 The great search bar at your body did you get an eight fruit lady? It uses her powers of engineering to find the things that you're looking for every single week Okay, all right this week. We have a special request. I don't think you got the grab your window computer, and I have the graphic up here Yeah Let's see here Yeah, you want over yeah, we'll pop really fast. Yeah, we saw this on YouTube so okay, so we had a YouTube comment from Cypher will co hi there. I would like to suggest request a great search segment. Please do a booster DC DC switching Regulator one with low quiescent current that is great for battery powered IOT device. I'm obsessed with battery Sorry with low power devices. Okay Yes, that's a good idea. It's actually quite hard to search I you know what's funny is it's the thing that everybody wants, but it's actually quite hard to search for and the reason it's hard to search for is There's Unlike linear regulators where the the pass-through current is Sorry linear regulators have you know, there's two components of the current you're drawing and the quiescent current and The the quiescent current does increase with more pass-through current, but not you know at low currents It's very steady It's like you know that if you're drawing a milliamp or less the quiescent current is going to be you know Five micro amps ten micro amps whatever and then you just add to that whatever the current going through it is because it's a linear Regulator the current is the current out. It's it's almost it completely identical other than quiescent Whereas for boost converters for DC DC converters Particularly boost converters, of course more current goes in then goes out because the you know There's more voltage on the output than the input and so by definition if you're drawing one milliamp You know if you're in your microcontroller system your IOT thing is is drawing say, you know one million of current It could be drawing if it could be so inefficient that it's drawing ten milliamps from the source battery and so Well, what normally we would call quiescent current is something you're looking for You're actually also looking for the efficiency at low currents and well I'll give you you know, there are again dozens and dozens of DC regulators and I'm not it's actually quite hard to find the exact You know, it's like you don't have you didn't have any specifications for the input voltage or output voltage or current requirements or whatever So I'm not gonna find the specific chip, but I'll give you Some hints and how to use the search to find Something close to what you want. So that's kind of the best I can do given the broad Specification required So First up, you know if you go to Digi-key, so let's go to my computer and You search for you know DC DC Control converters note that there's DC DC converters and DC DC controllers controllers usually you acquire having external Transistors I could the control transistors are so good for high current or we're high voltage or like other very weird setups 99% of the time these days people don't use controllers these converters where they regulate everything's kind of built in usually Utah's inductor maybe a diode a couple capacitors and you're and you're done so just note that there's there's two versions converters and controllers here and We're gonna go with the converter. There's ten times as many so That's another thing. There's over a quarter million different Converter so that's going to be a beast to find something but you know a couple things that I'm gonna quickly do to just pair this down is I'm gonna look for in stock only and Which is gonna basically take away 90% because a lot of chips are in stock And exclude marketplace. We're only looking at stuff. That's in stock at digi-key I'm also going to look for ones that only have a single output Voltage and they're active. So, you know, you'll be able to get them I'm assuming you know, it's just for somebody manufacturing. So you want it in stock now and also you want it to be available Also, you know, you didn't mention any voltage requirements, but I'm going to say You want a boost converter that gives you, you know from a couple alkaline batteries Maybe a lithium-ion battery up to five volts just that may not be what it is But hey, you know do the best I can And also, you know, it'll probably be a surface mount part Okay, so I want oh, you know what I picked modules by accident. Whoops I didn't mean to do that. Sorry. Oh, yeah, I sorry. I picked power supplies board mount. That's not what I wanted See made a mistake DC DC Converter I wanted the sorry I wanted the voltage regulators DC I tell you show how you can get down a path, but then how you can back out of it Yeah, sorry The DC DC converters is actually like plug-in outlet things cuz I was like why is this all like very physically large? I wanted the the chips themselves if I looked at the images. I wouldn't notice, but let's look at the The chips. Okay, so I'm looking at Voltage regulators DC DC switching regulators. This makes more sense. So I still want in stock And I'm going to exclude marketplace Okay, and I want active parts and I want ones with a Single output. I'm gonna make it simple One output. I'm going to look at only You know, there's ratio metric Step up whatever whatever whatever. I just want basics, you know, there's ones that can be step up step down I'm just gonna do step up only and not ratio metric Just every day So let's do that. Hmm. Um, I also want to have Adjustable fixed figure why it doesn't really matter I don't want Charge pump. I kind of want boost, but there's a lot of options. I think I'll leave this for now and I want it to be Positive only positive output Okay, so there one thing that you'll notice of all these searches that oh, and I think I Do want to be synchronous synchronous means you don't need a diet on the output usually makes a little bit more efficient So you'll note that because I required it to be in stock There's not a lot of options a lot of DC regulators are out But one thing you'll notice is that there you can select input means and output means and current outputs and switching and synchronous And whatever in packages one thing you can't search for is quiescent current another thing you can't search for is the boost converter mode so for low For when you're dealing with low currents, there's two modes. There's PFM and PWM and there's probably others I'm not thinking of but those are the kind of two popular ones And did you key even has a article? It's like, oh, I should I should you know if you want to look in more detail They have an article using PFM to improve switching DC-DC regulator efficiency at Low loads We've also covered whenever we covered boost converters, you know, they're often a pin that allows you to change which mode If you look here and here on the left, this is PWM mode, which is efficient at high Current, you know 100 milliamps 10 to a thousand milliamps. You'll get fairly good efficiency 1995 However, when you get to low efficiencies It plummets to 20% 30% efficient Which like totally sucks because if you're gonna spend a lot of your time at that low current and you want to be asleep for a Very long time you want good efficiency at low current. So the trade-off is PFM mode Which is on the right Which PFM stands for? Let's see pulse frequency modulation Which is actually a little bit like PDM it changes Changes the frequency to to adapt to the load You get much much better efficiency at low current. So you'll want to find something with PFM mode, but of course like you saw That's not a searchable thing on DigiGee and that's okay. I mean like with regulators. There are so many Specific weirdnesses that you're you're not gonna be this is why it's hard to search for them doesn't where I would actually say to go to something like TI and You know because I make boost regulators a lot coming to make boost regulars and use their search Defined parts and then go to DigiGee to see if they have them in stock. So For example, if you look for the step-up boost regulator section on ti.com You'll see they're like you want a controller. You want a converter and I want a converter and Here you can actually search You know, let's say I want from about 2.5 volts to maybe You know four volts max and I want five volts out and then maybe Quarter of an amp 250 milliamps, you know, so it's a Wi-Fi or Laura or something and then I Want to search by quiescent current Which they do have here the typical quiescent current You can find some good options So the only problem is these you know, I'll search for this one, which I don't Let me give you a key thing if you search for this part I didn't search for this particular one, but I'm like 99% sure. Oh, no, actually this one isn't stop This one isn't stock, but the the one I was searching for this one the 61 322 went into great circuit chips It's pretty much has like almost that it doesn't really have any in stock This is a different chip I think but for the regulator There's like 900 in stock of this one and the other versions that they don't so, you know that this is the challenge is like the You're not going to be able to When you go to the company site like your ti or maxim or or analog You'll get all the part options But then when you actually search for the part on to Q They may not be in stock and ti is never going to tell you like you can't search by what is actually available You can only like search by prices and stuff One of the one of the chips that did Make it in this list is the TPS 61023 which we actually have a breakout for and this one is a fairly high current output Another thing that You might want to look for is they have they do have like other things you can search for on ti so like light load efficiency is one thing so if you go to If this would be under features You can set things that you want like if you're like, oh, I really want bypass mode or light light load efficiency You can see these parts and then you know you can search for like this is you know at six micro amp quiescent Current part That's the part I was searching for before Yeah, so you can see you know what sorry you can see the sorry the quiescent current here and switching frequency max and min because again usually there's multiple Frequencies you can switch at and also put into pfm mode and then You can go back to digi key to actually buy it and see if it's in stock The other thing that I did is if you do want to Not go through every factory and search for like the different parts within like the ti or max and brands Is I did do a search where I Just sorted by price and then I looked like what was in stock and what was available and I did notice that there were a lot of These this part which I actually kind of liked was named low low power boost converter And it was available in a fairly easy to solder package and there's a lot of them in stock Which was pretty surprising and there's even a Featured product List of this I don't know if I covered this on an MPI, but the reason I thought this was interesting is it has a Input to output bypass feature so basically you can turn off the DC converter and have the input Current input voltage go to the output. So you don't have that yet I don't have that boost converter in efficiency. You basically turn it into a linear regulator if you have a chip that You know, and this is something we did cover this and I am PI there There's this idea of like okay if you have something with a radio because you're using IOT But your radio you can turn off your radio and run the whole system at a lower voltage like two volts and then Turn on the boost converter to put it to high voltage mode So then you can use the radio at a higher voltage and get more current output That's a good trick to get the low power Savings of having a lower voltage lower quiescent current because it's in a pass-through linear mode And then when you ready to actually use Wi-Fi or lower Bluetooth You kick this up to five volts or three volts or whatever you need to get that extra voltage lift Turn on your radio do your transmission at a high voltage high power output And then when you're done again go back into a low power mode. So I thought that this was kind of neat this also has a Sticks a little small but Has a automatic PFM PWM operation so that's another good sign if you want to use Something with low quiescent current and also has 4.5 Microamps typical quiescent. So even though this wasn't you know, I was kind of looking around and seeing what chips were available I was thinking if you're a you know a beginner especially And it's available in an MSOP package, which it looks like it is This would be easier to solder than a lot of the BGA packages and it looks like it's designed for IOT So this might be a good chip to check out especially since they had a lot of these in stock you can pick up the mcp 16 418 and family There's there's a bunch of these. There's one fixed and adjustable and I think you know various voltages So yeah, check these out. I think these are these are pretty cool These could be a good a good option for a you know, fairly inexpensive. It's about a dollar a piece IOT ready low quiescent current auto PFM P, but PWMO DC DC converter So I'll try them out if they work out for you. Let me know All right, that's great. Sure. Yay