Hi, it's Jelly Bean component time again. In two previous videos, we took a look at Jelly Bean Op amps and Jelly Bean voltage regulators and references, so I'll link those in if you haven't seen them. So this one is going to be Jelly Bean comparators, and it's not going to be quite as easy. There's a few definite Jelly Bean comparators, but there's a few oddball ones as well due to probably necessity.

Anyway, let's get into it: A Jelly bean component has several criteria. One is it has to have pretty much been around a long time to become the industry standard part. Just the go-to part that you grab when, oh, I need a voltage regulator, I don't need an Op-amp I need a comparator. Don't care too much about the specs, I just you know that's the Jelly Bean one that you pick.

And when a Jelly Bean component has been around for so long, often 30 or 40 years, then it's of course, set. Uh, the sort of like standard specifications. It set the standard, uh, package, the standard pin out and thing which most other manufacturers follow. And that's the thing about Jelly Beans is that they should be available from different manufacturers.

not only the big name ones, but also like the ones you've never heard of, all the Asian sourced, uh, manufacturers, and everything else. If it's available from like five or ten different manufacturers, including the no namers, then you can be pretty sure it's Jelly bean-ish Now, before we get to our first comparator, you might be saying dave, I don't even need a stinking comparator because I can just use one of my spare Op amps that I've got lying around from my Jelly Bean Op amps. I might have had a quad package or a dual package or something like this. I've got one spare.

I can just use an Op-amp as a comparator. Well, yeah, nah, as we say here in Australia, Yeah, you can use it. but there are some traps. uh, for young players.

the main one being the speed of Op-amps They're just not that thin. uh, fast. and you may think, ah, what's the big deal? No worries, I'm feeding the Op-amp into a gate or something like that. A flip-flop Well, let me show you the trap.

for young players, let's take the Lm358, one of our bog standard Jelly Bean Op-amps down here. Frequency response: Op-amps are slow. at least the Jelly bean ones are. So you look at the slew rate here.

Okay, 0.5 volts per microsecond. So if you want to sli swing from zero to a five volts for example, unlike you would for like, a five volt comparator, then you're talking 10 microseconds. Um, to do that. And not only that, because it's an Op amp, it's not designed to be uh, driven non-linearly like this and have the inputs are and output slam like this.

You've got another thing called the overload recovery time. I'm sure I've mentioned this in another video somewhere. There's another 10 microseconds just to recover and then you've got settling time and stuff. These things are as slow as a wet week and not to mention other problems with Uh you might have diode clamping on the Uh inputs.

for example of an Op-amp which actually designed to protect the input well. That means they could have a limited Uh differential voltage range on the input and you can't like compare big voltage differences and stuff like that. You can come a gutsy there very easily. Not to mention the basic fact that an Op Amp does not have an open collector output like a standard comparator wheel as you'll see later, so you can't use them as window comparators to do your regular um, you know, or in function on the output and stuff.

It's just. you know it's not not the right tool for your job. Yes, you can use and I've used Op-amps as comparatives because I had a spare Op-amp available. But yeah, you have to be very careful.

But let me show you why the speed could be a problem: Input slew rate limitations on digital chips, which you might be feeding an output of a comparator into, for example. So I know we started out on a complete tangent here, but it's pretty important. so let's go. Um, like just a regular 74 Hc74 flip flop.

uh, for example, it'll be similar for other digital uh logic and here it is right here: Input transition, rise and fall rate. You're talking like four or five hundred nano seconds. So right there. your Op Amp is Not fast enough to drive just a Jelly Bean 74.

You know, Hc74 logic. So what does that mean? Well, if you've seen my previous digital logic, tutorial, videos and stuff, you'll know that flip-flops can get into a meta-stable state. Basically any digital logic. Be it discrete logic like this, it could be an Fpga.

They're going to have a maximum input transition time unless they're a schmidt trigger input, and a good majority of them aren't schmidt trigger inputs. So you've got to be careful. If you exceed that maximum input rise and fall rate, then your gate can go into a meta stable state and just go absolutely crazy and you wonder why your circuits are going Silly buggers. But anyway, enough of that.

What is the Jelly Bean? It is and isn't the Lm311. Sorry for all you 311 fanboys Or 311 fanboys. Um, it is the industry standard Jelly Bean component in that it's been around since September 1973. and yes, it is the industry standard.

but it's probably not the go-to Jelly Bean component for a single Op amp. If you just need one amp Op Amp in one package, you're probably not going to be using the 311 these days. I'll show you one shortly. But by definition, the Jelly Bean comparator is the one always has been to a lot of people always will be.

As with all these jellybean components, you should, uh, have them available in your Cad library for example, in like different packages and things like that and different uh, suppliers in in your bill of materials and supplier information and stuff like that. So you can just drag and drop these jelly bean components in. That's the whole point of these. You have them in your standardized component library.

Uh, I need a comparator. I'm just going to drop in. I don't care about the specs, I'm just going to drop in a jelly bean part. But the problem with the Lm311 it it has some good points and it has some not so good points.

The good points are that it actually has extra inputs, a balance and strobe input here, which we can talk about. and it also has what's called a floating output here or an uncommitted output. So this is what's called an open collector output because the there's nothing else internal. it's just got an output driver transistor like this and the collector is not connected to anything.

This allows you to do wire or configurations with your comparators. You can like tie all the outputs in parallel. You can get wire or wire and depending on how you configure the inputs and stuff and you can do a logic functions with the output and that's very useful. Uh, one of the main reasons why um, a good lot of probably the majority of comparators are open collector comparators like this.

But the Lm311 is special in that the emitter here is not tied. It's like essentially floating so that it's not tied through to your ground terminal like you'd get on a good majority of our comparators out there. So the Lm311 is still useful. Uh, for that, If you needed an uncommitted Um output like this, or a floating output like this, yet, the 311 would be your go-to thing.

So what are the downsides of this? Well, unfortunately, it's only available in um, basically an eight pin Um package. and most of the time, when you want just one, uh, comparator like this? Same with an Op-amp You, you know, and you go in Smd and you want small because you don't, you know you want to minimize your footprint, you'd want to go for like a five pin Sot package for example, instead of this eight pin. So one, because this has some extra balance and strobe and the extra emitter output like this, they just can't fit the 311. You just can't get it in like a five pin Sot 23 package.

So the 311 is not classified as a fast comparator. but 165 nanoseconds? Um, isn't too bad. It's not too shabby. Basically, we'll look at fast ones later and they're an order of magnitude.

uh, better than that, but you know it's You can get a certainly a lot, um, slower than this one. And then you've got the input bias and offset currents here. 300 nano amps and 70 nano amps. Uh, we'll look at low power ones later and their orders of magnitude are better than this down in like the pico amp uh region.

but you know this ain't too shabby for just you know. And if you're not talking about like real high impedance applications, it's not too bad at all. and it can operate from a single five volt supply. But the good thing is this is one of the high voltage Op amps we'll look at, uh, more later and it can do basically plus minus 15 volts so 30 volt supply.

but it works happily at regular, uh, five volt. but this is by no means a low voltage out comparative. We'll look at those uh later. and of course it's got decent drive output capability 50 volts, um, at up to 50 milliamps drive.

And this is one of the things with comparators is that you have the big open collector driver because you don't just want to drive digital logic. for example, you want to. In fact, one of the advantages of open collector like this is you might want to drive a relay coil you might want to drive, you know, a solenoid, you know, even a real high current. uh, lead at, you know, tens of milliamps, something like that, or even a string.

And the Um output voltage is capable of handling uh 50 volts, Uh, basically well above. uh. the rated supply voltage of the chip. Nice.

And this is why you'll find like one of their applications here. White goods, for example, like you might find these in, you know, washing machines and dishwashers that have solenoids and drive things and stuff like that. You might just use the good old Lm311. So really the only reason you'd use the 311 these days is if you know you wanted like a 8-pin dip package.

If you're doing through-hole or something like that, it's just fine. You can get it in so or you wanted like a balance. for example, you wanted to make this a bit more precision. You wanted to put a pod in there and tweak it so that you can tweak the offset voltage which is not that terrific in this.

Um, it's not that good because they don't tell you up the top in the battery specs, but it's not that bad if you take a look over here. typically a plus minus 15 volts, you're talking. You know, a couple of millivolts. Something like that could be as bad as 10 millivolts for example, over the full temperature range.

but you can actually put in a pot and trim that if you don't want to use like a real expensive precision Op-amp But then you've got to pay for the pot. and then you're going to pay for someone's time to tweak it. and uh, you know it's just like it's really old-school like 1970s stuff. So here's an example of using the balance there with the pot and everything.

and it's just you know, like there's just better ways to do it. These days you just spend the money and uh, you know, get a more precision Op amp if you need it anyway. The other function is the strobe which is uh, used as shares a pin with the balance pin. And what this does you need? An extern? You can't just strap it you need like an external transistor here because this is a current driven thing and it will actually disable the output.

so it allows you know a micro or some other digital logic to actually disable the output transistor if you want to, actually, uh, turn it off remotely or you want to gate it or something or strobe it as it's called. So once again, it's a pretty old-school thing, more obscure application these days to have like a strobe capability on your Op-amp But if you need it, hey, the Lm311 is for you. So what would be the go-to Jelly Bean single comparator these days? Well, you could argue. probably at the Ts 391.

This is uh, like an St one, but there are many other manufacturers this I'll show you in a minute. Um, and it's available in a sort 23, uh, some you know Dfn 8 for those who you know Dfn fanboys but very similar to 311. It's got 2 volt to 36 volt. Our capability can be operated from plus minus one volt supplies to plus minus 18, so you know it's really quite schmidt.

Um, it's got reasonably low current uh, 200 microamps and which is independent of the supply voltage, so it doesn't matter. So you know that's not too shabby. But this is not a low power Op amp. We'll show you an option for that in a minute.

Um, 25 nano amp Input Bias Current: Not too shabby? Um, Input Offset current: Five nano amps? Uh. Input Offset voltage plus minus two millivolts max. And once again, there are variations like A and B. You know, various versions.

So this, this is the 391 and 391a and this will vary between manufacturers. All these sorts of specs will actually slightly vary between manufacturers. In particular, things, like, you know, offset voltages and bias currents and you know, stuff like that. So just be careful of that if you're doing a drop in replacement.

But as with all Jelly Bean components, if you're caring about oh, I do care about the difference between two millivolt offset and five millivolt offset, then you know I want to. Can't I have to pick this manufacturer over that one. Then you're not really in the jelly bean category. You just throw it in there.

And two millivolts? Five million volts offset? Yeah, she'll be right. no worries. So the major specifications you're going to care about for a comparator are the input offset, uh, voltage. Just like up Op amps, they have offset, uh, voltages.

and if you have to really precision voltage comparisons then this could matter. But you wouldn't be choosing a jelly bean for this. So you know input like typically one millivolt you know could be as bad as nine over max, uh, temperature and stuff like that. And then you're going to have your input bias and offset currents.

And this is pretty much uh, due to the technology of the device. Is it the Cmos device which we'll look at? Or is it a Bipolar device like this one? and you can tell because it uses well. Where's the internal diagram? There you go. It uses bipolar transistors there.

None of that mosfet rubbish. Then of course the other thing you care about is your supply current. Your Icc here. this has got, you know, 200 500 microamps? uh, something like that.

So it's not low power. We'll look at those in a minute, but you know good enough. I mean once you start getting to a couple of milliamps, geez, that's a real high power joby. Now the input differential voltage.

We might have a look at this later, but uh, that matters because you can have like a real big like 30 volt range. uh, comparator. Yet it only has a small differential input voltage. so a bit of a trap for young players that one so that could be important.

Just keep a watch out for it. of course. The other biggie, uh with comparators because as I said, you usually want to drive relays or you know something, Grunty leads, solenoids or something is the output drive cable. This one not that great.

16 milliamps typical. They don't actually give you an upper bound maximum on that. I don't know why St aren't doing that. We might get it on another manufacturer, but yeah, I mean, you know, but that's good enough to drive like a relay or something.

And the other biggie, of course, is the speed of the Op amp. So the small signal, uh, response time here 1.3 microseconds. But as we saw before, that might be, um, too slow to actually drive like a digital logic for example. So you got to be careful.

But because this is an open collector one here, then it's going to be, uh, depended upon that's a poor resistor. The uh, external pull up resistor you pull here for your positive, uh, going transition. that will depend on the capacitance of your line and the pull-up resistor value. But that's the same with all open collector comparators.

So if you don't believe me that the 391 is available from different manufacturers, well let's go over to Lcsc here. which is like the Asian digikey kind of thing. 319 comparator? Whack that in there And uh, we sort by, uh, price down here and we get the Ts 391 from Utc. uh, Unisonic, uh, tech.

And then we've got uh, Rome, uh. I'm not sure if that one's if that's a T stop5 I'm not sure if that's the same high gain voltage comparator. I don't know. It looks looks similar, doesn't it? Then you've got the St Micro one here.

and then you've got the Texas instruments. You've got an on Semi one down here. you've got oh, no one to 2901 or we won't go into that whole, uh family. Um, and then you've got Tlv variants from, uh, Texas Instrument.

There's another variant from on Semi here, and well, you start getting into lots of different variants. But you have to actually be careful here because there's another trap. and here it is. Check this out, right? It's got 391 in the number here from analog devices, but it ain't the same look.

2.3 volts to 5 volt to 5.5 volt operation only. For example, the Tlv 1391, which you might think, oh, it's got 391 in the number. It's the same 2 volt to 7 volt open collector. It's not that high voltage range, so just be careful of that and I'll show you another trap in a minute where the same thing applies.

So just because it has the same digits in the number doesn't necessarily mean it's going to be an equivalent part. So yeah, you want to be careful. And after all that waffle, we finally get to the what I think is the uh, industry standard comparator out there. That jelly bean one that you're just going to use absolutely everywhere.

Which is the Lm393. Once again, it died. Dates from October 1979. old school, and as its name says, it is a dual comparator.

Um, so it's basically roughly equivalent to the 311, but it's available in the same Soa package, but you get two comparators for the price of one and it's pretty much the one you want to drop in if you don't use the other comparator. Meh, doesn't matter, Um, just you know. tie it off or leave the pins uncommitted and just use the single one and you might be able to hack it in later. One of the advantages of using a dual package.

so it's got 38 volt voltage rating, input offset uh, point? you know, 370? Uh, micro volts a bit. but yeah, you got to. you know, watch out for the spread of that input bias current. 3.5 nano amps? Um, it draws 200 microamps which isn't too shabby.

so it's not super low power, but you know it's low-ish It's got one microsecond response time once again, might not be fast enough for driving. Uh, digital logic stuff and things like that. but uh, you know it's for everything else. Yeah, it's good to go.

And as I mentioned before, there are like this, you know, 2903 series. So there are other manufacturers uh, like series numbers in there as well. Um, so they're basically an equivalent part and I won't go into the details, it's just yeah. same thing everyone just calls it the 393.

How Jelly Bean is it? I hear you ask. well put in 393 comparator into Lcsc? Um. 116. right? We sort by price here and uh, yeah, like down in like three cents? Um per? uh part? You know, 3700 in stock? Uh, 339 000 in stock, 210 000 in stock, right? 173 000? No worries, right? And we, it comes from uh, hands.

Chip Ones You've never heard of Htc, Hg Semi, Um. Zlunder, Id Chip Diodes Incorporated. You've probably heard of those. Um, you know, eg, Micro? Never heard of who's three peak? um, ones? He's in three point, right? And then, yeah, you know, even.

You know you go up to five massive five cents. You know you're into your own Semi and you know your real big brand names. I'm You know your diodes in cob again, and Texas Instruments are one is still down in six. You know, the sixth sense region for a genuine Ti? Joby? Um, and they're just available from the pool Op? You've got to see Poo Lop Pulo.

I think we've had those before, haven't we? I think we discovered them on a previous video. But yeah, right, it's all there. And just to prove there's no component shortage when it comes to Jelly Bean comparators, let's go to Digi Key here and search for Lm393. And here we go.

look at this. 1.4 million in stock on the shelves At Dgk, you got to pay? Well, look at this. almost 12 cents in thousand off quantity. You get a genuine on semi though, but you know, like serious stock right? And this is just a Digi key, No worries.

And of course it's the comparator of choice for vacuum robots. So here's this uh family comparison table which I showed you before with the you know, the 2903 and stuff like that and and the B version and also like there's 193 and 293 which is available in same with the Lm311 as well. and these are like just higher temperature range military components you can see like minus 55 to 125 degree range whereas your regular one here is like 0 to 70 degrees. but your B version minus 40 to plus Id5 for example.

um some of these might have different Esd human body model ratings and stuff like that and your offset voltages might be uh, higher. The only reason they're higher is because they're rated over like bigger temperature ranges. So go to the on semi data sheet. It just shows like the packages better and stuff like that shows the internal connections better than the Tir data sheet and this is the industry standard.

Uh, pin out for a dual uh comparator? of course you lose uh the strobe and offset balance capabilities you get on the three one one but like, if you're gonna like, these are cheaper. These are often. the dual is often cheaper than the Three One one, so you're just going to throw in the jewel anyway. Uh, because odds are if you're going to use one comparator, you might need another one.

But of course, one of the big applications for comparators is a window comparator. So you need those two Op amps and you need the open collector output like this so that you can just, uh, here it is here. The output is open collector so that you can just, uh, tie the two pins together and you can all the outputs and you can get make yourself a window comparator. Beauty.

And if the dual job is not enough for you, well, you can get the Classic 339 Quad comparator here. It is once again available in the 2901, the Three Two Three Nine, and the One Three nine. Uh, configurations. But it's basically, um, both the 393 and the Three Three Nine.

I know they're a bit confusing, but they are basically dual and quad versions of the classic Lm, Three One One, and once again dates back to October 1979. Old school. But the Three Three Nine? It's everywhere. Chili Bean As the good thing about the 311, the 393, and the 339 i think I've got that right is that the common mode input voltage includes ground, so it can be zero.

It can go right down to zero. so hence, you can use these as a single supply applications. and that's called ground sensing as well. so you can sense all the way.

you can compare all the way down to ground. But the downside is these are not what's called a rail to rail input Op amps. We'll show you those in a minute. So yeah, it can go down to zero volts, but you notice that it's um, it has to be at least 1.5 volts below Vcc, so it can't.

You can't compare voltages right up to the V to the supply voltage the Vcc voltage. So that's something, uh, to consider for these, uh, jelly bean ones. So let's now go have a look at, um, what you might use for a lower power, more lower voltage application. Now if you're talking about low voltage, r comparators, window comparators, window detectors, uh, you know, just general low voltage sensing and comparison applications, then you probably you might be looking at uh, the basically the same as the three one one, but it's the Lmv series and you might remember this from our Op amps which had a similar thing.

Well, the same thing is available in comparators as well. So the Lmv 33r1 is the single comparator. the Lmv393 It's the same as the 393, but you'll see how the difference is in a minute. It's the dual version and then we've got the quad version the 339, but it's Lmv in front of it.

Rv stands for voltage or low Voltage and it tells you right here. These are low voltage versions of the dual quad and single Uh comparators which operate from 5 to 30 volts. Before now they operate from 2.7 to 5.5 volts only, so I only feel like your 3.3 volt and 5 volt Ttl logic stuff, but that's a little long. It's everything these days, didn't it when I was a boy? But you'll notice that this is, uh, still uses uh, Bipolar transistors mostly in here.

There's one little sneaky bugger fed in there, but basically these are it's still a bipolar. It's not a Cmos comparator, i haven't gotten to those yet and it's the same open collector output, no worries. But it's just designed for different voltage applications, so we'll have a look at the specs so all of your parameters here. They're all very, quite similar to the Um, the Non, and just the Lm version that we got before, but the difference is in its sensing capability, which is, but the difference is if you power it from five volts here, it does have a better input voltage range, but still not rail to rail so it will be ground sensing.

so the common mode input voltage range does Go does go below ground, so that includes sensing to ground, but it'll still only go to 4.2 volts so still not quite rail-to-rail input, but these are better suited if you know you're working at 3.3 or 5 volts. you you know, drop this into your uh schematic instead of the regular 393 for example. But once again, be very careful with 331 in the number lmv331. Well, this is Ti right? Ti also make a Tl 331.

it's very different. Um, yeah, it's like the like 38 volt um, comparator. Again, it is not the low voltage jobby so just be aware. same number, but that prefix matters now.

Unfortunately, at this point all the ones were seen up until now. They are truly Jelly Bean Op amps. But here's where the wheels fall off the jelly bean billy cart and uh, pretty much you stack it into single sauce and maybe only like a two sources or something like that. Now um, all the ones we've looked at have been open collector ones and they've had limitations in terms of like non-rail-to-rail inputs.

They've had limitations in terms of speed and all sorts of stuff. So let's go and look at like a better class of comparator here. and let's go for the Tlv 370x family so 3701, 3702 and the 3704. You can also get these second source.

These are Ti, but you can also get them second sourced from St as well. They do the Tsr3702 and these are you know pretty decent ones. Even although I wouldn't call them jelly bean. these are kind of like the next step up in uh comparators.

uh for you know useful applications. As you can see here, these aren't nanopower, so they're low power jobbies. They're push pull outputs so no more open collector outputs. It can both push the output voltage high so it can actively drive it high.

You don't need an external pull up resistor to get the output. And of course, if you're driving relays and things like this, um, then this is not something that you'd be using. So they're available in single, dual N quad versions. uh, 560 nano amps per channel, right? So in none of this micro amp rubbish.

and like nano amps now per comparator input, Common Road Manage exceeds the rails, so you can actually go to Vcc plus 5 volts. So the input voltage range you can actually sense higher input voltages than the rail, and the actual operational rails can go from 2.5 to 16 volts. so it's very useful. Use them for like 12 volt applications.

so even if you used it for a 12 volt application, you could still sense 5 volts above that. So up to 17 volts? Nice. So this is a push-pull Cmos output stage. So we've gone from our Bipolar technology to our Cmos technology just like you do in Op amps.

This is the same for comparators, and there's probably hundreds of Cmos comparators out there, but I think you know these are good ones that you should have in your you know your parts library so you can just drop them in And the input offset voltage is nice on this, so you could almost call this like a precision uh comparator as well. 250 microvolts? Of course that's just typical. Like it could go up to five millivolts or seven millivolts over the full uh temperature range and stuff like that. but you know it's You know it's fairly tight.

Um, for your generic spec there. and now because it's Cmos, your input, offset, and bias currency down in the pico amps range. None of that nano amp rubbish. Uh, 20 to 80? Uh, you could you know, over the maximum temperature, but barely sneaking into the nano amp range.

but typically like under 100 pico amps? Nice. So really good for like, you know, high impedance sensing applications. And of course, because it's rail-to-rail output now, it can actually drive directly to the Vcc output rail so I can go to within 80 millivolts of the Vcc rail. Unfortunately, they're not perfect.

They're not the fastest to start things around. so yeah, seven, you know, ish micro seconds something like that. So if you need a really fast op amp, but these are, but that's the you trade off power consumption with speed of course. So these are like these are literally nano power, right? for a reason.

But yeah, and like for low voltage, Uh, low power. at like, high input impedance applications. they can go beyond a rail and stuff like that. These are just incredibly useful worth having in your component selection library.

And you can see that the St Semi has the internal diagram here. And yeah, it's like a mixture of Bipolar and bit fit input ones here. and of course the totem pole output there. or push pull as it's called.

None of this. If it just had like an open drain output, then it would just have this. If it says open drain instead of open collector, then you know it's a Cmos version instead of a Bipolar version. But yeah, so it's a push-pull output stage.

Now the interesting thing to note, if we go into comparators over on Lcsc, which of course lists all the major Asian manufacturers, they stock all of those. Now if we actually search for anything, but you know anything like really performance like fast for example. So let's go search for okay propagation delay, let's search for I. I would consider anything under probably 20 nanoseconds.

Let's just go 50 nanoseconds right? So let's go for a really fast comparator here. Okay, and let's search and see what we get. Under 50 nanoseconds for a comparator. What do we got? Ti Analog Devices Maxim Ti Ti Ti This analog devices all three Peak.

We finally got one. We finally got one. No, there's no. There's no data sheet.

We can't even look at it. but that is 12 nanoseconds There you go. But basically, um, look, these are all name brand stuff in the second page here. Same analog devices Maxim Yellow right? right? there's on Semi right.

There's basically, um, there's only that one manufacturer couldn't even Asian manufacturer couldn't even get a data sheet for that. makes a fast comparator under 50 nanoseconds. So there you go. if you want all this high performance stuff and then if you want precision ones as well, then you start talking all your major manufacturers.

The you know, the generic Asian ones that you haven't heard of before. They typically won't go into those sort of product areas, So that raises the question. why wouldn't they go into those areas And this might be. It's not just comparators, it's other uh parts as well.

You know, if you need you know, if you open up like a cheap uh, consumer thing and it's you know it needs some precision part. for something, you're probably going to find one of the major manufacturers in there. You're not going to find one of the no name Asian brands in there. If you've got any like really detailed info on why, leave it in the comments down below.

but I suspect it's You know it's process variation and they just you know, can't control or they don't want to, uh, try and control the uh, You know, the the processes to actually get and all the testing requirements and everything else that goes into manufacturing really high precision. Um, you know, high performance uh parts. They just generally don't seem to go into those sort of areas. It's really interesting, so if you wanted higher speed, then these are nano power uh type ones available.

Uh, like the 3701, 370 204. Then take a look at the Ts3021 once again. Um, I think this is only single source. Maybe you can get it somewhere else, but I can't readily.

uh, find it. But anyway, this is you know, a 38 nanosecond uh job here and it's available. So if you only need one comparator, it needs to be reasonably fast. And you know you need rail to rail and you need low voltage and stuff like that, then this is.

I would say this is probably one of the Pixar you'd go for. It's reasonably priced, does 38 nanoseconds. It only takes 73 microamps rail-to-rail input. It's got your push-pull outputs uh, 1.8 to 5-volt operation.

It's got a high Esd tolerance and you know it's not too shabby. Well worth checking out. And in terms of precision, um, you're talking input offset voltage. you know, like 500 micro volts so that's not too bad Once again, like over temperature.

If you want to, you know, play the absolute specs again. then it you know could be as high as you know, a couple of millivolts or something like that. But yeah, it's not too shabby. But here's where it counts.

Rise and fall times over here. Eight nine nano seconds. Now that microsecond rubbish. So you know these is a pretty nice little fast.

um, you know, low voltage comparator I really quite like. And then you got your propagation delays and stuff like that. It's you know, it's not too shabby at all, so well worth having in your parts art selection. But if you want kind of, when you think about like a fast precision comparator, um like oh, you know old-timers like me would think of the Lt1016 and that was, you know it used to be like the go-to one.

I don't know. Leave it in the comments down below. Um, I've got a date on this. No revision.

No, they don't seem to have a date on this. But anyway, the 1016 it was like at the time was like the sort of like, you know, a fast. It was the 10 nanos ultra fast precision 10 nanosecond comparator. That says it all right.

So you would spec this thing in. it's not cheap, it's not jelly bean and there's lots of other parts that beat it. Uh, these days, you know. But it's sort of like a baseline where so a lot of manufacturers will go.

even in analog devices. Lt will go. Look, it's an improved version of the 101.6 so it's ultra fast. you know, operates from a 5 volt supply.

It's got low offset voltage, no minimum input slew rate requirements as well, so it's not going to latch up. It's pretty stable, you know, and output latch capability as well so yeah, it's like lots of like precisiony type outputs and it's got complementary outputs so that's why it's in your 8 pin package because it's got q and not q outputs as well. Thanks for playing and a uh latch enable as well so you can latch uh the output. so like sample and hold uh type stuff and things like that.

It's really nice time to throw a curveball in. So we're definitely non-jelly bean now and this is just a bonus one because I think it's really cute. and it's fairly cheap too. It's like in the 25 cent category and you can get it from two different sources.

Very versatile part. It's the Tsm-102 and you can get it from Ti and Um St as well. So let's let's take a look inside here. So what do you get in this bad boy? Well, you get a dual amp, a dual comparator, and a voltage reference.

Would you like steak knives with that? Anyway, Um, yeah, check out this bad boy. So you've got two comparators in there, two Op amps and an adjustable reference all in the one chip. So yeah, you might have guessed what applications you know. Switch mode, power supplies, battery charges, voltage and current sensing over voltage, under voltage, window comparators, alarm detectors, sensors.

So if you're doing all sorts of analogy stuff, you can actually, um, combine. this is good part. bomb consolidation. Um, you know, if you need a jelly bean Op Amp and a jelly bean comparator and a jelly bean reference, this will do it all in one.

Or it might do it. You know you've got to check your specifications, so they're relatively low power. The Op Amps are 200 uh, microamps a pop, the comparators are 200 microamps a pop, and the voltage reference uh, Vrf up to 36 volts is adjustable. Can sink from one milliamp to 100 milliamps.

Just like the jelly bean references we looked at last time, you know 0.4 percent a grade. you can get standard grade versions. It's got latch up immunity for the comparators of course, which is what we care about here. Input common mode includes ground, but this is not a rail to rail one.

it's going to be open collector, um, output and you know it's a 2.1 meg um, Op amp and it's once again ground sensing and basically 3 to 30 volt. Uh. operation here for both the Op Amp and the comparator. So just you know.

Similar to the other Uh ones we've seen. So they've got separate specs for the Op amps. Separate specs are for the comparators and you know, one millivolt input. Offset voltage? Typical.

Um, they don't give you a typical offset for the comparator, but you know it's like in the same class as your three nine threes and your three One ones. and um, stuff like that, right? And uh, you input offset currents. This is not. uh, you know, it's down in the nano amp region.

You don't get a typical value there. You might get it over on the St data sheet or something like that and it's not got huge output current capability. Just you know. 16 milliamps typical.

doesn't give you like an upper one. Does it give you a maximum over here? No, it doesn't give you anything over here in the recommended Uh operating conditions for the maximum, so you know. but you know tens of milliamps, something like that. Good enough to drive.

you know, a relay or a decent Led or something like that. Yeah, unfortunately St is not going to tell you either. Um, yeah, it's like it's it's practically. Yeah, it's identical.

They don't give you a maximum value for your sync current for your uh, comparator. but yeah, you know. So yeah, it's it's got your reference. Uh, you know your adjustable reference like this.

Oh, application note: There you go. a battery charger using the Tsm-102 So yeah, like Tsm-102 Like there would be a voltage reference that you might use and then right. So you're using the internal voltage reference hence the pin numbers there 9, 8, and 13. You've got your adjustable Um output you know, divider here to set your reference voltage and then a Um series pass transistor in here to give you right a A like a high current precision reference supply like that.

So that's not too shabby. So they've got you know, an application circuit for a battery charger here for example. But you can use this thing for like all sorts of stuff when you've got dual comparator, dual Op amp, and a adjustable shunt reference in there. So I reckon that's a very nice little bonus part there.

Well worth having in your kit anyway. Um, I hope you enjoyed the comparators. I know that's been long and there's leave it in the comments down below. I know I left out your favorite comparator.

Everyone will have their favor. Oh, I use this little jewel Cmos job units the ducks guts and yep, leave it in the comments down below. I know there's thousands of them. So yeah, just calm down.

calm down. I know we haven't even scratched the surface of uh, comparators. What a 4539 like that? Well, there wouldn't be, there'd be more Op amps I guess than there would be. uh, comparators.

But yeah. anyway. um yeah, there's just an absolute ton of them. So anyway, I hope you found that comparatively interesting.

I'm here all week. Uh, if you didn't find it useful, give it a big thumbs up. As always, discuss down below and please tell us your favorite. Um, like Jillian did it like there's probably other jelly bean out ones out there, but you know, the ones I covered were pretty much the jelly bean.

But if you've got a good one that's available from like at least like three or four different manufacturers are, for example, then that can be considered jelly Bean, but also Jelly Bean in price and availability as well. Leave your favorite one down below. Catch you next time you.