Hi. This is Adam Grula with Texas Instruments Boost Converter and Controller Solutions Group. And today I'm going to be talking about the LM5155 and the LM5155/1 boost controller family, and some of the features and advantages to these devices. The LM5155 and the LM5155/1 are boost controllers. So there's going to be an external set driven by the internal 1.5 amp gate driver. We have a wide input bias range of 3.5 to 45 volts, so a very wide input range.

One of the key features for the LM5155 family is going to be the switching frequency, and the ability to switch all the way up at 2.2 megahertz. This allows you to avoid any EMI band that you're trying to avoid, most notably the AM band. But there may be other frequency bands that you're trying to avoid. We also have the ability to synchronize to an external clock, if you would prefer to do it that way.

For both the LM5155 and the LM5155/1, there is both a commercial version and an automotive Q100 grade version. And the key difference between those two devices is going to be the packaging. The commercial version is going to come in a standard 3 by 2 WSON package, and the automotive version is going to come into a 3 by 2 WSON package with Wettable Flanks. And what I mean by Wettable Flanks is the normal, no lead package is going to look here on the left, we have the standard no lead. And then on the right, we can see this cut-out here that's plated. And what that's going to allow is for visual inspection of the units without the need for the use of X-ray. So that is the key difference from a package perspective, between the automotive and the commercial versions of the LM5155 family.

Another feature I'd like to highlight is the hiccup mode short circuit protection. And that's going to be the key difference between the LM5155 and the LM5155/1. As you can see here, the LM5155 is going to have the hiccup mode short circuit protection disabled. The 5155/1 is going to have it enabled. And how our hiccup short circuit protection works is it's going to detect when you have 64 cycles of current limit in a row, if you're consistently hitting that current limit. It's going to shut the part down for 32,768 cycles. And then it's going to try to start up again. And it's going to see if it is still experiencing that over current situation. In which case it will shut down again. And if the situation is resolved, it will continue switching as normal.

I'd like to highlight that we need more than seven consecutive normal switching cycles to reset the counter. So when we say 64 cycles of consecutive current limit, it's going to need more than seven cycles normal to break that pattern. So we can see from this waveform here, the devices switching normally, the Vout is high. And then at this moment, a short circuit appears, a hard short appears on the output. And so the device shuts down for 32,000 cycles. And then at the end of that, the soft-start is pulled low. It starts starting up again, and the short circuit is resolved at this time. And so the device continues switching normally. So this allows it to have some fault protection built into the device, and then this is optional, which is why we have the two versions with this either disabled or enabled, depending on whether you would like to include it.

One really cool thing about boost controllers in this format is their ability to be used in multiple different topologies. So you see here, we have five different typologies. And this isn't even including a standard boost format. So the real flexibility, a lot of options here. So we have, for example, isolated flyback or non-isolated flyblack. It could be done with primary side regulation and also a sepic converter, which is a single ended primary inductance converter.

And so this is going to have two conductors wound on the same core. And this is going to allow for sort of a buck boost type converter where the input can be both higher and lower than the output. And because these inductors are both on the same winding, they're not taking up as much board space as some other ways of achieving a boost might. So a lot of really cool topology options with the LM5155 family.

And to go along with those topology options, we have many different EVMs. We have three different EVMs for each of the different topologies that you might be looking at. We have a boost EVM. And since we have the stats for that here, with 6 to 18 volts in with 24 volts out at 2 amps. And that one is going to switch at 440 kilohertz.

We have a flyback EVM. Now this is an isolated flyback EVM with a wide 18 to 36 volt in, and a 5 volt, 4 amp output. And the last EVM is the sepic EVM. This is going to take a 5 to 42 volt input, sort of like you were working directly off of the automotive battery. And that's going to put out 12 volts at 2 amps. And this EVM, the sepic, is a 2.2 megahertz EVM. So if you're interested in that aspect of the design, that EVM has that built in. We have a lot of tools and resources available to help assist you in designing with the LM5155. And so I've included a direct link to the tool folder here. But just to list some of the tools that we provide to help you make your design as easy as possible, we have a Quick Start Excel Calculator, which allows you to input a lot of your parasitics, a lot of your requirements. And it tells you how to set up the compensation loop appropriately. Very helpful tool.

We have PSpice models, we have TINA models. And we also have TI's WeBench Designer, which is a really fun and easy way to get a setup going very fast. It is very intuitive to use. So all very helpful ways to set up. We also have an app note on how to design a boost converter. There's also an app note for flyback and sepic as well. So a lot of options, a lot of tools to help assist in designing with this device.

We also have TI's reference designs. And TI's reference designs are something that I think is really cool, and a really interesting thing that we do. And you can see here, there's over 13 reference designs using the LM5155 available at this moment. And also a really wide variety in the topology with single output booths, multiple output flybacks, single output flybacks, isolated flybacks, and sepics, multiple output sepics. So a lot of different options, I've got a list here. In case something is sticking out to you, we're not going to talk about all of them today. But a lot of really cool things that you can do with the LM5155 family, and I think this is a great way to show that.

The first reference design I'd like to talk about is TIDA-020013. And this is a reference design for Automotive SPD-SmartGlass driver. So where the LM5155 fits into this system is it's going to work directly off the automotive battery, that wide input voltage. And it's going to output 66.7 volts into a switching cap voltage tripler. And that's going to provide the 200 volt rail for this application. I also like that this reference design highlights the 2.2 megahertz capability of the LM5155 in order to help reduce the EMI. So it's a very cool reference design, a lot of great things going on here.

Another reference design I'd like to touch on is TIDA-050023. And this is a IEEE type 3 power over Ethernet reference design. So a very cool reference design, providing the isolated flyback for that 42 to 57 volt range of power over Ethernet supply, for stuff like a network camera, for stuff like a wireless access point, any situation where you have a type 3 level power for isolated flyback for your power over Ethernet. This design is a really cool implementation of the LM5155 in a flyback capacity.

All right, thanks for watching. You can find more information about everything I've talked about today on our website at ti.com/product/lm5155. Thank you.