 This week on FPI, brought to you by DigiKey and Adafruit, it's CRELEDs! That's right! What is CRELEDs? What are they doing? What do they do? Well, they make gigantic bright LEDs. They're also known for CRE lighting, makes finished LED lighting structures and lamps. But today we're going to be talking about, and I'm going to get the part number correct, it's the X-Lamp XPG3 PhotoFill Select LEDs, that's the XPG3. So these are LEDs, I love the name PhotoFill, I mean that's a cool name. That's the way they call me when I take photos. Yes, PhotoFill. They call me PhotoFill. So PhotoFill LEDs are designed for horticulture, they're meant for grow lights and they're specifically tuned for the light frequencies that plants respond to best because if you are going to be using LEDs to... LED grow lights. Yes, LED grow lights, but if you're using LEDs to grow plants, I mean of course the sun is free, but in some cases maybe the case is... But the sun has all sorts of extra wavelengths, maybe you don't need those. Maybe you don't need them. And so in this case, you can get binned LEDs that are specifically designed for LED grow lights. Now, you might be thinking, wait, CRE, those are like the evil characters from the Marvel Cinematic Universe, they're technologically advanced and they have blue skin. No. This is CRE-LED and they're well known, I've definitely used CRE-LEDs multiple times. They're famous for really, really high quality LEDs that last a very long time, are binned and like very, very bright and customizable and they're very, very good for indoor white lighting especially, but they also do different LED colors. You're often not going to use CRE-LEDs for like little indicators, you're going to use them when you want illumination. Like you want a lot of light to flood something, not just notify you. So for example, you know, these are some of the LEDs they have. This is an X-Lamp series, which is like the package available in just a blue color with a typical frequency range of 451, which is blue. So maybe, I don't know, maybe the CRE, Future Science Fiction Race found these LEDs, they were so blue, turned them blue and then- This is what happened, sounds started. Yeah, they started fighting the marbles. Okay, but anyways, back to horticulture LEDs. So this series of LEDs are designed for, you know, whenever using LEDs to assist or to be the primary light source for plants, they've made LEDs before that people use, a lot of people just use kind of like these generic LEDs, not specified for, you use the frequency ranges that, you know, we'll mention it later, you know, what frequencies, but they weren't tuned specifically for like the different ratios of red, green and blue, whereas these LEDs are tuned specifically for that. And the reason that's useful and what people use CRE LEDs for is they're binned. That's like, they're specified and you're going to get the specification because when you're making an LED, you have the P and the N type of doped silicon material, you put them together. And in that boundary where the P type and the N type go, when the electrons and holes pass through, you know, they jump down from one level to another level and they emit that power as light. And you can tune and tweak that frequency that they emit. So like the first LEDs used doped silicon with aluminum gallium arsenide or maybe it was gallium phosphide, I don't remember. And so you have red LEDs and those were like the first ones. And then as people tried different materials like gallium three phosphide or sorry, aluminum gallium, indium phosphide, you could get greens or zinc, uh, silanide or in again, in indium gallium nitride, you could get violas and ultraviolet. So you get different frequencies. But in general, when you are buying a red LED and you're paying, you know, a penny or two for a red LED, you're going to get something, you see here the lambda, the wavelength is between, you know, about 600 to 700 nanometers. It's not going to be precise and you're not going to get in matching between the LEDs. You're going to get something approximate. And that's why it's so cheap, right? You don't, you know, you're not paying for high precision. You just want something where the red LED on your microcontroller board or your indicator just lights up and it's close enough. Um, and so a lot of low cost LEDs, even the ones that are illuminating, they're not going to be matched. Like you're going to get whatever brightness and whatever came off of that disc when they diced up that silicon, the PN junction, you're going to get whatever came off of that plate and each plate might be a little bit different. And that's kind of your problem. Um, when you have plants and, you know, you've got these, um, green leaves and they're absorbing the light and, uh, they're using that light to convert the carbon dioxide, um, into, uh, oxygen. Also takes, uh, you know, nutrients from the soil water and they, you know, using all the hydrocarbons and the light to convert them, um, turns it into energy that the plant can use. And then when maybe we eat in those cases, um, the frequency of light that's coming from the sun. Now, the sun happens to be a pretty broad spectrum, but not every frequency is used. There's certain frequencies that are absorbed, um, much better. So you can see, you know, it's kind of worrying about this on Wikipedia. Can I sort of assume that you want the widest, uh, band light, but actually you don't, you sort of want this, you want like a non-linear wave where it's kind of centered around the visible spectrum. Um, but it's not perfectly linear. And so like you kind of want a lot of red and you want blue and then green is useful, but it's not like the most. And so, you know, a lot of people use just red and blue light and so you can see the LED light panel on the top right there from a NASA experiment. So you can see space is becoming important here. This is one of the, the Cree aliens race learned about this, they found our potato plants. That's right. Um, and they, they love these Cree LEDs. Um, but the, the amount of radiation and the frequency of the radiation is important. And it does affect, um, how the plant grows in different plants have different radiation. And like, you know, if you have the sun again, it's free. Who cares? But if you're going to be paying for the electricity for these lights and you have to pay for the LEDs, you want to get the most bang for your buck. You want to get the most efficient transmission of electrical energy into, uh, photonic energy that will be absorbed and then turn into plant energy, whether that's corn or flowers or basal, what have you. Um, and there's a lot of papers actually. There's, there's a whole, um, journal called court of science and there was like dozens of articles in it about, uh, different LEDs and they, they tested all the different, um, frequencies and ratios between the LEDs, uh, and brightness is and what types to try to tune it because there's actually a lot, there's a lot of investment in it because a lot of people are moving from, uh, halide lamps or fluorescent lights to LEDs because you don't have to change the bulbs. They don't burn out. They don't really dim over time. Um, they're a little bit more expensive, but like once you buy them, you're set and they run for, you know, a decade or plus, um, LED lights. They're not, you know, they don't last forever, forever, but they last a lot longer than an incandescent bulb. Um, so the photo films like LEDs have red, uh, and blue, and then you can tweak the amount of green and you'd also, I guess, add a separate photo, red LED, um, if necessary. And so you don't actually want white, like a pure white color. Um, you actually want this kind of ratio mix of green and blue. And, um, you know, to be honest, I, I delved into this for a few hours, but you can go on for years and study this. And I'm assuming that, um, Korea and their wisdom, uh, figured out the exact ratios that most people are interested in. And so these are the distributions they have of the, um, different lights. There's three versions, two, two point five and three, um, and they basically looks like there's a peak about, like, you know, 450 nanometers, um, and that's where you're going to get more or less, um, relative radiant light compared to, um, the, the more blue ratio. Um, so this is, uh, the order codes. So you're going to get, um, the, the green blue ratio, how much green versus blue, um, some plants, I guess, do better with more green. You know, again, you're, when you buy two, three cent LEDs, it's called green. They're going to give you the material. You're going to get it somewhere within, you know, the, the, um, the brightness that you think it is. When you buy Creelities, what you're paying for is that guarantee that, um, you're going to get the exact frequency and the exact power output that's going to match. It's a little bit more expensive, but then you don't have to go back and rework it when the LED dies, because the Creelities are just designed to last a lot longer, uh, and deal with, um, the thermal load of lighting a huge grow light. Um, and, uh, second, they're going to get the binning that you're expecting in this, this ratio is going to be precise. And the way they do it, of course, is they make all the LEDs and they test them and then they sort the LEDs out. So, um, you know, rather than trying to control the doping, which they do also, they'll bin them after manufacture. And so you'll get everything on the wheel is going to be the same match. Um, these LEDs are, are very bright. You'll notice under the DC forward current, um, it's two amps, right? That's the maximum, uh, current range. So these are very small and they're extremely bright. Um, definitely do not look into them with the remaining eye you have. Um, then forward voltage of, you know, it says if you run at about a watt, it's about three volts. So you'll definitely need a, uh, LED driving current, uh, management system. You can't just like put a resistor on them. It's, it's two amps. It's going to want, you know, butt converters and you probably want to have them all in series. So maybe you boost it and have a very high voltage that you can control the current going through a string of LEDs. Um, because you're going to be pushing two amps through them, there's also a very specific footprint for the copper, um, and how you want the paste, uh, to be deposited. You know, there's also a lot written about how to design, uh, products using these LEDs. They're very small for the amount of power going through them. Illuminum backed LEDs are strongly recommended. Uh, you might need heat sinking. Um, and you know, depending on having your heat sink, you might even need active cooling. So you might need a fan, not a very powerful fan, not as powerful as you would need for HID lights, um, but definitely something to kind of move the air through because even though LEDs last a very, very long time, they, uh, you know, the bonding wires in the substrate won't last if it's, uh, overheated too much. Available on DigiGay. That's right. They're in stock, all the different bins, but this is the one we picked out. Um, and I'll just show it on the over here to show you how small it is. Um, it's a very small LED. So think about putting two amps through that. It's going to get really hot. Uh, so you're going to definitely have to think about how you're going to heat sink this. Don't, don't just plop it on a PCB and think you're going to be happy. You're going to be, it's, you know, it'll, it'll actually get so hot. It might desolder itself. And there's a video and wrap up by an API. Hi, my name is Derek Miller. I'm the R and D applications group manager here at Cree LED. Here you're looking at our new J series three volt G class LED optimized for horticultural lighting that we call photo fill select. In this LED, we were able to optimize the phosphor mixture so that you can pair it with our XB GDS photo red to get the highest efficiency horticultural LED solution available now. This fixture behind me has 1152 photo fill select mid power LEDs mixed with 48 XB GDS high power photo red LEDs. In this fixture, we were able to demonstrate up to 3.25 ppf per watt efficiency. This fixture has a two channel tunable solution so you can get exactly the amount of red that your plants need. Our photo fill select LEDs are available in two different recipes with both a high green to blue ratio and a low green to blue ratio. By selecting the two different recipes of green to blue ratios, you can mix and match to get exactly the spectrum that you want.