 and welcome to Discalade Data. Hey everybody and welcome to my desk. I hope you guys are all staying warm. I know that there's a lot of cold snaps around the US. I don't know, maybe it's also cold in other countries. But on my desk, it's nice and toasty. We got the soldering iron on, the hot air gun. We're making all sorts of prototypes. Let's go to the overhead and check out some of the prototypes that I've been playing with. Okay, so first up, for our QDPI boards, I love making BFFs, these little boards that either plug onto the back or in this case, it's gonna plug on top. So for example, one BFF that I got prototype for is the CAN BFF. I think I tucked, I think I showed off the design last week but now I've got it. And this goes like back to back like so. Actually, I think it actually goes like this. I have to test this out. And it uses, you know, it's a nice little compact package which I think is cute. You just power it with USB and the five volt USB is used for the CAN bus voltage. And then you've got ground, high and low signal. This uses the MCP25625, which is basically an MCP2515. It's like the most popular CAN bus controller chip with a transceiver built in. And I know that some people are like, but wait, the ESP series can do CAN bus natively and RP2040, you can bit bang it. Yeah, but like it's kind of like, it's challenging and the API is different. And I feel like, you know, it's only a couple of bucks maybe just getting a CAN chip over SPI. And like, you know, it's, it's good to go. It'd be easier because you need a transceiver anyways. And then there's some jumpers on the bottom if you want. The interrupt, standby or reset, pan used. Okay, so that's one. And then I designed another one. Mr. Lady had sent me this link. Somebody made a board that allowed DC power in for a QT Pire shower board. And I was like, oh, that's a really good idea. And Erin was working on a project. She's, you know, just projects for us that she needed to power an ESP32 QT Pire from 12 volts. And I was like, I don't really have, so you can wire up like a buck converter to do that. And she's like, well, I want something simple. So I designed this board and inside here is the MPM 3610. So maybe pop back to my computer real fast and I'll show off this chip. So we have some breakouts for this chip. The MPM 3610, the MPM 3610, it is cool. I saw this actually in Arduino boards to start. Like I think the Arduino, ooh, the Giga, I don't remember. One of their boards used the MPM 3610 and I was, or like a bunch of their like Nano boards used it. And it's a really cute little chip. First off, it's not too expensive. It's only a couple of bucks. It's in stock at Digi-Key. So if you let's look it up real fast, MPM 3610. It's an adjustable buck converter up to like 20 volts input, one amp output and fine, you know, it can be adjustable but like it's great for like three to five volts I think is what it can do. And yeah, it's like, you know, basically a dollar, $50, $25, whatever. And what's nice is that it's got the inductor built in. So you'll notice like, whoa, there's no like inductor or diode or transistor or whatever, everything's internal. All you need is like four passives just to like set the voltage. So if you look at the overhead again, so I needed to go with this partially because, oh, can you go to the overhead? I didn't really have much space because I wanted to have this DC jack and like I couldn't, you know, I moved it to the very top of the board but then, you know, it's like I went out of space. And then I wanted a terminal block also so you could choose whether you want a DC power input. So you've got like, you know, DC plug or, you know, a battery input. And then there's a diode protector because, you know, you can wire this up backwards and maybe you have like a center negative for some reason. And then there's a buck converter and then you can barely see two little 0402 resistors to set the voltage and then a bunch of capacitors for capacitance. And then it gives you five volt out. So the only thing that's different is usually with these, I have them like back to back but I didn't make this back to back. And the reason is because this has this, you know, these pins that come through and I was worried that people would just solder it onto the back and it would short because it will, it'll touch the components on the bottom. You can see it's touching and not good. You could like really damage your board. So this one I decided, you know, because the DC jack is so high, it's gonna be, you can see here, it's a lot of focus again. This is a, you know, top side style. So let's see USB up. Yeah, USB this way. So it goes like this and then, I don't know if this is plugged in, but I think it is. And then you power it and then bing. And then it's running circuit pythons. You see the LED blinking. And now you've got get running off of anything up to 20 volts. I wish I did 24, but, you know, I think enough people are willing to like deal with this 20 volt max. It's still a lot. A couple of, you can run off double A batteries or like triple A's or a couple lithium ions and parallel for a DC jack. And then if you want to run it off of USB-C, you can use one of these USB-C, this is what I'm running, USB-C to DC cables. And then it's like, okay, you can have a USB-C. And, you know, if you plug into the DC, of course the same voltage comes out here. So if you need 12 volts to drive something else, it's like you can kind of share it. So this design's done. And just one little change I made if you go to the computer again, thank you, is I was like, oh, you know, chances are if you're using DC, you want to like attach it. So I added these little like mounting wings that come out the side. And you see little holes here. You can break this off. But there's four mounting holes. And then you can put the cutie pie on top. And you've got like a little compact thing that you can even like attach onto like a design. And then of course, if you want more BFFs, you can always stack them. But this one would be on the bottom. So that design, I think it's pretty good. So the only change I made is to add these wings. I'm going to book them and this is good to go. Okay, a couple of minutes. So let's keep rolling. Next up, thinking of 12 volt power. Another thing I designed is one issue I've got is we've got, it just comes up a lot for me, more than you think. So you've got these like analog RGB LED strips. And that one is like this one, for example. So these LED strips have red, green, blue, or sometimes they're like only white. Like sometimes we have like a 12 volt neon, like these strips. And these are nine to 12 volt DC. And the problem is you want to PWM them because you want to dim them or brighten them. We're like, you know, you have multiple colors and you want to fade them in and out. But then you need a transistor and you need like resistors and you need like the DC input that gets like kind of complicated if you want to, if you want to control, especially the RGB ones, like you can see here, like you have a metro and then you have these two transistors. It's like, it's a bit of wiring. So I wanted to make this easier. So this design here is, it's a stem of board. So you have like a JSTSH connector coming in. So it's like a little bit like this, you know, the BFF. So you have the cable coming in. And then it goes into a, this chip, which is, let's go to the schematic. It goes into a WS2811, which sounds a lot like 2812, which is like neopixels. And in fact, these chips were the original, if we go to the Flora V1, which is discontinued, the original neopixels from way, way, way back when, they had a chip on the back. This was before there's all in one neopixels. Like now there's like a little LED with four pins and like data-in, data-powered, you're like, good to go. But before that in the old, old days, back when, before we had cell phones and Netflix, we had to put chips on the back. And then you'd have an RGB LED and it's common anode and you'd wire it up and then you would still use the same protocol, but you had to double-sided. And then this is discontinued because now the version of course has the chip inside the LED. But the reason we want to have the version with the LED external is because then we put it through an inverter and into three n-channel FETs and these are like three amp n-channel FETs and you have a V in here and then these can sync the 12 volt signal, lots of current. So you have big LED strips, lots of LEDs, 12 volts, you have even 24 volts, I think they can handle. And the V in is also regulated down to five volts here to power the WS 2011. So basically what I'm making is something that looks like a single neopixel but actually drives like an analog LED strip or even just like one of those big three watt LED chips. So if, I think we have like three watt neopixel LEDs. So if you look at like, yeah, like these is the same kind of idea, right? Except that they don't, I don't know what these extra transistors are, but they have a WS 2011 here and then big LED and then transistors should actually do the driving. I think they do the same thing where they invert twice. So what's cool about this is that like, you know, if this works, like all you do is give it like the signal can be three or five volt DC. You give it 12 volts or nine volts V in and then like boom, here's a terminal block and you can just like drive your analog LED strips and this should ease my annoyance of every time I have to do a demo for these strips. I'm like constantly rewiring the same circuit. So that's coming soon. And we'll talk about on INPI why I chose this and the design of this, not INPI at the great search. Lastly, right before we switch over to the great search we have one, it's not out yet. Don't ask, it's a secret. So like two years ago, we were doing a lot of floppy stuff and I had to take a break from it because I couldn't get, there were so many parts I needed I couldn't get that I was just kind of like going a little nuts. I was like, okay, I'm gonna use this like buck converter. Oh my God, I can't get it. And then it's like, oh, it's e-fused. Nope, that's not available. Like when we get this other version and like it got like so annoying and the prices were nuts. So I designed, this is actually floppy disk sized and this is just like a rough draft. This is gonna change around a lot but it's an RP2040 with a micro SD card and SDIO format and a TFT. And then this is a 12 volt buck converter. So you can give it 12 volts and it'll give you five volts as well. So getting a split supply for five and 12 is annoying. And then down here, either your standard 34 pin IDC floppy, I don't know if I have a floppy drive here, or a laptop floppy and the laptop floppies use FPC connectors and then you know your lovable Molex that everyone knows, the chunky power supply. And then all the level shifting, weight protecting and then current monitoring too, this is the current monitor to monitor the five and 12 volts to see how much current is being drawn. Also verify that the voltages are good because I noticed that if the voltages dip too much you actually get some pretty, like you get bad data out. It's actually quite sensitive. And then this is an e-fuse up here. So this chip, we'll look at it real fast. This schematic is a little bit of a mess. I gotta clean it up. This is the power supply. This is the monitor, the e-fuse. The TPS 259 540, which we'll talk about some other days. This is pretty cool. You give it the power input and it will only enable between like the valid voltages. So I can tell it like, hey, below 12 volts or below nine volts, I don't want you to turn on and let the power through. And if it gets above, turns out like 13 volts or so, clamp the power output. And then if it overheats, the red fault that Lady turns on. So this will make sure people don't accidentally plug in like too high of a voltage or too low of a voltage. And they're like, oh, why isn't it working? And then this is that buck converter. And yeah, I don't know. It's coming together. This is just the first draft. You see, I got a lot of space. So I put this cute bunny. Please design this adorable floppy bunny. Floppy ear and bunny on some floppy disks. Very cute. So it's not out yet. Don't ask. I'm not talking about it. Maybe a couple, maybe after a couple of drafts, I'll get this going and we'll do some more floppy projects. Okay, cool. We're ready to do the great search. Where are you? The great search brought to you by DigiKey and every single week, Lady, the power of engineering, I hope you guys can find the things you want on digikey.com, Lady, to what is the great search this week? Okay. Great search this week if we're gonna look for a triple inverter and it has to be really, really small. So let's go to the computer and I'll show off the design that I'm working on. So here is a board I'm designing that'll take a NeoPixel signal, WS2811, 2812 and convert it to analog LED strips. And the WS2811, if you look at the datasheet, it can handle high voltages, but it doesn't do high current. It only do like 20 milliamps per string, but I wanna do much more than 20 milliamps because there's many in parallel. And so I need a transistor output. I need like strong driving transistors. The problem is if you look at this, this is a common anode output, which means the LED is on when the signal is low. But if I have n-channel FETs like I do here, a low signal would be off, not on. So I actually have to like invert the signal before I feed it into these power transistors. So first off, because it's common anode, I think it's open drain. Actually, I don't know, but I guess it needs open drain. I have a couple of little pull-ups here, just 4.7K. And then I need an inverter. And this inverter, I want it to, it can't be open drain. It has to be push-pull. So you should get trigger output. Easy three channels, red, green, blue. It should be able to run off of five volts because that's the signal level. And it should be small because it needs to fit on this board and it has to be like really tiny, but I don't like BGA. So like small, but maybe not too small, like just right, medium. So let's go to DigiKey and see what we can find. So first of all to look for is we just type in inverter. I mean, here's like, I can actually use transistors to do the inversion, but again, I want it to be very small and I want it to be push-pull. So let's look. So gates and inverters, 13,000 options. Well, we'll pare it down. Don't forget, there's dark mode, but I'm not gonna have it on. Okay, so let's only look for active. Let's just start with active and normally stocking. Okay, and then I want it to be an inverter gate. Also known as a not gate. I don't want any other gates because I don't want multiple inputs. I want one in and one out and it just is the opposite. Okay, so let's select that. Okay, now we're down to 1500. Number of circuits, three. If that's options, sometimes you can't get the number you want, so you're like you want four. Four doesn't exist. It's like one, two, three. Like the ones are very cute that will slot 23s or whatever. You get three and then goes up to six with nine. Okay, cool, no problem. Apply. Okay, now we're really down to only 140 options, which is nice, we're comparing this down. Next, we talked about open drain versus Schmidt trigger. So the reason I want it not to be open drain is because I want this to be able to pull the gate of these transistors high. It has to pull them high and I want to do it nice and strong, nice and fast. Why have pull-up resistors if I don't need them? Sometimes you want open drain, not this time, we're gonna go with Schmidt trigger output. And then voltage supply, I remember I said this has to be powered from five volts because the input is coming from the WS 2011 and my only power supply is five volts. So we're gonna not select these 3.6s and yeah, this one's fine too, 4.5, but the voltage might be a little lower. Okay, good. And now we want it to be small, but not too small. So let's see what's available because now I've actually kind of pared it down to about like 100 options. Okay, so I don't want BGA, definitely. So let's just select everything with that because I'm not doing BGAs. Okay, I only got rid of two. Okay, so good, there's actually quite a lot of options. Another thing is, okay, I'll be honest, there's like 74 logic and there is TC7 logic, I don't really know the TC7 logic. I do know one thing about, so T logic is transistor level output, so it can shift down, but actually we don't really need that. I'll think I'll just go with whatever is available that is kind of like the low cost and around. So let's look at by price. Let's see what's around. To be honest, like almost all these are good. Oh, there's some marketplace options, which are okay, but let's go with just to make it easy so I can only buy whatever, because marketplace is just a duplicate of whatever we already have in stock at DigiKey. Let's exclude that. Okay, so there's these exons and there are some MSOPs. These are good. I'm a little biased against the TC7 series just because I'm not familiar with it. So I'm gonna select only the 74 series because I know 74, although I'll be honest, I'm sure that TC7s are equivalent. Okay, now we're talking. Okay, we got a lot of exons, Vsops, 74HCs. Let's look at what's most in stock, because that's another good way of telling, like what's the most popular? This one looks not too bad. Basically anything that is 74LVC inverter. This, I don't know why. You know what? I'm gonna select logic type, sorry, features. I'm gonna not sub the X. I'm gonna have just Schmidt trigger because I don't know why I had, I think, open drain ones. Okay, here we're talking. HC series, LVC series. The difference between the two is basically like voltage, quiescent current and logic level high and then is there voltage supply? Both are basically the same. Current, output high, you know, I actually want the higher current one. I'm gonna go with the LVC because I wanna be able to like really turn these on very quickly. I don't think it's gonna make a big difference, but if they're all about the same, something that can slew a lot of current for me, good to turn on these transistors. So I'm gonna go with this one, the SN74LVC33814 inverter and there's lots in stock and they're like 30 cents apiece. So this is my pick. Hey, that's a great church. That's a great church. Where are you? All right, that's our show for the week. Thank you so much for joining us on DiscoVidiata. We'll see everybody throughout the week. Keep an eye on our blogs, socials and more every place that you can see us. Lots of surprises, lots of new products. We will see everybody next week. Bye everybody. Have a great week.