Usb Well, I was going to say Christmas lights but are these really Christmas lights? They're all year round lights and this particular size 300 LEDs and a little USB controller and they came in this instance. I mean they're probably available from loads of places, but they came from the local supermarket. ShopRite the Isle of Man ShopRite in this very generic box. smart Global gizmos. Uh, notable down here it says Ben Ross which is Big importer in the UK of trashy, delightful stuff. but it's a very boring cardboard box. Not exciting at all, but that's okay. What's inside is what matters now. Although it says that these are rated 3 Watts which would be just over half an amp at the set of five volts. When you plug them into a USB power supply, they actually take about 350 milliamps so closer to about 2 watts and already you'll be able to see that slight Shimmer because this is a static mode now. I'll show you the mods and and to avoid epileptic things, I'll do it with the uh, the lights on so off. uh, all flashy at once which is oh no and ramping I think that's the old patterns thing? Oh, it is. Yeah, um, there's no flashing. horrible alternating backwards and forwards, slowly ramping up slightly pointless, feeding biops and forwards I'd guess uh yeah. the generic Christmasy light type one. um, what's this, uh, all ramping up and down? exciting. uh, and very, very unpleasant and then back hopefully to static. And because of the way these LEDs are driven, it's not really static, You can see that. Shimmer So I'm going to turn the light off so you can see these. It's probably going to well. I'll pause mum Charlie while I do this so I can get the correct exposure to show what they actually look like, that slight and take a breath I was going to say one moment, please and then I completely didn't but there you go. This is a rough indication of intensity. They're not too bad I mean it's okay for the amount of power is amazing. that's the sensitive LEDs you can see that slight Ripple particularly if I Well, let's take the ex. no I won't take the exposure off. that or just suddenly swamp out. but um, you can see that slight Ripple because for static, they are alternating battery supports very fast. And the color because uh, the camera is set for the bench lighting which is a daylight. it's making these look more golden than they are. They are sort of Fairly average Warm White Okay, watch your eyes. the light is coming back. the light is back. I'll unplug these and take this apart because that's what we want to see I can already see, look into it I mean let's take a closer look just through the shell I Can see the ubiquitous eight pin maker controller I Can see it, a coupling capacitor next, and a mystery diode. What's that for? is that polarity? Uh, I can see a little H Bridge driver. that's the bit that alternates priority and then one little current limiting resistor. On the other side, we've got a clicky button and a crystal. The crystal is there because these have that, well, um, it's let me know what you think in the comments. It's the timer function that turns these off automatically after a certain time, then turns one the next day. The downside of that is they're gonna have to be plugged into a standard USB power supply if you plug them into a power bank, which would run them for a long time if it's one of the sort of, uh, intelligent ones. A little bar graph that shows you how much energy is left when these turn off go into standby mode. The power bank is also going to turn off right. Tell you what? Where is my spudger? Where is my spudger? I Was using it recently for something and I have misplaced it one moment please and I've found it. So let's see how easy this is to open without bursting because uh, will it be glued shut? That would be annoying. No, it's not. It is not glued shot. This is good. it is. At the other end it's got Hot Melt Glue string relief on the wires. Uh, that was fairly easy to open I Think you will agree. Let's pop that. Well, let's not pop that out. Let's put some uh, isopropyl alcohol and which will instantly. Theoretically I'll just put tons in. Should theoretically just release that Hot Melt glue very quickly. Is it going to do it? Is it? Is it going to perform? Yeah, kind of. Yeah, it's done it right. I'm going to take a picture of the circuit board and we shall explore the circuitry one. Amendment please and resume. Here is the circuitry. So if I zoom down this, this is the USB connector in the side. It's interesting to note that a lot of the text is up this way, except the outputs are up the other way. That's just an oddity, but we have the USB connector here. I shall just write u S B uh I'll also write x T here because that is the crystal and the negative goes straight to the driver and the switch. here. this is a switch which links across and there is the little switch contact here I'll just draw this in an ugly way. So there's a button so it's actually using that as a link. One of the connections that goes through the switch to get the negative to the other side to actually power the microcontroller. I presume some microcontroller is marked 863f Probably a custom mass-produced chip from a company that specialized in Christmas Light and Software or something. Um, but it's based. It's got the same pin out that you'd expect of a microcontroller, so the negative goes across like that, but it also goes around and provides a negative to this device here, which is the H-bridge driver which swaps a polarity to that output more on that later. it's called a 2c08f that drew a blank. That's not a surprise. The positive goes through a polarity protection diet which also drops the voltage down slightly, which will have benefits for dissipation from that resistor. And there's a decoupling capacitor of roughly 100 Nano for our dimension in circuit, so that's not guaranteed across the two pins. The microcontroller and this is a classic pick-12 pin out. Um, the switch simply pulls pin four down to the zero volt rail and pins are two and three are for the crystal, which is probably 32.768 Kilohertz, 32. So that is correct. Uh, because that's a nice binary divide division of one Hertz which is what I'll be using as a Time base internally for its timer. That's all the crystals there for is the accurate timing of the Uh. It may possibly run the actual Uh pattern as well. But also the main reason for such a crystal like that is for accurate timing for the automatic switch on switch off mode. The outputs one, two, three, four, five, six, and seven go to the control pins of the H-bridge driver. Um, the positive connection here that went through the diode also goes to the H Bridge driver. The output from each Bridge driver, Which these are instant. These are purple, they look like blue, but they actually come across as yeah, they are purple. They're not to be confused with this or this. Um, one output goes via a 2.2 Ohm resistor and the other goes straight out. And if you want to double the intensity of these lights, change that to a 1 ohm resistor. If you want to use a shorter string and you want to get a longer USB power bank runtime, you could increase the volume of that resistor. It's entirely up to you. Let me show you that schematic. It's not that exciting. It's a very simple circuit. USB Command through the larger protection diode standard silicon Diode. There is the decoupling capacitor. There's the microcontroller that switched to the zero volt reel. There's its Crystal for reference. Uh, I'm making a guess here 32.768 kilohertz because it's a very common timing. Crystal The two out boots go to the the H Bridge as as does the power and then the output goes to the LEDs via that resistor. And here is the Uh Drift table of a very similar classic H-bridge If the tune pits are low, the outputs go high impedance because this is designed for controlling things like Motors and it will let us see a motor Freewheel um low and high. The output will be negative and positive high and low positive negative. and if they're both High it will uh, basically shunt the two outputs together for use in the case of Motors as DC braking just to stop things abruptly if that's used. but in this case it's not. This chip may not even have these features. It will possibly be just a a cheap, simpler one, but that is it. Things worthy of note: It would be nice if you could unplug it and store the last setting and non-volatile memory. That does not happen. Sadly, it just instantly forgets the pattern it had. So if I plug these in and I focus it to a more appropriate position. Um, oh, actually, you know what it did hold the less setting, but it doesn't always do it. After a while, it resets completely to zero. I'm wondering if that's just because the quiescent current of the chip is super low. uh, and that capacitor holds a charge just long enough to actually keep that? Um, But certainly when it was left on for a while, it did not hold the last setting. But earlier on when I did plug it and unplug it, it did seem to hold the last setting. Let's do that again. Let's unplug it and plug it. And let's put it to the first. Really annoying. Uh, well. let's do a really a blunt knowing Blinky right? It'll do that. Unplug it, leave it for a few seconds, plug it in. it is kind of remembering that, but it will forget reset to zero if it's left on plugged for a length time. But that is it. They're not super duper expensive. Uh, it's functional. It's bright enough for many applications. You can make it brighter if you want you don't want 300. LEDs You can cut it down to 100 and then you could use the strings for other things, but keep in mind they are. The LEDs themselves are wired and reverse parallel all the way along. so if you try to connect it just across, well let me down. No. I can't demonstrate because I've resold These Bars if I connected this across three volts. Um, one side would light and if I swap The Plight then I'll say red light. It just makes it more restrictive what you can do with them, but on that, you know it's a perfectly functional little device. It's fairly straightforward. The circuitry is pretty much textbook. The current draw is very loose. You could get a very good run time uh, from a USB power supply in these, which makes it quite interesting.