EEVblog 1461 - The MOSFET Search CHALLENGE

Join Dave in the search for an alternative replacement MOSFET. It might not be as easy as it sounds.
Talk about how to identify components and circuit function, MOSFET parameters, and using google and parametric searches on supplier and manufacturer websites.
Can YOU find a -30V 17A P Channel SO-8 MOSFET WITH ESD protection?
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[@JuanJose-tn8yd]

I found the AO4455 -30V, -17A and the UM4447A -30V, -18.5A in a quick search, but i may be breaking the rule that they are not made in taiwan xD By the way, i just search for 30V p-channel mosfet esd protect and look in the imagen search.

[@EEVblog]

You win The Internet!

[@brianhginc.2140]

WARNING: The AO4455 with the gate at -4.5v has a poor ON resistance, it needs -10v before the ON resistance gets really good. The original uses a logic level mosfet like AO4447A & your UM4447A or the normal Fairchild FDS7779Z which is available everywhere, even stock at Digikey/Mouser/Arrow.

[@rkan2]

You should also try yandex reverse image search, it is surprisingly good with very obscure objects... Much, much better than Google's which is rather generic.

[@keithking1985]

your comment brought out some nice tips out of the other guys who answered in there. SO THANK YOU.. I GUESS : )...

[@thekaiser4333]

1 minute on mouser, 4th match: Diodes Incorporated DMP3004SSS However, how exactly is this double zehner?diode protection intended to work? Why would anyone connect an exposed battery terminal or just a battery directly to the gate of a mosfet?! Is that a new thing among engineers nowadays?!

[@gordonwelcher9598]

When high dissipation is required the heat is removed by soldering the multiple leads to a copper plane. The power dissipation is usually specified with heat sinking of various thermal resistances or areas of copper planes. It is important to check the footnotes for this. One of these datasheets specifies a 1 inch pad. The thermal resistances of the junction to leads and ambient are also specified in this way. There are usually graphs or drawings of the performance of the different heat sinking techniques and or sizes. This can be on a separate application note. Sometimes not all of this data is supplied but a careful study can verify the design. Other types of device in this package might require this amount of care in heat sinking. For this application all this thinking is probably not necessary. It was easier when we just attached a heat sink to a TO-220.

[@RobertLeyland]

When searching for specific mosfets I noticed that the ESD protected ones have a Vgs rating that is +-8V or similar, which is the TVS diode rating. That might be an easier way to search for them.

[@warlockd]

I suspect the marketing department for those mosfets said the same thing:P

[@claudiusdan6165]

Hello Dave, Regarding ESD please note that ALL MOS devices have some form of ESD protection. More over, ALL MOS gates are ESD protected. In 40+ years of practicing electronics I encountered only once MOS transistors without ESD protection for gate terminal. So stating for some transistor that are ESD protected is misleading. If you look at the data sheet, the so called ESD MOS transistors are stated to resists to 8kV HBM stress. HBM stands for Human Body Model and is only one of the ESD resiliency test used in semiconductor industry. Regular device are designed and checked to be compliant at least to 2kV HBM stress test. In recent years the ESD requirement was updated to 4kV HBM. Devices stated as ESD are the ones able to sustain an 8kV HBM stress. As a former MOS IC designer I had more issues with other ESD models as “Machine model (MM)” and mostly with “Charged device model (CDM)” that imply higher stress than HBM. The replacement you performed is OK provided you take care when replacing the batteries. Thanks for the very informative post!

[@RexxSchneider]

All of the earliest MOSFETs that I came across were for RF use and had 4 terminals, usually in a TO-18 can. None of them had ESD protection and I lost a couple until I figured out that I needed to wrap thin wire around all of the four legs before handling, only removing the wire after the MOSFET was in circuit.

[@claudiusdan6165]

@@RexxSchneider I first met MOS devices in the early ‘80 and back then all of them were ESD protected. I also learned about ESD in the university… The only MOS devices without gate ESD protection I know were used in the ultrasonic remote control receiver of a Grundig Color TV dating from the early ‘70. The gate capacitance was used to store the control voltage and was accessed via a neon lamp!

[@claudiusdan6165]

@@RexxSchneider The tv was a Grundig Color 8010 UE.TD. BTW, I read about MOS devices with a chastity wire but never used one…

[@woosix7735]

Pls make jellybean MOSFET , JFET and BJT. Video, it would be very useful

[@MomirPeh]

I think that the ESD protected MOSFET has been chosen by the manufacturer because it's used for switching the batteries and their contacts are exposed outside of the casing, thus can get a direct ES discharge from your fingers. :)

[@dilucide]

@9:50 Btw., if you really only want PDF files in your search, use filetype:pdf in your search query

[@jj74qformerlyjailbreak3]

Thanks. It would be nice if an offline database could be scrubbed then created for DataSheets. At least every Ic and part I’ve looked up with I have a database for. It would definitely be a nice to have. I’m sure there’s something in the Wild already doing this.

[@Dedubya-]

Thanks, I was trying to ID a Sinopower 4307 and this really helped

[@digihz_data]

Super information from you Dave.

[@Mtaalas]

Many people don't realize how important this part of the job really is. Good video about important topic for anyone wanting to become a professional :)

[@noahmehlhausen1712]

Especially if you care about the switching losses in inductive load situations. The distributers never list the reverse recovery charge or the Crss >:(

[@adipuiu5603]

At a former workplace I was accused of being to lazy because I wasted a lot of time with searching obscure part equivalents for important clients who regularly bought in bulk supplies.

[@fiddlerJohn]

Good info. Great fun. Thanks Dave.

[@KeritechElectronics]

As always, I hope I learned something. Have a great day :) "MooseFETs"... They have to be made in Canada!

[@johncoops6897]

There is a MooseFET test for Scandinavian motor vehicles!

[@Alex-ze7gn]

On Semi FDS6681Z is the closest I could find with the ESD diode. -30V -20A. 3 times the price of that SinoPower 4303 though.

[@EEVblog]

Another winner of The Internet!

[@AJMansfield1]

One search technique I've had some luck with before when trying to find particular features (such as the ESD diode) is to try to "invent" the part number that a manufacturer I've found making similar parts would label the part I want with. For example, if I've found a 12 volt mosfet both with and without the protection diode carrying similar part numbers, and a 30 volt one without the diode, I might try tacking on whatever extra letter they added to the 12 volt mosfet part number to make it the ESD version to my 30 volt mosfet part number, and searching that.

[@douglas2lee929]

Dave, change your cursor to larger, and colored (yellow?). That tiny white dot is nearly invisible.

[@mrlithium69]

Great Video. I'm glad you uploaded this. The salvaged mosfet was my favorite part of the last video. Now we have a side-quest of finding the replacement from a catalog .

[@PaulSpades]

"Well, if it's reliable and rugged, why did it fail in our product?" Ohhh, Dave.

[@Thorsummoner0]

Dave Dave, i have to know. in this case, could we bodge a dedicated esd discharge diode-thingey across the gate and source?

[@Asdayasman]

When given the opportunity, ALWAYS bodge.

[@BHBalast]

Sure, why not.

[@InssiAjaton]

I have used Central Semiconductor parts for years as one of my alternatives.

[@UpLateGeek]

Dave: Don't click on the ad, it's not the one you want. Also Dave: Clicks on ad without looking whether it matches the part number.

[@Thorsummoner0]

"you don't pay me to copy and paste from the internet, you pay me to know what NOT to copy and paste from the internet"

[@NICK-uy3nl]

Solder 2 external zener diods between Gate and Source and call it good, after all, you are only repairing one unit

[@voyman]

FDS6681Z - bit lower Rdson but other specs match

[@MrTurboturbine]

I accidentally blew up my TS80 soldering iron because I normally power it from my benchtop psu, but I gave it far too many volts which caused the P channel mosfet to go dead short. I happen to have an automotive style LED module that uses a P channel mosfet as input polarity protection. The specs seemed close enough so I used some hot air to swap the chip on the TS80 board, put it back together and I is working perfectly if not better because of lower drain source resistance... That's my mosfet story.

[@dieSpinnt]

For 5V Devices: Use a fixed 5V Power Supply. For 12V Devices: Use a fixed 12V Power Supply. For anything Under Test: Use also current limiting. That is my murder prevention story ... :)

[@MrTurboturbine]

@@dieSpinnt yes that's very true, but I always like to "crank it right up!".

[@mrlithium69]

@51:37 you accidentally searched for S08 with a zero instead of SO8 with a letter o. watch out you dont get sloppy after 45 minutes of searches, or you'll never find it :)

[@EEVblog]

Oops

[@DanBowkley]

30-odd amps in an SO-8 package...yeah I'm going to refer you over to that slow mo guys video with the capacitors. ADHD moment: it's a bit esoteric but a collab video with you and the slow mo guys blowing up a whole bunch of random electronic components would be really amusing. My first *ahem* experiment when I was a wee laddie involved a red LED and a 9v battery and no series resistor...I had no idea they could go purple like that! Anyways I think that'd be pretty neat at 80kfps.

[@lbicknell]

It’s crazy to me that the markings on the chip aren’t searchable on Digikey or Mouser. It’s also crazy there isn’t an open source project that’s a database of all of these markings, photos, etc. given how well indexed other information about components is, the surface markings are a glaring omission.

[@emmettturner9452]

I have reason to believe there is a database of some kind and that DigiKey is using it to sell ads on search results for parts they don’t have. For example, search HSW1699-01-010, which is a HOSIDEN switch used in the Sega Genesis/Mega Drive and Sega Master System. You will get DigiKey ads for slide switches even though they don’t have it and don’t even seem to carry HOSIDEN switches. HOSIDEN was once synonymous with S-Video connectors, not switches, so DigiKey definitely recognizes it as a switch even though I can’t find a source (part number comes from a service manual). Indeed, S-Video miniDIN connectors were often called “Hosiden connectors.”

[@bobert4522]

There’s octopart?

[@emmettturner9452]

@@bobert4522 Octopart links me to a completely different HOSIDEN part that isn’t even a switch, so that doesn’t seem to be where DigiKey is getting their info.

[@dieSpinnt]

@@emmettturner9452 That can also mean that Octopart isn't interested into your Cookie-Internet-Life or simply is ignorant about your manufacturer/product number/code "HSW1699-01-010" ... which seems important to you, but if I am honest to you: not me ... and I am not a part number search engine, but a human, like you:P BTW: The correct answer is: WE DON'T KNOW! Ask them?:)

[@dieSpinnt]

alltransistors (preventing KZbin censorship with a point you have to insert, here, sorry) and com(which is a web address) -> SMD CODE / and similar search sites. Oh and that simply can't be accurate or complete. As an example, try to map the millions of different SOT-23 parts with a 3 or 4 char/digit code plus manufacturer symbol ... :o)

[@wthornton7346]

Invaluable. This is the sort of detail that you only learn by weeks of study or sitting with someone who has been there, done that. Thanks.

[@power-max]

That Sino Power logo looks an awful lot like the old National Semiconductor logo!! 🧐🧐🧐

[@TheChemicalWorkshop]

i have idea for a series: take a random thing (working) - replace a random component with a similar one (bonus if you make bodge wires, incorrect packages and other weird stuff) - check if it's working - repeat

[@tollertup]

repeat until you have swapped all parts and can assemble a copy

[@TheChemicalWorkshop]

@@tollertup yeah, lmao you could replace a lot of parts... i wanna see him go mad, replace some weird chinese timers with a attiny and bodge it in (or worse)

[@DHealey]

What is the reason for the component having 8 pins when it only needs 3?

[@jimjjewett]

Possible reasons include handling more amps, multiplexing from multiple distinct inputs that you don't want directly electrically connected, fitting the 8-pin package for legacy reasons.

[@rene0]

Unfortunately i don't know of any crowd-sourced component databases. Several commercial entities offer them. Would need someone with a follower base to set such up (hint hint).

[@denisohbrien]

small SMD markings are a nightmare, I do automotive component repair, my go-to is to just buy a donor and salvage the bits when they are obviously obscure. or make an educated guess

[@gkdresden]

It seems that you have dumpsters in Australia, which are in fact gold mines. 😮

[@djashley2002]

If you fail to identify the MOSFET is it a case of Q-Anon?😉

[@peterh5165]

Boo Hiss!

[@fwzorren]

I'm glad it's not just me. every time I try to find a replacement component, it seems like that particular part is an obscure, one off. my question is, do you think the light design actually specified that part, or was the MOSFET specification something like "whatever you have laying around above 10 amps and 20 volts"

[@EEVblog]

Could be based on previous design. Parts re-use from other products is a big thing.

[@mc_cpu]

The moral is don't design in weird parts on to your boards unless you really have to.

[@jorgealzate4124]

Perhaps the two MOSFET are in a bidirectional switch configuration and because the ESD protection is already in one gate it becomes redundant at the other gate, so this arrangement maybe saves a few cents on the bill of materials.

[@DanBowkley]

Odd ball "not quite an EE yet" question: I've seen plenty of good reasons to use a MOSFET in lieu of a BJT, but are there any good reasons to go with a BJT over a MOSFET? FETs just look to me like a vastly better option no matter what the criteria, so since BJTs are still being made I must be missing something.

[@transfunktionator]

BJTs can be driven with rather low voltage (0.7V), which does not vary very much. Big FETs need much higher voltage. With matched BJT pairs you can build neat things like current mirrors etc. Threshold voltage of MOSFETs varys quite a bit from part to part. There are certainly many more reasons to use BJTs in certain applications.

[@wwsoft]

Of the dozens of parameters that a transistor has BJTs can be better on certain characteristic like leakage current, robustness to ESD, or switching time.

[@ssl3546]

In the intro to circuits class at MIT they don't even talk about BJTs, they introduce FETs and as far as the students of that class know it's the only kind of transistor that exists.

[@Basic.Electronics319]

In some high power apps, BJT holds an edge over silicon MOSFET. The biggest example I can think of is IGBT, which has MOSFET interface with BJT-like output. This thing is used very frequently in solar or power projects. Not until the last few years that the options become expanded, where we can think about SiC or GaN FET. Then you also have classical works like class AB amplifier. I use them whenever I need a cheap and fast way to drive a speaker. It works extremely well.

[@ekbp3zpe760]

BJTs have much higher transconductance so are much better performers when designing amplifiers. They have lower noise as well, so better for those applications (JFETs are better than BJTs in this category though). BJTs generally have tighter specs; FETs oftentimes have large ranges for important parameters (eg most FETs don't even provide a Vth value like you would expect in school). The list goes on. They all have their place and uses.

[@bobert4522]

Couldn't you make a design change with unpopulated pads for external ESD protection as a backup? I guess if you were sourcing possible alternatives you would in the design stage anyways.

[@shazam6274]

Why, oh Why, would they choose THAT part for an 8 Volt Battery switch? Simple: they found a vendor that had many surplus reels of them and got them for < $0.10 each!

[@danielnelson1983]

How would you have been able to do a search for mosfets before the internet days?

[@keithking1985]

could you the 2 diodes between the gate & source like i the diagram of the inside of the MOSFET (or were they 2 zener diodes in there?? anybody please??

[@andrewneilson492]

it would be really cool to see a deep drive into MOSFET data sheets :), maybe with set parameters on an example application so we dont end up in the weeds :)

[@PaulSteMarie]

Along with translating the datasheet parameters to a SPICE model.

[@vega1287]

i still remember a multimeter i took apart where all the part numbers were printed next to it on the pcb. but the multimeter was so crappy that the trace burnt through before the fuse blew, so i never fixed it

[@alexv3780]

When I search for a datasheet I use partnumber, company if I recognise it or part type and datasheet at the end. Some times the "Images for..." option is very helpful, in this case I tried "4303 mosfet datasheet" and it was the 2nd result in "Images for...". If the partnumber is very common you can use the exclude "-" before a keyword you don't want for better filtering. For the equlivant part I found FDS6681Z & SI4491EDY on Mouser using a wider search on max current

[@johncoops6897]

Search for "*4303 Mosfet Datasheet" - the asterix allows for any characters, so will include prefixes like SN, PT, etc

[@todirbg]

Hi Dave, I found si4491edy-t1-ge3 SO8 available at farnell -30V, - 17.3A, 0.0065 at VGS = - 10 V, 4000V ESD Protection.

[@galileo_rs]

Just go to lcsc and search for the part number, quite a time saver.

[@emmettturner9452]

Regarding 32:00 - When looking for a repair replacement why wouldn’t you look for “Discontinued” and “Last Time Buys?” For the repair industry there’s a chance that what you want is only available that way… which is increasingly more likely the older the device is. You only care about “active” when selecting components for a new design.

[@EEVblog]

This video isn't about the repair, it's about design.

[@emmettturner9452]

@@EEVblog Sorry. I thought it was an exercise for finding a replacement part with the same specs.

[@pnjunction5689]

Epic video! Next time try finding a low Iq LDO that is in actually in stock ;-)

[@jovangrbic97]

Ask and you shall receive, I spec'd these (5V) out recently on Mouser after a long distillation of parts: AP2204 and MCP1792, something like 55V in and 100~250mA current, enough for powering smaller logic...

[@ChrisPavey85]

Hi Dave. If you put filetype:pdf in your Google search you will always get a pdf. It's very useful.

[@EEVblog]

9 extra characters to type, I'm lazy

[@der.Schtefan]

Literally the first result you got at the start, not the second one you clicked, was the SM4303PSK, it even said "marking on chip 4303". Check 09:32. Not sure I understand the tangent you went on afterwards.

[@felixcosty]

The tangent he was going on, is to find a similar part made by a different company. The part that broke was sinopower, and he wanted to know if anyone else made a part that would work, if you could not get a sinopower.

[@jimsmindonline]

This has to be the most frustrating thing as a beginner in electronics. The datasheet search can go on forever sometimes.

[@Thorsummoner0]

more frustrating than every single dead farty-electronic-gizmo having nothing more inside than one big micro? or sometimes several i guess

[@McTroyd]

While I agree the light manufacturer should have picked one or the other FET, were the gates shorted together? Only need one to have protection in that case, I suppose. Though it's interesting the one with protection was the one that failed. 🤷‍♂️👍️

[@Elfnetdesigns]

I found a pile of Digital TV to Analog converters (CORE Innovations, 23 to be exact with a few remotes) a few days ago in the trash enclosure at the place I live, all were dead. Power circuits were the issue ranging from R Kelly'ed capacitors to bad transformers. Anyways the output 5 volts. So my fix for the ones with bad transformers was to literally cut the PUS circuit free from the main PCB via the separation valleys. Then was to gut out old phone 5 volt 1 amp chargers(solder the mains leads on and remove the USB port and solder wires from the power pads where the USB port was on the charger PCB to the filter cap on the converters main PCB and install that PUS in the converter wrapped in caption tape, secure with some hot snot and BAM they all work now.

[@NurdRage777]

This is why I don't throw doner boards away.

[@peteb2]

Awesome Dave. This same dang part has given me sooo much damn grief obtaining the identical (because a substitute is not working)! I even launched a help me on indentify this MOSFET the EEV Forum & it was soon "ideed" & found them via ebay but no mail is being sent from the USA to New Zealand has me putting the light back on the waiting shelf for parts now gathering dust.

[@liveen]

dude, you searched for SINGLE BJTs and then tried to filter by those with more pins, which usually feature arrays etc. what the actual fuck. You also searched IN the signle bjt category, for BJT, which removed a ton of results. You also seemed to forget theres other categories as well. with your parameters searched, and ignoring other SMD packages that would still work in the same board, theres 31 in the matrix category, 26 in the RF category, 3 in the pre-whatever category (not obsolete ones), and 62 in the category for buffers, drivers, transceivers, receivers. dude... No offense, seriously, I look up to you, but how dont you know how to search for components? So yeah, you DO get BJTs in SO-8 packages, but they, same as the mosfets, arent just 1 single transistor with an obscene amount of pins, whats the point in that... Also, in the future, just use alltransistors, you can find the IC in 3 seconds. The second line on the package is LOT number btw, not date code.

[@chenli9734]

If you find components on category companys website, the "-" in parameter columns is totally a nightmare.

[@aishwaryasai9746]

Hope you are doing well. I have a doubt regarding my design of the amplification circuit with an op-amp to amplify the voltage. I have a few doubts regarding the op-amp designing circuits. QUESTION: I need a bipolar output of +/-15V using an op-amp where the input of the non-inverting op-amp is a sinusoidal signal with amplitude of 3.3V from a microcontroller with frequency=40kHz from a DAC unit. But the problem is when I am simulating its outputting the same voltage though I have chosen R2 and R1 resistor. Can you please help me with this issue. Thank you

[@keithking1985]

I HAVE TO ASK DAVE... HOW MUCH EXTRA BUCKS DO YOU PULL IN FROM FIXING DUMPSTER FIND'S AROUND YOUR WORK PLACE????? COZ SOME OF THE STUFF LIKE THAT ONE PIECE WORTH OVER $300,000 WAS JUST CRAZY(THE SPECIALITY SCOPE WITH JUST A LOOSE POWER CABLE.) !!!!WOW!!!! MAN!. SO YOU MUST MAKE A NICE EARNER FROM THOSE SKIP'S ALONE...???

[@tounho]

Could Q also mean vacuum tube? /s

[@thekaiser4333]

1 minute on mouser, 4th match: Diodes Incorporated DMP3004SSS However, how exactly is this double zehner?diode protection intended to work? Why would anyone connect an exposed battery terminal or just a battery directly to the gate of a mosfet?! Is that a new thing among engineers nowadays?!

[@megejaslt]

From my experience selecting right mosfet is not so difficult. Much more difficult is to find right IC. In my case there was needed some SO8 dual rail to rail input, rail to rail output operational amplifier. Max supply voltage not less 36V There is a lot of devices with rail to rail input or rail to rail output only or 5V supply. Originally there was LT1490 and I did not get it in EU for several month... Even if supplier show "in stock" actually none has it.

[@daic7274]

Why am I subjecting myself to such torture during my little bit of rest time..I do enough of this as part of my work. Hunting datasheets for components that have been obsolete for 30yrs before trying to find a replacement can be interesting. I often repair old industrial equipment. I'm sure some information is only available on paper, in a box, in storage at some old retired grey-beard's house somewhere on the planet... Anyone know any technicians that used to work for Gould instruments during the late 80's - early 90's, in the data acquisition section, dealing with thermal array recorders? Info on the TA11 is practically non existent..even in the archives.

[@johncoops6897]

The "VBsemi APM4303" that Dave is rambling about at 20:00 is *NOT* an alternative, because it doesn't have the ESD diodes like the original. He did add an overlay, but it was only on-screen for a few seconds.

[@CaptainDangeax]

Great advice. I will try to fix a force feedback logitech wheel for a friend of mine

[@PsiQ]

Grundfos wants their logo back.. The archimedes water screw / wheel. The ESD is propably there because grabby hands can poke at the battery contacts while charged up.

[@simonilett998]

Looks like you're S.O.L on options for the equivalent S.O.P8 for your L.E.D🤣👍🇦🇺

[@diansong1394]

in retrospect, initial search should make a big deal about image-searching their logo on the ICs 😆

[@kjur18]

17:22 that russian stuff is correct, you will will get this mosfet datasheet on this link, just look at text below link: "Reliable and Rugged"...

[@Rx7man]

I guess if you can't find the exact one, you could bodge some ESD protection onto the board?

[@Asdayasman]

It seems like a dead giveaway that the logo matches. Is there some way to crudely draw or describe the features in a logo you find on a chip, and be presented with a screen full of candidates, which, when clicked, take you to the manufacturer's website?

[@mattymerr701]

Man, digikeys search is so damn dire. And their metadata filters are also not very well curated and missing either a lot of info, or have a bunch of stuff combined making it next to useless for some categories.

[@DavidMarvin]

When YT got rid of the red bar on the recommended videos to show that you watched it I began liking/disliking to know that I watched a video. As soon as I opened this one I clicked on like on the video and paused it.

[@RexxSchneider]

So, as the SM4303PSK was well over-specified, it really is baffling why it failed, right?

[@AvgDan]

53:20 you searched for the right thing but clicked the wrong result. Correct part does have ESD protection.

[@themanyone]

In my (more-)ignorant years, I actually replaced a S08 pkg mosfet in a laptop like that one with one of those big TO-3 pkg that came up in searches. Bodged it in. And it worked fine. Apparently you're right; generic power supply components are not too critical. It was cheap, too.

[@johnsonlam]

Thank you Dave, that's exactly I want to know, very useful.

[@JohnAudioTech]

DigiKey is moving to a marketplace format using Rochester as a source. Quite a few parts are only available through Rochester and you might have to pay extra shipping if your order contains parts from both.

[@andymouse]

Blimey, shipping is already a killer.

[@DavidLindes]

Look out, Limor... "The Great Search" has competition, now! ;)

[@vega1287]

reminds me of the time i had to search for a replacement for a scew terminal and i found it but then at noon the manufacturers website went down

[@stevenbliss989]

I hate the way the 220uF caps are not properly soldered! ...yes I am very anal!

[@stewartthompson72]

The Jameco Electronics Catalogs used to have a really good list of all the manufacturers logos that I found really useful, but I can't find anything equivalent on their web site. Great explanation and example Dave.

[@exxosuk]

I spent 2 years looking at all the specs and trying various mosfets for digital audio amplifiers - my conclusion is - meh . lol

[@petersage5157]

This reminds me of Doug's Secret Squirrel jFET with the built-in gate shunt diodes. What kind of bean counter would specify such an obscure component when you could just add the clamping Zener diodes externally? The mind boggles. (EDIT: Even not knowing much about such protection components, a quick jazz-hands tells me that such built-in ESD protection is a TVS diode, and these are commonly available as discrete components, so...again, why the funtruck?) Is there a Top 5 jellybean MOSFET video in the near future? That would probably be helpful to a lot of your viewers. As far as I can tell, and as a former valve enthusiast, I've given this a lot of thought and devoted many hours to searching for an answer to this question, transistors got stuck with Q for reference designators because they were latecomers to the party; they got seated at the slush table because they didn't RSVP. T was already taken; V would have been the next logical choice because they function as electronic valves, but even when transistors were shiny and new we had a fetish for only allowing vacuum state valves to be called that. Had I been at the table back in the day, I would have advocated for V, but really, "that which we call a rose," and there's too much historical inertia to change it now.

[@gino.avanzini]

I think the image at 39:50 shows that all MOSFETs from Vishay's TrenchFET gen III or IV manufacturing processes have 8kV ESD protection. So Si4425FDY might be a good fit (Vds=-30V; Id=18.3A; Rdson=9.5mR)

[@KGE64]

Anpec makes a similar P-channel mosfet called the APM4303K but the datasheet looks frigthingly similar to the SinoPower but lacks the extra gate protection.

[@stamasd8500]

I've been through this kind of wild goose chase many times, usually ends well but sometimes the parts are just impossible to identify. Especially if they're older parts from 10-15 years ago which are now obsolete, and the obscure manufacturers don't even list those obsolete parts anymore, or have the datasheets. Also in your analysis around 3:50 you miss one other possibility, that the part could have been an IGBT. You could have elaborated there that while an IGBT is possible, it is unlikely because one would likely not use an IGBT for a 8-12V application since those devices have clear advantages over MOSFETs at higher voltages only.

[@Mrbobinge]

45 years ago the V-mosfet slowly replaced elec-mec relays, but it only handled uni-directional power switching. I found that connecting two of 'em back-to-back made a bidirectional switch to truly imitate relay contacts. Took the idea to Siliconix a Vmos maker. They turned it down.

[@OffGridAussiePrepper]

Yep dave u have the power and the know how to find what u need, but wait I still cant find the schotky diodes to repair solar panels.

[@TeslaTales59]

nice repair sir. Let's get some more dumpster diving and teardowns eh?

[@joeyjustin6895]

Good video.

[@markdjdeenix6846]

Thanks this series is very interesting and clever use of the fet from the laptop .but the replacement doesn’t have the E.S.D. Protection? So will you fit the right fet in the future? This was really nice detective work and a step-by-step explanation of finding the data sheet for the faulty part It would be good if there was a place/page with all the manufacturers brand logos it would help find a obscure part

[@MrSummerbreeze01]

Very good video. Key statement, "over specified" confirming what I have found over the years. Always suspect FETs and drivers in soic packages.

[@NeverTalkToCops1]

Breaking! TSMC captured by...

[@fredflickinger643]

ESD MOSFETs sufficiently thrashed. Good illumination of the challenges in finding an identical snowflake!

[@kdog290]

You were close! It was a link at the bottom of the infineon data sheet, BSO080P03NS3E G which has esd protection and fits the spec

[@DavidMarvin]

N-Channel, not negative. P-Channel, positively negative.

[@PaulSteMarie]

Galco is very familiar for industrial automation stuff components. I thought they were a distributor, not a manufacturer, but still a very familiar name. FWIW, Rohm is a lot closer to the bad things happening than Taiwan is.

[@thomasdzubin]

"war in Taiwan" - aaaaahhhh! what does Dave know that we don't???!?!?