Lush Led vs Advanced Led Featuring Ace of Spades

Hosebomber;2192521 said:

I'll throw my two cents in here and attempt to clarify some of the information and misconceptions. Remember that this is in general terms and not all diode producers follow these rules exactly, and I will attempt to explain that a bit as well.

LEDs are rated by their max designed drive current. That current rating is as follows:
1 watt diodes: max drive current 350 mA (mil Amps)
2 watt diodes: max drive current 500 mA (mil Amps).... this is generally 2 single watt diode chips and are not made much any more
3 watt diodes: max drive current 750 mA (mil Amps)
5 watt diodes: max drive current 1000 mA (mil Amps)... or 1 Amp
10 watt diodes: max drive current 1500 mA (mil Amps)... or 1.5 Amps .... Note that once you get into this range there are a number of factors that change everything and the general rating of drive current to wattage may or may not be in effect.

The actual wattage of a diode will NEVER be the claimed wattage used (with a very small exception in some COB or chip on board designed diodes). The formula for wattage is as follows:

Forward Voltage x Amperage = Watts

This is displayed in data sheets as V for voltage, IF for Amperage, current forward, drive current.. and W for watts or power consumption.

Next is the Voltage. The voltage rises as current increases, but not all diodes use the same voltage. The following is taken from the datasheet for Cree XPE series of diodes.

Diode Color	Min Voltage	Max Voltage
Forward voltage (@ 350 mA) - white	3.05	3.9
Forward voltage (@ 350 mA) - royal blue, blue	3.1	3.9
Forward voltage (@ 350 mA) - green	3.3	3.9
Forward voltage (@ 350 mA) - amber, red-orange, red, photo red	2.1	2.5
Forward voltage (@ 500 mA) - amber	2.3
Forward voltage (@ 700 mA) - white	3.3
Forward voltage (@ 700 mA) - red-orange, red, photo red	2.3
Forward voltage (@ 1000 mA) - white, royal blue, blue	3.5
Forward voltage (@ 1000 mA) - green	3.8

As you can see, all of these 5 watt diodes have different Voltage forward depending on the current that they are driven at. Even though these are "5 watt" diodes the red, red-orange, and photo red all have a max current of 700 mA (Amber has a max current of 500 mA). This would technically make them a 3 watt diode (and 2 watt for Amber), but the manufacturer is not going to say "our 5 watt line that is sometimes a 3 or 2 watt depending on the diode you choose." Now lets see that the actual wattage of these diodes are. When Driven at 1 watt or 350mA the following is the actual power consumption of each:

Forward voltage (@ 350 mA) - white	1.07W
Forward voltage (@ 350 mA) - royal blue, blue	1.09
Forward voltage (@ 350 mA) - green	1.16
Forward voltage (@ 350 mA) - amber, red-orange, red, photo red	.74

The white diode (which is what they sell and market the most of) are pretty close to 1 watt. This is where/when the original naming of diodes by drive current occurred.

When Driven at their rated 5 watts (or max current) we get:

Forward voltage (@ 1000 mA) - white, royal blue, blue	3.5
Forward voltage (@ 1000 mA) - green	3.8
Forward voltage (@ 700 mA) - amber, red-orange, red, photo red	1.61

As you can see, the "5 watt" Red diodes, driven at 3 watt power, only pull 1.61 watts each. This is the diode that the majority of our panels are made from. This is also where a large portion of the misnaming and misrepresentation of LED panels come from. We have 100 three watt diodes in the panel so it's a 300 watt panel. But 80% of those diodes are red, this means our 300 watt panel only uses about 175 watts for powering the diodes.

The output of the diode will directly correlate to the drive current and the efficiency of the diode. In general terms (there are some new nano-tech COB diodes that do not follow this), the lower the drive current the more efficient the diode is, meaning that if you run the diode at a lower current it will have a higher radiant flux (light photons) output per watt (power input) than if you provide more current to it. However, you can drive the diode harder and get more radiant flux from the same diode at a lower efficiency. This gives us the ability to get more light in a small area at the cost of some efficiency. What this means is that you get a higher lumen per watt at a lower drive current, but more lumens per diode at a higher drive current.

Lenses and secondary lenses. In the above picture on the right hand side is the basic design of a diode. The chip is placed on top of a reflector cup, a membrane is added to protect the diode, a layer of phosphors are added to make it transmit the color wanted, then a resin dome is placed over the top to hold everything together and create the dispersion pattern of the light that comes out (in conjunction with the lower reflective lens). Nearly all high power diodes have a Lambertian pattern output. This designates how much of the light goes where. Again in general, high power diodes use a 120 degree Lambertian pattern (picture below). Secondary lenses change this pattern to a different angle. In doing so, more photons are directed in the area the lens determines, but at the cost of 7-15% of the radiant flux.

Now into some of the dirty parts. Epistar is one of the largest makers of chips. They are a Chinese company that started by attempting to copy the top producers and make more faster and cheaper. They did very well at the last two things, not so great at the first one. They produce mass quantities of chips at a super cheap price, however, they don't follow the general guidelines set forth above. They use the size of the die (the base the diode is placed on) to determine what they call their diode. Their 40x40mil diode is their 3 watt and 45x45mil diode is their 5 watt chip. These have max drive currents of 250mA and 500mA respectively. They do produce a wider range of colors than most companies, but in their quest to make super fast and cheap diodes, the resin they use for the diode lens (the dome over the chip itself) is very cheap as well. It degrades at a much faster rate than higher quality more costly chips and cannot withstand UV or IR light very well at all. This is also the reason you don't see the larger diode companies making low blue and UV diodes. You will be hard pressed to find a quality diode below 450nm and above 670nm. The resin and curing process for those resins to withstand the UV and IR light are much more expensive and time consuming to produce. Thus, they simply do not make diodes that require those methods. This saves them in material cost, production time, retooling between diode types, and a host of other money and time saving efforts.

If I left anything out or more clarification is needed please let me know.

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