top
2. have an on/off switch
3. don't require any minimum load like PC power supplies do
4. have good regulation (±1% line, ±5% load)
5. have good efficiency

[ErnieHorning]

They also:
1. Don’t need a fan.
2. Semi water resistant
3. Are more astatically pleasing

[Macrosill]

David,
That would work fine. Just be sure that it meets the power requirements for the Ledtriks panel.

[wjohn]

I have not measure the Panle at 100% LED on, but I would be shocked it the current draw was more than 3 Amps. Anyone put a Multimeter on their panel yet? to test the load current in operation.

John.

[dvanteslaar]

David,
That would work fine. Just be sure that it meets the power requirements for the Ledtriks panel.

I couldn't find any information on the power requirements for the LEDTRIKS;

P = v * i
= 5v * 3A
= 15 W

Does anyone have (or measured) the load current when the panel is on? Does it draw anything near 3A at +5V?

David

[Macrosill]

I believe the "fully on" power consumption is about 4 amps. That is a worst case scenario if for some reason things locked up and all the leds came on and stayed on.

[coastermike]

I have not measure the Panle at 100% LED on, but I would be shocked it the current draw was more than 3 Amps. Anyone put a Multimeter on their panel yet? to test the load current in operation.

John.

I got about 840 milliamps with 100% of the LEDs on. When I was running some text across the board, the current varied between 50-200mA.

Michael

[Ronp]

I’m not one to question someone’s results but....

RJ posted in his how-to over at computer Christmas
On page 2 that the board Can use up to 4 amps

This may happen if the Pc locks up or freezes and the leds are
No longer being refreshed at 80 plus times a second so remember
There are things going on during the operation of the panel that
Most are not aware of such as the leds are being driven with much
More current than they are designed for but only for 1/16 duty cycle
( I believe they are 20ma leds and they are driven at 80 ma at 1/16 duty cycle)
Any questions about power consumption of the ledtriks should be forwarded to RJ directly
when in doubt ask the guy who developed it.

[RJ]

I would say you will be fine. When I first built the board I pushed it much harder than I let you guys to see when it would start killing Leds. Then I turned the current down for the best compromise I could get between not killing leds and brightness. Before we turned the current down the panel had a peak of 4 amps for a couple of microseconds just as the switching happend. You power supply would not mind this as the output caps will absorb it. After the peak it would fall to around 1.5 amps. After that we dropped the current so its well within you p/s capability. So have fun!

[wjohn]

I would say you will be fine. When I first built the board I pushed it much harder than I let you guys to see when it would start killing Leds. Then I turned the current down for the best compromise I could get between not killing leds and brightness. Before we turned the current down the panel had a peak of 4 amps for a couple of microseconds just as the switching happend. You power supply would not mind this as the output caps will absorb it. After the peak it would fall to around 1.5 amps. After that we dropped the current so its well within you p/s capability. So have fun!

Also, RJ's first design did not include the Current Limiting Resistor on the MBIs. I added this feature to the PCB to ensure that the Display LEDs were not being over driven.

I am pleased to see that the actual measured loads are <1 amp. <4 amp would be worst case without the current limiting resistors.

That being the case, a 15 watt PSU would be good for 1 to 2 panels.


John

[RJ]

Actual I did but they got missed on the first proto board you did. I missed them because the first testing I had done was full current to see if the leds would survive. I solder them to the bottom and still have that board. I asked you to add the resistor spots after that. you changed the resistance I suggested afterwards from my suggestion and so my personal controllers run a little less current than what the rest of you are, but if the leds don't die to fast its not a problem. In fact if you look at the how to on computer christmas and look at my board that pre dated the much nicer ones you laid out you can see the resistor is there.

[Macrosill]

So our Ledtriks panels use less than 1 amp at full on?

[RJ]

So our Ledtriks panels use less than 1 amp at full on?

Lot of light for less than an amp HUH!

[Macrosill]

Yup, so them the 6 amp 5v power supply should be enough to wrap my house in Ledtriks panels. Oh Yeah!!!