4 Wire 12V Native Pixels

[Croydon Lights]

Hi just saw a video by Greg Macaree on 4 wire 12v Native pixels that looks good and covers the problems of having a bad pixel with the back up data keeping the string working and has a lower wattage use than 5 Volt pixels which would reduce the need to Power Inject, he found his pixel at 12V to be 0.19 Watts per pixel
I think this is the way I will be going in the future, just need to wait and see if they will be PRE BUY on sale this year for them



View: https://www.youtube.com/watch?v=DbWpOXAheNo

 

[thewanderingpine]

Paul had some 4 wire pixels last year in the pre-buy, and I believe John at Ink Creations has some as well.
I got some of the seed pixel 4-wire variants in 2024 and had 0 complaints.

(Someone correct me if I'm wrong here - my understanding is that gs8208 is quite efficient at full white - but it's when it's only using 1 colour (or no colours) that the power tradeoff kicks in) I have been corrected below

 

[Skymaster]

(Someone correct me if I'm wrong here - my understanding is that gs8208 is quite efficient at full white - but it's when it's only using 1 colour (or no colours) that the power tradeoff kicks in)

On a single LED colour, the power scales fine between 0 and 100% (subject to gamma curve) .
The difference with GS8208 is it's not additive between the three colours, it's essentially the greatest of the 3.

Making an assumption of 16mA per colour - we can do some calculations to see how the behaviour is different between the two. (Note that GS8208 is up to 18mA, resistor 12V are generally capped due to the overly-large resistors)

So consider the following orange colour- Red = 100%, Green = 50%, Blue = 20%

WS2811 =
Red = 16mA x 100% = 16mA
Green = 16mA x 50% = 8mA
Blue = 16mA x 20% = 3.2mA
Total = 16+8+3.2 = 27.2mA total

GS8208 - the calculations are the same
Red = 16mA x 100% = 16mA
Green = 16mA x 50% = 8mA
Blue = 16mA x 20% = 3.2mA
But the total is MAX(16,8,3.2) = 16mA

And for full white:
WS2811 =
Red = 16mA x 100% = 16mA
Green = 16mA x 50% = 16mA
Blue = 16mA x 20% = 16mA
Total = 16+16+16 = 48mA total

GS8208 -
Red = 16mA x 100% = 16mA
Green = 16mA x 50% = 16mA
Blue = 16mA x 20% = 16mA
But the total is MAX(16,16,16) = 16mA

So you can see that between the bright orange and the full white, the power usage is the same for GS8208..... however is 76% higher for WS2811.
Essentially the most you'll ever draw from GS8208 is 16mA (again, using that assumption, which is not 100% accurate)

The trade-off, however, is that 12V resistor pixels will run down to around 6-7V before having colour issues due to voltage drop. GS8208 does require a much higher voltage - 9V - due to the series arrangement of the LEDs on the chip.


Also - the above calcs apply to GS8208 - some of the seeds being WS2808 or WS2815 etc have different behaviours again; and different power requirements.

 

[merryoncherry]

Said in the simplest way, the GS and other series designs always use the same or less power, so no tradeoff. (Because the same current goes through all three, it's the max of the three, rather than the sum. The sum can be the same as the max, or up to 3x as much). Give or take that some pixels run at lower current and produce less light. (The GS8208 is always lower power than 12V regulated for any given color, and usually less than the 12V resistor, but the GS8208 is brighter than resistor at 100%.)

But, I think the cumulative power consumption isn't what people are after. (Well someone probably is, but in that case I'd say look at standby power, as your pixels are usually dark, even in a reasonably active show... Also $.20-$.30 will get you the pixel, or many thousands of hours of full white, depending on your pixel and power rates.) People are generally after the total design power, so as to save time and money on PSUs, cables, etc. The total design power for the GS8208, WS2808, etc., is a lot less than 12V parallel designs, so what you spend extra on the pixel you'll probably save in wire, PSU capacity, etc.

I'd also mention that wire thickness is a bit limiting on some of the available GS8208s, the ones I have, the 4 wires are thinner than the 3 on most WS2811s. This hurts how many you can run without PI... they need to be less than 100 from power for full white. But, if you want, I think you can turn the little knob on the Mean Well to 13 or even 14 and be fine ;-). Based on the small test of a bit over 300 pixels for 100 hours in 2023 Halloween show to see what would happen. I have not tried this with the 12V seeds, gumdrops, or 2808s... yet...

 

[MichaelF5]

is the WS28 better power wise in a RGBW config?