 Hi, I'm MPI. Hi, I'm MPI, Barty. Bye. Did you key this week? It is Analog Devices. Legata, what is IonMPI? New product introduction of the week. I'm glad you're asked. This week's IonMPI is going to go long. It is the LTC 4332 linear tech, which was purchased by Analog Devices. So it's Analog Devices, but sort of the LTC. But still, the quality and reliability of linear tech, they make luxurious electronic components now available at Analog Devices pricing and distribution. And this one is long because it is a long distance SPI encoder extender, which is, and I always love to put cats in these photos. So here's a long cat. So this device, it's an SPI extender. And we stock a similar chip, the LTC 4311, which is an I squared C bus. It's not like an extender. It's like an active terminator. But it's kind of the same family of like, usually I squared C and SPI are protocols that use on a PCB. They're meant for short distances of like 10 centimeters at the most. They're meant to go fast. They're meant to just connect from one component to the other. Maybe you'd have a short cable, but they're not meant for long distances. But sometimes you need to have long distances. So what's cool about the LTC 4332 is it's like a transparent, differential SPI extender that can go up to 1,200 meters, which is 12 football fields. I still love using football fields as a measure. So very, very long cabling. You're not going to get the full 2 megahertz max speed over it. We've got like 50 kilohertz or something. But still, it's pretty amazing to be able to do SPI over such a long distance. So the way this works is you need two chips. One is the controller and one is the peripheral. And on the left hand side, you see the controller. You get the SCK MISO MLC pins. That's like the data in, out, and clock. There are four peripheral select pins, SS1 through SS4. Note that SS4 is for the chip itself. So you actually only get like three chip select pins, which is on the other side, you can have up to three SPI devices that you can address. So it's like you would have it on the other side and then you would have like a display and then maybe an SD card and then maybe a thermocouple all on SPI. They can share those pins and they each have their own chip select pin. And then in between, and there's also an interrupt back. So you can have one interrupt line go backwards to alert you when data is ready and stuff. And in between, you have cat five, cat six cabling. So twisted pair is differential and the chips and code the SPI commands over the differential pair for TX and RX. And so you can use like your standard long ethernet cords, which are low cost and reliable. And then a link light lets you know that they're connected. So really easy to use. What's nice about this, a couple of little details that I saw that I thought were really well designed. One, I like that it's like transparent, right? You just you connect it up and the controller and the peripheral have no idea that it's going through this long differential link that's handled for you. It can do all four SPI modes because I know that there's some sensors and devices that use, most things use mode zero, but some use mode three or mode two or mode one. And it can switch between the two. So it will dynamically do the right thing, even if you have multiple different states, sorry, different modes of SCK polarity and latching. As long as the chip select line is active low, it'll automatically do the right thing for all your different peripherals on the opposite side. In the middle is this differential protocol. It's not published. It's like some whatever proprietary protocol. And you connect one to the other so you can't have multiple like peripherals on the side. Like it is one to one. They have some limitations on how much your ground can flow. That I think has to be within 25 volts. You do have to select the speed. And I think I'll show that later. But the speed tells it how much to overclock the differential link, which will determine your max bandwidth, which is like your max bandwidth, S clock speed versus the distance. So it's like a trade-off of how far you can go versus how fast you can go. You can't go the highest speed at the longest distance. It's inversely correlated. Okay, so this is the inside of it. There's the encoder and decoder, the link, the SPI pins, the FIFOs, which we'll talk about. The FIFOs actually matter when you're doing receiving. The link light and there is, the device itself is also an SPI peripheral, which you can configure and registers, although you don't have to. So the link light, I thought was kind of like a nice detail. So just like Ethernet, when you plug it in and it detects that the other side is connected and LED will go on. And it will also like make sure that you matches the right speed. You also query it over SPI if you don't want to like use the LED. The link speed, like I mentioned, you can use two pins or you can set it with the SPI registers. So there's eight levels and each one, you can see a second to the last column. It goes from two megahertz down to 25 kilohertz. And that will change the max length of cable from 100 feet to 1200 meters or more. So it's one of those things where it does depend on your cabling, your power supply, is it outside, what is the noise like in the area, your differential grounding, whatever. Try the, you know, probably over specified it, but maybe go like one level less. So if you need to go 250 feet, maybe it says use speed index five, but maybe it's speed index four. So you have a little bit of leeway. And of course, you'll want to go as slow as the slowest device. Like each device has to share the same SCK. So if you have a device that is, can't be clocked faster than 100 kilohertz, you're gonna have to set the entire bus to 100 kilohertz. Okay, next up, oh, so there is registers. It doesn't seem like you need to use these. A lot of it is just like reporting on faults, failures. You can change the speed index, overflow, underflow and word length. The word length has to do with the latency. So there's only one thing you just have to watch out for that might affect your firmware programming. So if you're only writing from the controller to the peripheral, the data is transmits, you know, transparently, but if you're reading data in, because it has to read the byte and then transmit it out, because like, you know, if you use SPI, usually you clock things out, but then you can also clock things in on the same clock and you'd have it be both mostly and me so active on the same SCK signal. Obviously it has to get a byte at a time and so it's gonna be one byte behind when it reads data. Data written is gonna be done on the clock because it can like send that byte at once, but as it reads it in, it's gonna be delayed. So your firmware might have to, if it's reading from the SPI interface, it'll have to drop the first byte and then from then on it'll be synchronized. So, you know, just something to watch out for. If you are reading data, like there's a lot of sensors that don't, but if you do, you might have to change your firmware a little bit just to like be aware that the first byte gets dropped. And then you can get an eval board. I like this one because it's like breakable. You can see in the middle that you can break apart and wire up a six cable and you don't even need like an ethernet connector. And then in between, I think it's like a PMOD port. So you can just like connect it to your ready to go PMOD devices and the chip is in stock. So if you want to purchase it, yeah, you can get it. Don't forget, you'll need two, one for the transmitter and one for the receiver, but then I'm gonna make a breakout board for this chip. I really like it. I like the LTC 4311 for iSquirtzy. It's been a great expander. It lets you take iSquirtzy up to, you know, a hundred feet easily with ethernet, but this one, because it goes over differential length, it's gonna be again, 1200 meters or more. Yeah. One of the cool things about this NPI series, it's new product introduction, often or sometimes, or at least now that there's stuff, when you see it here, that might mean more work on a breakout. So it's a little bit of coming down. Well, the new product for this week, the MCV 3421 was two weeks ago's iNPI. So I liked it so much. Circle of life. And I liked it so much, I made a breakout board for it. All right. That's how, you know, I got a seal of approval. That's this week's iNPI. Hi, I'm a PR.