Hi Just a quick follow-up on this Vada 15-minute Nickel Metal Hydride battery charger I looked at in the previous video, did a teardown and kind of reverse engineered the the main switching topology and charging circuit for the batteries and things like that and a lot of people wanted me to what follow up and actually probe this thing and see what's happening here because one of the outstanding issues from last time I didn't have time to look at is how they were actually measuring the discharge current for this thing. We knew that the DC to DC converter was basically putting all the batteries in series and there was a shunt measurements shunt resistor down the bottom down here and we also knew that by nature of this dual MOSFET configuration for each battery cell here. So here's each battery and there's a pair of MOSFETs across each one. And let me show you out the switching arrangement, how they can switch cells in and out depending on which of these MOSFETs they turn on.

So if you turn on the top one here for example, then you're going to charge the battery. Okay, so it's going to go through there and around down to there, but if you turn the bottom one on, you can completely bypass that boom and go straight down to the next one. so effectively they can switch in and out any one of these cells depending on the arrangement of these MOSFETs here and it's rather clever actually. I Like it.

it's a nice implementation. Now for this example: if you have this: MOSFET here the low MOSFET turned on and your bypass in this cell. What happens if you actually plug in the cell? Well, nothing because the body diode inside here okay, will actually be reverse biased. So the battery.

This is the negative terminal of the battery positive terminals up here. So the cathode of the body diode here is going to be positive with respect to the anode here. So therefore, that diet the body diode is reverse-biased And because you haven't turned the gate on, that gate voltage is zero because it's an N channel. MOSFET then no current is going to flow the battery at all and all you've got over here is just a sense line.

So Bingo! You just alternate between those two fits and you can turn each individual cell off and on. Same here. If you turn this one on, you can bypass it. Now let's say you only plugged in this battery here for example.

Then okay, then it would detect that there's a voltage on here. So the micro controller through the analog to digital converter is always checking these sense lines here and it detects oh, you just plugged in that battery. Okay, I will switch on this MOSFET and Bingo will charge that battery and then nothing plugged into the bottom one was. So return on this FET and Bingo.

Current flows down through the current shunt resistor and we can measure it now. of course. One thing we don't know is how they're actually doing the discharge. Let's say you had battery plugged into this third position over here and it detected it.

Okay, and but you put it in that discharge mode because it's got various. It's got charge mode discharge mode. It's also got test mode as well, which will discharge the battery and then charge it so it can measure the battery capacity. Get the accumulated charge, but you know if you turn both of these MOSFETs on, then well, you're just kind of short out your battery like that and well, you know that's no good you need to have.

How are they actually measuring it? Because we in the teardown of this thing I couldn't really find any current sense resistor. So they must actually be switching it on and possibly using this current shunt resistor down here like this. So they might be actually discharging them all in series just like they're charging them all in series and then calculating the discharge current based on the differential sense voltage across the cell here. Because you'll notice here if we go into discharge mode.

Bingo! We've actually got a slightly different discharge current for each one, so kind of doesn't make sense. If they were all being discharged in series like this, then you know you think they'd just measure the one, our current and then it would be same for all of them. But maybe they're just calculating this and they're actually multiplex in this direction switching individual cells like off and on and actually measuring things like that. So what we want to do is actually get out the scope and actually have a look.

If this thing is truly a constant current charge, we'll look at the charge first. Is it actually a constant current charge? Or do they actually do multiplexing and switch these MOSFETs off and on? So let's take a look with a scope now before we just go in here willy-nilly and actually hook up all of our channels because we've actually got eight MOSFETs on here. And ideally I'd like to actually get eight probes on there. but we've only got a four channel scope here.

but we do have our logic analyzer. So what I want to check first is just to see if the MOSFET drive signals on here are actually are digital and what signal level they're at. So what we'll do is we'll probe one of the MOSFETs here I'm doing a bottom MOSFET at the moment. so let's have a look at the bottom and bingo we're at five volts per division.

Five Ten fifteen, we're driving these MOSFETs MOSFETs with 15 volts. That's actually not surprising given that you really have to turn these MOSFETs on hard really drive them hard to get the lowest on resistance up possible so you get minimize the loss in them the power dissipation in them because they're only a little so8 package is tiny I think someone may have actually asked that question. You know, how do they get away with you know, eight amps charging on this thing with little SOA packages? It's because the on resistors is is incredibly low so they're driving with 15 volts. Let's check the upper.

MOSFET Now probe the upper mosfet. It's no. it's sitting down the ground. it's sitting down there at ground.

Nothing doing there at all and it should be identical for all the next channels. this is the well channel three here. 15 volts once again and they're all the same And that makes sense. When you've got no batteries plugged into this thing.

you want this bottom mosfet turned on so that you basically bypass in each cell. As we mentioned before, you don't want to be turning the top when you only want to switch on the charge to a battery when you detect that there's a voltage across there. I'm going to use my logic analyzer probes here. These are the new keysight ones.

Real tiny compared to the the huge ones that they actually had before. This is my new 3000 X-series Art Touch oscilloscope which Agilent replace my existing one with. Very nice, Very compact I A Rather liked those and pretty sexy. Now when you're probing something like this, make sure you turn the power off first.

And even using these very tiny easy hooks here, there is still the potential to short out between the pins. So yeah, you don't want to shoot your gate pin out to your source terminal there. That could be bad news. and you don't want them flapping around in the breeze either when you're like because I'm gonna have to probe some analog some other stuff on here - I know I might need to get in there.

But anyway, for now, for the purposes of this experiment, got to put some batteries in here. Just want to have a look at all eight gate signals. So I've just taped those down so they're not going to flap around in the breeze and accidentally. you know, like if I put any accidentally touch these, they're not just gonna fall down and accidentally short out.

And there's no worries with the input voltage range of these digital channels either. They're plus minus forty volts are capable. Just set it to white CMOS trigger in here which is 2.5 volts. Whatever.

Good enough I Could I should actually change that user threshold again. A touchscreen here contain chains that use the threshold up to you know I don't know. Eight volts there we go I'd only goes up eight volts maximum. that'll loop.

Actually, there was a trap for young players here if you read the specs for this for the digital channels here, sure it can accept up plus minus 40 volts, but the dinette the input dynamic range of these digital channels is only our 10 volts around the threshold voltage. So whatever threshold voltage. is set. So if we had 2.5 volts before in theory, well, according to the spec sheet, then the maximum input dynamic range would only be 12 point 5 volts.

But it probably still work. But yeah, yeah, that's not terrific. So there's a trade-off there between the usable dynamic range and the maximum input threshold voltage versus maximum input voltage versus your threshold voltage. How nasty! Oh god.

don't want that bloody touchy-feely scopes. And I'm sorry that it's next to impossible to get all of this in one shot. Inserting this, the screen at a reasonable resolution and the schematic as well. Anyway, I've got the eight digital light channels here and they're actually as per this schematic here.

So channel like a D0 at the bottom. Here is this lower MOSFET than channel one, two, three, four, five, six, seven eight. So we've got it switched on and as you can see the the lowest, the lower MOSFET for each one is actually switched on. So what I'll do is I will high switching on being high that is.

and let's plug in a battery and we'll see I'll plug it into the bottom one here. Okay, so we should see the these two MOSFETs which dd0 should drop low and d1 it should go high. So we're switching on the upper MOSFET to charge we're and we're turning off the low on MOSFET which is a disabled So here we go. Bingo There we go.

It just switched. You saw it. Hey hello, hello. We have ourselves a pulse that's walking away from us.

This thing looks like it might be. Well, it's switching off. Hmm. now.

I've got this at a low time base that's 200 milliseconds per division. So I'm not triggering off anything at the moment. it's just freerunning. Let me plug in another battery.

Okay, I've plugged in a second one and there's something happening. Hey, look at that. That's interesting. Let's try and capture at the moment.

I'm just free running I need to trigger off these digital channels so will trigger off the adizero down here so we can just go into trigger source and then we can now choose d0 down here. So let's let's trigger off d0 There we go and we can in that out there we go. That's interesting. Wow and I suspect if we put in the third and the fourth batteries, we'll see some extra stuff happening up here.

So I'm not sure of the time period. It's probably like a second or something, but I think it might be us switching those off every second. Plug in all four batteries. Let's switch this puppy on and see what happens here.

We go There we go. That's something convoluted happening here across sight. Well, except for the fourth channel. So I don't know what happened, what's happening in Channel 4.

Maybe it's not charging, huh? There we go. It just had a Dickey contact. but as you can see, they're switching something in there. so let's turn that down to wha.

Well, 200 milliseconds per division. Let's see if we get anything. No, let's turn it down to 500. There's got to be a period there.

There we go. One second. there you go. Interesting and what I'm just doing here is actually our label in the channels.

I've made them bigger to fit the full screen because we're just looking at the digital here and I like the new work wordy keyboard on this thing because we can just go in here and then bingo with the touchscreen. we can just you know, type in anything we want. What I like is that we've got an auto increment function here. so I can select I've already labeled this bottom one.

Bypass one bypass - it automatically incremented to bypass three. We can apply the new label and then we can go. Okay, we want. We've already got those three that 1d6 apply a new label BAM - easy.

Okay, so that makes it easier. bypass channel one and charge channel one and so on for the other channels. And as you can see, we have 500 milliseconds up per division. So each second is a new cycle.

So I just realized I labeled these different - what? I've got on the schematic here. Oops. Anyway, let's just like number one down here. Okay, for the first 500 milliseconds, it's actually bypassed that.

battery is not being charged, and then for the next 500 milliseconds, you can see that it does charge because then the charge goes high, charge, line goes high for 500 milliseconds, and then of course the bypass. These are always alternate ones. I Don't think there's a scenario where you're going to have both that charge and you bypass on at the same time because be shorten your battery out So as you can see, they have for the first 500 milliseconds. number one, battery is on, number two is off, number three is on, number four is off.

so they're doing two at once here and then alternating between them. But we've also got this little data that's going on in there I'm not sure what that business is that might have to do with the measurement, but whatever it's doing in there for 20, 40, 50 milliseconds, that's not a coincidence I Think that's precisely 50 milliseconds. something's going on in there. Anyway, You can see how there always are alternate for each channel.

You'll never get both of those MOSFETs on at the same time. The ones high here, ones low here. And here's a limitation with the memory on this scope. even though we've got 4 Meg sample memory.

Okay, but because we got such a slow time base where look at, you know this sample rate for our digital channels 50 K samples per second, Right? Because we're capturing like you know, two seconds, we've got like what is it? You know, five seconds worth of data there on this thing that we're actually carry. And when we actually go in, there's a limit to how far we can see that it shows a block because that's one entire sample like that. So there's a limit to what we can see there to get around that you would need either a deeper memory our scopes slash logic analyzer. or you need a logic analyzer with that sample compression.

Or you could do it using segmented segmented memory as well. Okay, so we figured out what it's due in charging. It certainly is multiplexing these batteries. Let's now turn it back on I'll put it into white discharge mode and see what happens.

I'll do this off camera cause it could get fiddly. Hang on I Got to move the camera All right. Switch it on. we're in charge mode.

Excuse me. Discharge. There we go. We're discharging all four batteries around about 400 milliamps.

what's going on here? Let's run it. Come on. you can do it. Hey look at that.

so that's really interesting. There is not. Yeah, we're definitely updating. There's nothing updating there I'm at 500 milliseconds per division unless it's doing it out at 10 seconds maybe.

I Can you know leave a like that? But I know we would have. we would have seen something. It looks like they're all the bypass fit for each one is on. Okay, so let's have a look at the circuit arrangement, but it's not doing any multiplex indirect jury.

not discharged. Well, that's damn confusing. We've got the discharge MOSFET are on for each one of the channels and that's the path that would be taken. But as I said, because the positive terminal of the battery is up here, the body diode of the MOSFET is switched off here here, here and here.

So like, where is the discharge path, Where is the discharge path from this battery, Where is it going? It can only go two directions that way or that way and if it goes this way and yeah, it's there could be something over on this sense line here. that's you know, pulling it down and you know, allowing current to flow through. and but like me, where's the other end Then are they sensing this resistor? I Couldn't see any sense lines connected. any like differential lines across that resistor and then even if you did do that if it was flowing this way, but somehow, well, how would you discharge your triple-a Because you're triple-a is connected here.

So like I And also we're talking like half of what as well because it's like 400 milliamps discharge, right? So that's in the order of half of what that's got to be dissipated somewhere. And by the way, I have checked the output of the DC to DC converter. It's basically it's zero So but I don't see a discharge path here. How is current getting out of these batteries? The top MOSFET is switched off and yes, it's not just the digital channel.

I Did actually get back in there with a scope and did actually check and the gate voltage of these upper MOSFETs is actually zero. so it's not partially turned on or anything like that. Anyway, let's go back to charging, shall we? I don't know what the discharge thing is happening there, so let's just I can just reset the damn thing and we will go back to about 500 microseconds. That's no good.

We'll go back to our 500 milliseconds and what I want to do is just take out a battery or two. And so there we go. So there's only two batteries being charged at any one time because we've got our four amps discharged instead of eight. So let's take out his top one.

What change have we got there? We go. We've definitely it's bypass. It's switched into bypass mode there, All right. Yep, there we go.

It just took time to update. so let's now take off. It doesn't matter because there there doesn't matter which order. so we can take out the top one here just because I've got access to it.

and let's see if we've got what happens when we got two batteries. Bingo on for the full period. So there you go. That's the eight amps.

That's a difference between the eight amps. and the four amp charge. Now they're basically both on for the entire period. and by the way, I have actually tried to get in there with my tener with my meter in tener mode and actually measure the charge current.

but it looks like the drop is too much voltage drop in there and you know Jude the leads in the burden, voltage of the meter and everything else and it just it just does not charge. So yeah, it's tricky business sort of. You know, if you want to measure the current here, you've got to do it right. You've got to set up everything correctly and well, you know you can't just barge in a meter and expect the measurement because you know the safety cutouts in here.

You know, even a few millivolts. A difference can be the difference between night shutting the thing off or not. So I'll show you that on camera. Maybe maybe it might work this time because I've discharged this one a little bit.

I don't know. let's have a look. So I've put in a bit of oh, there we go. No oh hell-oh night, See, it just shut off.

But there you go. Yeah, we did see like seven and a half amps on there very briefly so I can try that again before the you know we only got a second before it gets to its next detection window. And there we go. Seven, Seven and a half.

Yep and just switches off. but there you go. It does actually charge at, well, seven, Half eight? Yeah, yeah, no near enough. And if I discharge just one battery, then well, it's exactly the same as before.

All of the bypass vets are turned on and all the charge fits are turned off now. I Think it's appropriate at this point that we break out a tool that's incredibly valuable. If you got it, it's this aim TTI Oh, I Proba 5:20 It's a positional current probe and you might have seen this. I've used it just a couple of times in videos, but it's incredibly handy.

What it is is it's basically an isolated probe with a magnetic field measurement coil on the end and can basically give you. allows you to get in there and probe individual traces and look at the current flowing through them. Perfect for an application like this where you got like, you know, substantially high currents. not easy to break into things and we can just put this on the trace here for example and I'll hook it up to our scope.

It's got an oscilloscope output here and we can actually look. They're charging and discharging waveforms through various PCB tracers. so let's give it a go now because of the relative nature of the measurement on this thing. If you want an absolute quantitative measurement ie.

it to be calibrated and accurate in terms of volts / amps output, then you've got to actually calibrate the thing with this built-in that calibrator. There's a little PCB trace down here. I've done this in the previous video, but I might just run over it again. Now, you've got this calibration chart inside here and basically you need to know the trace width you're measuring.

I Think my ones, It's complicated because there's actually that the one with the link installed. so it's a link with a PCB trace underneath and it's like, you know, it's all completely dodgy. Anyway, we'll have a go I think it's about three millimeters up wide. So we're looking at around about the calibrator output of three volts peak-to-peak So let's set that up.

So what we want to do here: Stick this in the calibrator. Whack it on AC here and you'll notice how it's a little bit fiddly. You want to get in the position so it's them so it's the highest amplitude. You basically can't go over pretty much and you'll notice that if I rotate it, it drops in amplitude because well, it's perpendicular to the trace.

So and of course, if we go in the other direction I can show you this as well. If you have DC for a switch it to DC instead of AC, you'll notice that one way is positive and the other way is negative. So you can actually detect current in both directions with this thing. Anyway, we need to set this thing to What? Three Volts peak-to-peak So I adjust the sensitivity here until we're out about the way we're over there.

Let's turn it down. Oh A Silver Sovereign. Alright, Three Volts peak-to-peak There we go. We're ready to go.

Hopefully that'll give us, you know, a roughly an absolute value. But like I said, we don't need an absolute value here. Measuring this thing adjust to get just to see the waveforms is enough. You don't actually need a quantitative measurement, but hey, you know, do that for kicks.

And then when you're mucking around with current probes like this, you can actually go into your channel going to your probes set up here. and instead of the regular volts volts per division, we can change this to amps per division and then the probe itself. It's already actually just happens to already be set up at 1 volts per amp, which is exactly what we set this thing up for. So now our peak to peak value here will actually be in Milliamps instead of that volts.

It's It's just nice at most modern scopes, so you'll be able to set up our current probes like this. It's very handy now. let's actually put our probe on here and see if we're accurate. I I Think it's gonna be pure luck.

if we're actually accurate or not. that's actually I Got it round back. Would you see how it went negative there? So we just spin it around? Not that it matters positive or negative, but there we go. It looks like we've got some ripple in there.

We might be able to trigger on that, but you'll notice that we're at 2 amps per division hopefully and see that 2 amps per division. So 2, 4, 6? Yeah, we're kind of. You know this. 7.

We're kind of sort of not not there. Hang on. What's gone wrong? Something's happened. Don't the batteries actually full? adages, cutoff, go figure.

But we got within a reasonable ballpark there. just over 6 amps or something like that and you'll notice that hey, there we go. That is our current switching off and on. There it is.

You can see it. Bingo. We're capturing exactly what we did before. If we go to 500 milliseconds per division, then we'll actually see that current.

yet. Bang bang bang. There we go. Now, let's see if we can have a look at that ripple.

I've gone into our AC motor. Oh damn it, If we are, we're full again. Not a bloody full battery. And there we go.

That's our AC ripple. You know that we're at ten microseconds per division, about two divisions, around about 50 kilohertz, our switching frequency or there abouts. So that is our D that's our DC the DC converter. So and there we go.

500 milliseconds, You'll see it switch. bang-bang-bang So what? I'm effectively measuring down there that link on the bottom that's actually just in here. It's like it's before this shot. I Can't quite get into the in there with the shunt unless I Get rid of all of these anyway.

it's but still, it's that ground trace that comes out of there so effectively measuring the current through that shunt. And yes, of course, the good thing about having a mixed signal oscilloscope like this digital analog in the same scope is we can actually correlate the analog Channel up here with the all the digital stuff that we saw down here. So we capture it in. Bingo.

Here's the analog. You can see that it switches the charge, switches off BAM Like that when our charge level here actually goes low and switches back on. And then we've got a large amount of ringing there when the DC to DC converter starts back up that constant current source because you can see the currents actually drop into zero. If you remember the schematic, it's not just bypass in the battery which it can do, it's actually switching off the converter because if it was just bypassing the battery, we would still see the constant current flowing through that PCB trace.

And but it wouldn't be flowing through the batteries. But we're not. So it is physically switching off the DC to DC converter, that constant current source, and then switching it back onboard. It takes a little while to recover there.

What does it take? A few? Only a couple of milliseconds here? no worries. and then the charge switches back on. So Bingo! It's nice to be able to correlate things like that. This is where if you've got like a USB logic analyzer for example, then you've got your analog scope trying to correlate the two.

It's just much nicer when you have the one instrument like this. Okay, so what I want to do now is actually turn it into discharge mode. Okay, so let's get there. We go.

We've got our charge mode up there. Okay, so we've got our six amps where two ants per division and let's switch it and see what's flowing through that trace. I Think I've got the right button here. BAM Hello hello Hello! 500 millivolts per division.

Bingo! Look at this. It's gone negative. It's gone negative. You saw it from charge mode going into discharge mode.

The current through that trace is negative. That is like I haven't changed the position of the probe. so it's gone from positive to negative. Its flow in the other direction.

Wow, that's interesting. So like I said, I'm measuring this point here. So when it's charging, current is flowing down through here like this. But when we set to discharge mode currents flowing up.

it's definitely strong flowing through that trace. You saw it. What was it? Six hundred milliamps there. We've got an error.

We know it's measuring about four hundred milliamps on this thing, but there was definitely current flowing back through. So how the hell is that Is it doing that? Wow Is that is this going negative or something? What? And by the way, if you're curious to know how accurate the voltage is on this thing, I'm going to. it's one point, three, seven, one on there and on the display here. Sorry.

I can't show you one point three, two. so in near enough I Think there might be some more error up at eight amps. So let's measure the charge. I'm now charging eight amps Wow Look at that one point, eight, four volts.

Wow That's above the recommended cutout, which is usually one point eight and it's displaying one point five, nine. There we go: one point six. So there's a 200 millivolt discrepancy there. So the differential measurement I'm painting they're not even doing differential measurement is quite poor so that that yeah, that's not good at all.

and that's a bit how you doing. Not happy with that? I'm by the way I was showing this in previous videos, but I'll just say it again. Another trap for young players. Watch this: If I turn this probe, you might be able to see the green lot and green trace.

move there. That's the two ants per division. That is the Earth's magnetic field. Doing that and it's actually worse I didn't didn't compensate for that before.

If I'm now at 500 milliamps per division. oh, look at that way. yeah, it's not terrific, is it right in the middle of nowhere? So you've actually got a trace position control on the unit itself. so you've got a center that down there when you've got it in position and it's actually not too far off the displayed value.

Now that I've actually zeroed that thing, it's 500 milliamps per division there and we get in. You know around about you know that 350 were 400 What? It's actually displaying on the thing, so it's not too far off. So absolute caliphate and bration and you know it's gonna be within. You know we can like 20% or something.

Now what? I'm gonna check now is a trace up the top? I don't know. like the width? I haven't set the width properly I'd have to recalibrate to get absolute I Just want to see if there's anything there. There's anything flowing into this, so if it's like going somehow back up the chain and out here. so there's a trace right on top here for zero.

That and nope nothing. It's not budging. so there's nothing flowing through that trace going back to the DC to DC converter. So I'm still none the wiser where this damn current is coming from or going I think I'm gonna have to disconnect all these clips again because we've done that with.

you know, figured out that the things multiplex and everything have another decent look at the at the traces in there, see if I can see anything. Hmm and don't stupid me if I spent a few more minutes actually reverse engineering this board before I went off half-cocked and did the schematic. Yes, I would have found the discharge path. Here it is.

It's bleeding lis obvious there's actually here. Okay, here's the positive terminal of the lower battery. Here here's the shunt. I was measuring before by the way, that ground shunt and here's the top.

MOSFET So the positive terminal. Okay, it actually there's a trace that goes off under there and it snakes off around there around there around there into Bingo Q25 Here that's got to be a little, that's a little SOT 23 MOSFET And then there's two. Six are two resistors in parallel under that that actually then go back to ground on the other side. Here's that current shunt resistor in there.

and so the other side of that. Bingo. And it wasn't so obvious on these ones here. For example, here's the next one and then the next one.

So there's actually four of these duplicate discharge transistors. discharge MOSFETs and this actually drops down through some veers into a trace and actually ends up under the chip here, actually under the thing. So there's V is under there and it goes on the other side. So you just got to follow these things carefully.

And of course, what does that translate into? Well, here it is positive terminal of the battery and we've got ourselves a Once again, it'll be like an N-channel MOSFET there and 2 6 R2 s in parallel. So 3.1 Ohms, 1.3 volts divided by you know, roughly 1 13.1 Ohms gives us around about that 400 milliamps will see in. Bingo. And then they can just measure the drop across this.

But of course some of you might be saying Dave I Actually saw the current change direction through this current shunt. What the hell's going on? Well, it's easy if you think about it during charge. Ok, it comes down through the through the ladder of MOSFETs like here, through here and then down the battery. So the current is flowing in this direction when it's charging.

Okay, which is what we got and when we discharged, it was flowing in the other direction. How does it do that? Well, of course in the positive terminal of the battery, it's now flowing out here like this. So and of course we're doing conventional current flow. None of this electron current flow rubbish.

Okay, so it go in from the positive through the mosfet down through here and it's going into ground. But there's or, as always, write Kirchoff's current law like there must be a loop there. right? So that current? Where does it go? It goes through the ground plane and then bingo back up through there like that. So that's why the current changes direction now.

I Know that I Said this was going to be a quick video. Well, as always, that was the intention. but you know I ain't got carried away. Got a little bit excited, you know? I went down the rabbit hole and and anyway, we eventually found out what the hell was happening here.

Yes, these are all. these are multiplexed and we've We found the discharge path in the thing and we realized that the voltage sensing on there wasn't that great. You know it's It's not terrific, so it's it's really is. It's kind of like a clever design like I Really like the way that they've done the switching in this thing.

It really is quite clever, but you know in the end it's not a great, you know, accurate implementation in terms of our charging and voltage detection and that sort of thing. So yeah, it's a bit rough and ready, but hey, you know it's built down to a cost and that's what you get. But anyway I hope you liked that little adventure here. We got to play around with our little like current probe.

This is always fun to play around with. You ever get a chance to get one of these puppies. They're not cheap I think don't quote me but they're like 700 bucks or something. but these are really great.

You know you don't have to break in to the power supply and it's insulated so you can get in into, you know, really high voltage. uh stuff. Get in there like you know, I've already switch mode power supplies and actually probe stuff and get the waveforms. It's absolutely fantastic.

Credibly valuable tool for stuff like that. It would have been really ugly if we had to get in there. and you know, hack in current shunts and meters and things like that, you know, cut the traces and it's just yeah, they're really quite ugly. This is really handy too, and that's a really good example of using it.

We did some good examples of art mixed signal capture there, and things like that, a bit of reverse engineering a circuit tracing it had a bit of all this video so I hope you enjoyed it. If you did, please give it a big thumbs up if you want to comment. Eevblog foreign link down below all that sugar jazz. Catch you next time you.