 To research what you buy if you're doing digikey every single week lady user powered of engineering to find The most precious things in the world right now electronic parts Okay, so we're gonna go to digikey.com and try to find something this week. What are we gonna try to find? Okay, so here's what we're gonna find so you know this part shortage is kind of an ending Yeah, let's go to the computer and I'm gonna tell you a story Here's a story. It's a story about a part of care find So the I've actually you know a while about a year a year ago I ordered, you know a year's worth of components from ST sensors, you know, I've been ordering a year's worth at a time usually instead of a quarter quarter's worth because it's been so tough to get parts and Some parts from ST I've been able to get like I got LSM 60 socks is and I got some you know ISM 330s But what happened is I often what I've liked to do is I like to make a combo IMU where I take You know a accelerometer gyro I stick it with a magnetometer because it's actually not that usual to get a nine-doff in one usually don't get all Accelerometer gyro magnetometer in one package. There's the LSM 90s one But like really good luck getting that one. You're it's basically you're never to find it It's pretty common to have them as separate chips and then you you fuse the the data together and you get You know XYZ orientation. It's cool And you know, like I said earlier, you're not gonna get B&O 0 5 5 or 0 8 5 like any time soon Those are those are totally unobtainium So I got the accelerometer gyroscopes. What's interesting is I've totally not been able to get magnetometers I did get some list 2 MDLs, but not the list 3 MDL and the list 2 MDL is a plus minus 50 gals and the list 3 MDL is a plus or minus, you know 16 gals which is the same as 1.6 mila tesla so divide by 10 to get from gals to mila tesla And this is better because you want you want something that has you know good 16-bit resolution and Accuracy because the earth's magnetic field is much lighter than you know Magnet that you have in your hand and there's mainly two kind of magnetometers There's like the high-range magnetometers that are good for detecting magnets And then there's the low-range sensitive magnetometers that are good for sensing the earth's magnetic field So the the list 2 MDL is not a it's not a bad magnetometer for that But I'm also a little worried. I won't be able to get that chip as well other magnetometers I have I either haven't been able to get or they are the high-range types So what I'm you know, and then I'm not sure I'm ever going to get the 3 MDLs again I do have a you know big order in With ST, but it's just this you know, I think everyone's just totally crunched with this part shortage so what I'm going to do on this great search is I'm going to find a high-resolution select 12 16 18 20 bit Triple axis magnetometer that's I squared C because I want it to work, you know, I want it to be compatible not maybe not pin compatible, but it is as functionally compatible as possible so I can pair it You see here. I have the the chip next to the IMU for a 9 doff sensor, so let's go to dig a key and And let's search for so this is the part I'm looking for the list 3 MDL So let's just go there because it's always good to you know You start with the part you can't get and sometimes it's it gives you ideas of how to find the part you can't get So this is the part that you know if you put in that you want some it says, you know, I don't know 2059 I don't think it's actually 2059. I think what they're just saying is we don't know when we're going to get the ability to make this I think you need a particular kind of Fabrication technology which is superbooked So what we do wants let's go down here, and then we can use this to search so you want a magneto resistive active XYZ Xcelometer that's sorry magnetometer that's surface mount You know, I don't really I don't I'm not going to specify the range because I don't care if there's multiple ranges or one range The voltage supply I'm not worried about it's probably gonna be three volts Resolution I don't want to be too picky Package I don't expect to get the same package, but I do want it to be you know the minimum is it's a it's a magneto resistive active XYZ, so let's search Also, I want to be about the same cost the 3mdl is you know, basically one or two bucks So I want it to be about that price. I don't want to spend Like $20 on this part Okay, so output type So this is the thing that I'm going to select first because there's not a ton of options here Which is good actually there's only 10 That's very small So I think I want I squared C and SPI only So let's let's do that limitation all these ranges are quite good Remember the list 3mdl is 1.6 mila Tesla I don't want it to be much bigger than that because I want it to be again used for Earth Sensing so I don't want it more than like five, but all these are are quite good All these cover 3.3 volts, which is what's important to me You know, it's if it's lower great, but that's all I care about all them have 16 plus resolution So it's really good. So let's see what's available So there is the the ST ones. They're not in stock I think let's let's look at only ones that are in stock right now Okay, looks good. So we have a couple options here actually And they all look they all look pretty good to be honest. So there is From you know mem sick, there's a couple options from Rome There is an option with a lot of pieces But what I really liked is you know when I was like, okay Well, I'm probably gonna buy, you know 3000 of these because I'm gonna use it a lot of stuff When I looked at the price The price of these mem sick ones was like very very attractive and I know mem sick makes, you know, good components, too So this could be a good alternative. What I'll do is I'll probably make new Versions of all those IMU plus magnetometer breakouts and then when I can't get the list 3MDL You know, because there's people who have those the code already in their design We can always go back But as long as I have a lot, you know libraries for all them I think people can can switch pretty easily in case it's another year or two So there's two options here, but they'll look really good You're probably wondering, well, what's the difference between, you know, the MMC 5603 and the MMC 5633 They're both very similar Let's look at the MMC because I did Pull up these data sheets and I do this little trick where I kind of like Scroll down and I try to like I Try to get like the data sheets to kind of like be almost the same And then I kind of flip between them to see if I can see what's different and If you look down here, what's different What's different is on this one you see there's a This one has a I3C interface in addition to an I squared C interface So that's basically what you're gonna pay a little bit more for on the 5, 6, 3, 3 They're both actually pin compatible They are not completely code compatible. The register map is a little bit different But they are, you know, this is unfortunately it is it's a BGA. It's a WLCSP With 0.4 millimeter pitch, but if it only has four pins, I'm not as nervous about it I don't have to do a fan out like, you know, four pins mean that I can just I can just bring the pins out from each corner when something has Nine pins, you know, there's always a pin in the middle and that can be tough to get out But with four pins, even if it's fine pitch, I'm not I'm not as nervous about it So this one is a really good option. So I think I'm going to start and also I really like that There's 77,000 stock I'm probably going to start with, you know, making a systemic UT breakout for this MMC 56.03 so you can get Arduino and circuit Python and Python library code going for it and then You know, if that's good, I'll you know Just like connect it up with an IMU and like stack them one on top of each other and then like try twisting and turning it with our Fusion code and just make sure that it like works fine with that and if it does I'll make new breakouts and just, you know, tell folks like hey If you're waiting for this 9-dolph that has the list 3MDL and you don't want to wait Because the magnetometer is not an important part of an IMU like you want a good one But it's not it's not the thing that really affects the quality of an IMU the thing that really affects it is the gyro That's what's important. And so Matching, you know, the as long as the gyro is good as long as you match with anything That's a kind of reasonable magnetometer. You're gonna get good data. So This one looks good If you're if you're in the in the market for a magnetometer and you can't get one because you can't get one this one's cheap and available and You know, it's not hand solderable But it should be pretty easy to work into your pick-and-place manufacturing setup. That's great church