 The Grammy goes to The new song Lady Aida for her new new new song. It was album of the year. Yes, okay Welcome desk of lady lady. What is on your desk this week? Okay, so This week, I haven't actually had a lot of time to do a lot of designing I've just been like keeping up with revisions and like, you know, you've seen a lot a bunch of stuff came in because there was a lot of shipping delays Through Asia and so like, you know, some of our components and suppliers Get parts from there and so stuff was delayed So you saw like we kind of had nothing for a couple weeks and then we had a big boost It's feast or famine as they say in the electronic biz now. It is so I thought Instead I could design something live using parts that can get yeah, because that would be fun So we had someone well first off. Do you have any user updates? No regular week No, Peter doing show and tell the show tell us on Ask an engineer and lots of surprises ahead some cool retro photos a bunch of coming soon It is a jam-packed week and as always we appreciate all of y'all at the time you spend with us You have lots of choices. We very much appreciate sporting us a 100% woman owned electronics company in New York City trying to do Good in the world. Okay, lady to back to you. Okay, so design something I'm working on it somebody emailed today and asked do we have something that converts a Raspberry Pi Pico to use Arduino shields and I was actually like well, we don't actually Have something that would do that, but it could be a handy little board and You know, you might be able to do a bunch of it with just like having it through holes So like it would be a mini kit Instead of assembly although like I'm now you know kind of thinking about it a little bit So you know only like a couple hours ago So I thought I would show what it would be like for me to design this and maybe So you can give me like 15 minutes and then we can move on to yeah great search ready. Yeah set go Okay, so you want to go to the computer? Well, I already have a our Raspberry Pi Pico package. I don't remember whether I made this or somebody else made this. It's been a while But I have a footprint ready to go So what I actually want to do is It's in my libraries So what I want to do is I'm actually going to Take an existing board and Got it. I kind of like to do that instead of starting from scratch because I you know, it keeps me from making Some mistakes, you know over and over again So I think I'll probably take the metro M zero which is sort of the closest Thing and I'm gonna copy and paste it and I'll make a new folder called metro Pico adapter And I got a lot of revisions, but I only want the last revision So let's look at this metro express and see what I can do so obviously this metro is designed for You know a rock chip so I think like I would I would like kind of take everything out of here And that would of course have to change the silk screen up but maybe I could keep a lot of this because like all the component locations are In spots that are like, you know the headers and the reset button And the micro USB port it would be cool if I could keep them kind of in the same sort of spot So I'm gonna start by Clearing out all that stuff and then in the schematic I'm gonna just delete the I'm going to Delete the samd 21 So it's gone and then I don't know maybe I'll keep the neopixel the SPI flash is already on the pico So I'll delete that. I might keep the SWD interface because there's a SWD Um RXTX LEDs, I don't know power supply. I don't need because the board has an on-board power supply Which is cool Fiber power supply. I might keep this on here for now Although it's a little funny because the micro USB port is on The pico so I don't know exactly what I'm gonna do there like I don't know if I can do a power port selection like this has to This has to go because I actually first off. There's no host enable. There's no USB host on the pico like there's no host select and The fuse I don't need because you know any fuse is already on the board and I don't need this shield So I've kind of I'm sort of deleting all the things that I Don't need and see what's what's going on now. Okay, so I kind of cleared out a lot of stuff All right, so next up I want to put that pico there. I think I'm going to Delete the ground plane So usually I have this for the streaming I have this Screen pretty low resolution. It's like 720p. Normally. I'm like 1080p so I would be able to see stuff a little clearer but Okay, so Let's now add to the schematic First up, I'll close this little inspector because I don't need it. Let's add the pico to already have the object for so Let's search for pico. See what comes up Great. Unfortunately, everybody has boards named pico now. It's kind of common thing Okay, so this is the Our pipe pico board and where is the Corner, it's not a very good spot for the pico So unfortunately doesn't look like it can make the micro us. Well, I can kind of make it in the same spot But I think it would be kind of sucky So I'm going to move it over a little bit Just so I have enough room for the silk screen so I'm going to delete the micro USB and and Delete the ground plane that we made for it and then I'm gonna delete this power ground plane and I'm going to move These LEDs out of the way and I can always find a spot for them later. All right, so now You know again, I like to have a you know, I want this to stick out like this micro USB here Um, maybe I'll move this down and I can move This down this down and You know, I have space for the silk screen, which is what I'm just kind of important Like I have I can squish this up a little bit, but I think like now I have a good amount of space so this is where the the the pico would sit and Then now I want to start assigning the pads so The good news is There's a lot of IO pins and One thing that I noticed on the At least on the Philhauer Pico core is that you can't remap pins. So pin zero is pin zero So normally I try to like map functionality, but I think it's more important to map pin Naming because the even you know, even if it's annoying to route I think people expect D zero on a Raspberry Pi to be D zero I think there's a way to quickly make all these lines, but I don't remember how to do it Okay, so like this This pin is DZ This pin is D zero and this is D one And this is D two and these are like the GPIO numbers so You know, like the thing is about the Pi three is like only the I squared C and the Sorry the analog pins are on specific pins. So these I have to kind of I'm kind of fixing on them. So This is a zero a one and a two And then I'm gonna keep you know the naming A2 I only think that's a little sad is the you know, the Raspberry Pi does not expose One of the analog pins because they have a connected to the the power monitor But that's okay, okay, so this is the ground So let's see how this looks It's let's go on to bear route so we can hide all the silk screen So the only it's a little annoying is like, you know, the pins are in the opposite order Then we would like would make for a nice route, but you know, we have a lot of space So it's it's annoying, but it's not like the end of the world. So for example You know, this is our D zero line and let me see so it's like This is my These holes these holes are gonna make it a little annoying You know, I think what I might have to do is This power supply might have to Get routed later because what I'll need to do is Route around So that this pin We'll need to go You know all the way around here to connect and then this is D1 Let's move this We do not need to yet. So then this is D1 and We'll route that, you know, right up against Here's that's not too bad. I just have to be careful I just have to make sure that I can get all of the wires I want Into this area because these mounting holes and These pads make it so I can't really route in and I guess I could try to route through but this actually makes it a little cleaner anyways because You know, I don't have to do any crossovers or vias So this is kind of elegant It's like that. All right, so that's that's kind of what I'll have to do And it's just it's just gonna be tedious. I'm just gonna have to like do all of them And then the good news is that I can still probably put the power supply over here It just has to be you know, I just have to make sure that I You know, I need a ground plane underneath this regulator to Make sure it can handle like the nine volt power supply and provide enough power So So I just have to make sure that like the ground plane I have isn't going to be cut up by that Underneath all those those wires that are underneath. So I Guess I could keep routing if people want or if they have any questions No, you're good. There is one question that I'll just ask Where can I get low-profile to punt that allows me to plug into from the backside of the PCB? That's tough, I mean we have we have slim headers that we use for some things like We have these two by twenty SMT Short headers and these are hollow so you can plug in from the bottom And they you know, they're surface mounts They pick and place on top quite easily and then you then you plug through. I don't know if that's the thing They were asking about okay What's up, you know, let's Let's go over to the great search. Okay. Well, I'll let's see 12 minutes on the dot So people people can see what I'm doing So I'm just gonna keep routing this and then when I'm done You know, I do all the pins and then I just have to pick a few pins for SPI now luckily for SPI These are named pins and so are the clock and data for I squared C and for those pins I Can I Can use any GPIO so because there's a lot of there's actually a lot of GPIO on the the pie But some of them are like, you know pretty high pins. So SPI will probably be like 18 19 20 21 I scored two all be 16 17 that'll leave GPIO 15 Unused and then you know, I can have a neopixel or something on GPIO 14 And so it'll be semi, you know, maybe it'll be surface mount and then you solder in your Raspberry Pi pico Question thoughts on the board having a quick connection Yeah, I'm gonna add one. I think I'd have space I could probably add one. Okay here Good suggestion. All right Ina 260 I on stock soon. I Don't know. I I don't know when stuff's gonna. Everybody wants to know 18 months when thing in stock when thing in stock when is Yeah, man want thing in stock. There is a lot of When will in stock be soon? Questions, okay, we don't know the answer. All right. Well, this is the start So, you know, maybe I work on this a little bit more this week All right, let's do the great search ready. Okay, the great search brought to you by the key need for it Thank you so much. Did you key? This is when lady user powers of engineering Every single week to help you find the things that you're looking for because it is a part drought and Lady Ada is an oasis of information that'll quince your search See what I did there That's your search Sounds like there's Okay, what is really going to marketing? I I might one day. Yeah, we can all dream. What is the great search this week? Okay? This week. We it's another customer request somebody asked us About it was equal to a quest that started a thought process So somebody asked us like oh, can you make a little adapter that would take? Like triple-a or double-a battery pack and convert it to USB-C and So you can like plug it in to something that wants USB-C because we have a lot of stuff that uses USB and On one hand, it's like, you know, it's kind of like the easiest problem and also the hardest problem because being a battery voltage alkaline battery voltage can range quite a bit and Especially if you have like four batteries, it can go above five volts or below and so, you know, the right thing to use is a buck boost converter and and So I was thinking about like, okay, you know, I we already stuck a buck boost and they could probably use that But it's not cheap. You know, they're they're like, you know, 15 to 20 dollars to have a good buck buck boost converter and also You know, they're more delicate. You know, just like you you can break it You know, they have some limitations and not you know, they're good chips and everything like don't get me wrong But I was thinking like I would be you know, what would be an easier way of accomplishing that And maybe do it in a little more inexpensive way and then I remembered that we did an ion NPI on e-fuses and e-fuses are An interesting chip that kind of takes care of your power supply issues It's you know, people are used to PTC fuses or just water fuses where you know, if the current goes over it'll pop Same with PTC fuses. It'll it'll open the circuit so you don't get too much current but what if You know, you want Something that's a little bit more You know, you're willing to spend a little bit more but you wanted to do a little bit more than just over current like under voltage over voltage You may be like light up something or warn you or latch when there's a failure And so if you just do that, so let's go to the computer and I'll show off. We did cover e-fuses So this is you know, I reference this ion NPI You know about a half a year ago and The you know, I I wanted to if you are more interested in more Details and what's funny is this is a part. I was like as I was like doing the search for e-fuses I was like this part will sound so familiar and it's like, oh, yeah, I didn't I am a P on it But I'll show you that a different e-fuse as well So this this series is quite good There's there's like seriously nothing wrong with it, but From what I could tell I think these fuses were only now they did have a 501 then this six three five one But there were a couple things that I noticed About these so let's look at the next six three five one to maybe Make another option. Okay, so one I Think I remember now what it was so this was a three amp fuse Which is which is totally fine But I also I wanted to see if I could find one that had a higher range and I think also Let's look at the data sheet Yeah, this had you know, it's not super high, but it does have an 85 mil ohm RDS on so it's not it's not low That said this was a you know This was a very good option so I did look for this, but I was also like well I want to see what what other parts are available Although this was this is a pretty good one so Right So let's go back here. So what I did is you know, I just basically because I was like I already know a part that's similar Let's look at active E-fuses and see what else is going on. So I did want this to Range from again about like four volts to six volts in and it would kind of give me a fuse at about five volts output And five volts up. It's a really common Voltage, but let's try selecting on the input to start and You know, I think you can go up to like 4.5 volts Input, you know something like that. That would be four doubly batteries because if it's four Alkalines, you'll get like seven ish volts and if it's Four nickel metal hydrides, you'll get about 4.8. So so that's good. So let's search for that and we've got a lot of options and Another thing I wanted to do is there's there's a lot of options. There's a lot of makers of e-fuses So I would recommend Looking for all them Most of them have pretty high currents The only issue I had is a lot of them and ones that I've used before like I've used some of the TPS They're out of stock and they're like heckin out of stock like you can see when this one might come back into Stock but the lot of them like they won't even tell you or it's like five years from now so I wanted to look for only ones that are in stock right now and the ones that are in stock right now, you know, I sorted by price and The NIST one is is in there. There's also this one from ST But I honestly got a little bit freaked out by the flip chip because it's a one millimeter by one millimeter Component and I'm like, I don't really want to live. I don't want to deal with a component That's that difficult to pick in place So I looked around and actually found that the TC KE Series and actually had a couple of nice Options which made it interesting. Well, first off, there's a five amp current. There's a wide input voltage range This is the data sheet So they have an over clamp voltage So it's like, you know, you could feed it seven volts and it'll clamp it down for you obviously, you know, you can't do too much or it'll overheat but You know, it will it will It will keep the voltage Active like you'll you'll be able to get voltage out even if it's a little high because like when you first Turn on alkaline, you know, when you first plug in alkaline's four of them, you're gonna get like seven ish volts so still just kind of cut it down to six volts for you and It was quite simple and has like a rise time capacitor set has a resistor for the limit and The only thing that wasn't as nice as the NIST one is that it's You needed to add a external External FET for reverse current blocking You know, these are pretty inexpensive. So it's you know, you can get a FET for like five cents So I thought it was still well within reason But I kind of like this and yeah, there's there's a Historicis on the UV low So, you know, basically for four point one volts, it'll turn back on and it'll turn off a little bit less than that Like three point eight. So this could be a good option for like, you know A buck boost is the right thing to do when you want to get You know, perfect five volts out to your device, but you know if you're powering You like a cutie pie board or something and you're like, look, you know, I want I Just need something about four to four to six volts in and I'm okay with it being a little bit Wiggly in exchange for the price because you know, the cost of these is E-fuses is going to be, you know, 60 70 cents, which is a lot, you know, there's no inductor Compared to a buck boost or two inductors There's no complexity. No big capacitors, you know, it's it's really just a it's a safe pass through So it's gonna be an interesting option You know, you have a battery port on one side and then USB connector on the other and then, you know, it basically just gives you like a rough voltage out And I think as long as people are aware of that, I think it could still be an interesting breakout board So this is the chip I've selected for the project the TCKE series the 805 that's a five volt output E-fuse And that's a great search All right, and then in the chat some folks were helping each other They found the parts they needed on different sites. So thank you everybody for being good to one another Thank you. That's our show for tonight. Okay 25 minutes on the dot. Thank you so much for joining us We'll see everybody during the week That was desk of Lediata my back to designing electronics for you quenched your thirst. Yes quenched your search