It's usually a DC - DC IC that is crucial to the device even powering up at all. And turns out there is no equivalent and the pinout is all over the place.
I would also guess that you also have to occasionally suss out a real-world part number from the manufacture's PN. HP is (was) really good at obfuscating parts. Cheers,
@@EngineeringVignettes - there are some HP cross reference lists floating around, needless to say I try to get as much information as I can for my files.
Same here, component obsolete 30-40yrs ago...no diagrams and any datasheets have long been removed from servers and any paper copies available belong to an old or dead person. Hunting the internet archive is often handy though.
The PFC MOSFET usually fails because of a failed main filter capacitor in my experience, the PFC coil then dumps all the energy into the MOSFET and it releases the magic smoke. It used to be that the main filter cap had an easy life but now with PFC it basically is in a high frequency switching environment.
With 240V input, it's often possible to just remove the PFC MOSFET and see if everything else works to see if it's worth fixing or not. If you're not billed for power factor, you can even just add extra capacitance to make that the permanent fix.
You are so right, I have no clue how amazon got this big with a search like that. Looking for "electric toothbrush" now order by prices Amazon: "Alright here have a Car Tire"
@@Schwuuuuup I searched for "Acme oil filter, p/n 123" and up comes oil filters from other manufacturers, and Acme filters of all other part numbers they stock. It's practically useless.
Electronics components catalog is usually maintained by single party with strict rules. Sale marketplaces like Amazon offload product info, tags, catalog categories to individual sellers who are making a competition of abusing that system. This can not work even in theory.
RS search has some quirks that you have to get used to. Also you might see up the top in the "breadcrumbs" that the last item is the search term, but I often find that I need to click back to the previous level otherwise some parts can be excluded from the search results.
There's an option on RS that's "search by MPN (Manuf. part num?) and when checking that, 18N50 works. Also I saw on the top of the parametric search they had a 'from' and 'to' that you could probably use for ranges. Yet again, another great video showing how to figure out what's a good replacement part. I like this, as it helps me start understanding what are the most important component values to use.... Edit: I see you got there at the end... guess I should have waited haha.
This is the most informative vid that Dave has done, thanks, Dave. I have a terrible time using these searches, always with no or wrong results. If Google doesn't find it, I quit looking.
The hard part is finding replacement switches. In addition to the usual ampacity, #throws, #poles, switch style, etc. you gotta get the right pin pitch and row pitch, and it seems that Mouser and DigiKey don't even offer those items in their parametric search.
I wish I could get next day delivery, it takes two weeks to get anything, a week if they have them locally! Sometimes it takes element 14/RS a few days to even process the order ! Arrow and digikey are much faster, same day processing, maybe a week to arrive.
First one on the list could also be a replacement, I think. Specs look ok, and package is right. Dave tends to miss things like that on camera... But hey, we still get his point :)
@ I've reported some serious bugs on their website where you could buy things for the wrong price - I even sent screen grabs on how it happens and detailed the steps to do it - I never got a response which was really disappointing. One other thing DigiKey does that also drives me nuts is tariffs. Some of them are quite large amounts. When I see that in my cart I remove the item and buy it from Mouser - I saved $100 doing just that on item. That said I do like using them and really appreciate having Mouser and others as alternatives. DigiKey's search is way better than anyone else's though. IMHO
In one of my past projects, I developed a system (for the company) that checks new and existing customers in the consolidated sanctions list. Right now, you are not on the sanctions list for US. It probably was a mistake if you were ever in the list...
Yup and they stopped selling electronic components long before they went too. 2008 is the last dick smith catalogue I have so that's probably when they decided to become a consumer electronics shop only
The Dick Smith brand still exists, but as an online-only consumer electronics store owned by Kogan. Jaycar (in Aus/NZ) is still equivalent to what Dick Smith used to be, which is nice, but their prices lean towards the high side and sometimes can be 10x that of RS or Farnell for things like microcontrollers. They do however have pretty good prices on switches, plugs, potentiometers etc. Surplustronics here in NZ also has pretty good deals on components and tools, although their parts selection is smaller than Jaycar.
Ahh yeah can I have an FDA 18N50... I'm sorry Dave, but I'm afraid that I can't allow you to have that! Parts sourcing odyssey 2021! These are the videos that make this channel what it is, excellent video!
yeah it wasn't just rs that had the 18n50. The element14 site had an 18n50 on the bottom of the page you were looking at for next day shipping. although it was a to-3PN package
Wouldn't you want to also check the gate to source threshold voltage (Vgs)? It probably isn't applicable in this parts use case, but there are also so called logic level MOSFETs with lower than usual Vgs.
Logic-level capability is great when slow consistent latching at high amperage is the task, but for pfc-duty it’s just switching off stray reflections at high frequencies.
This is why I hold onto different array of boards to scavenge parts. Here in Canada, I can't find anything for some specialty parts and have to order through eBay which will takes weeks
I actually used winsource a couple of times to buy parts that are no longer available on the market. Surprisingly its fast and they deliver the real deal.
I'm actually considering them for some parts that other distributors don't stock currently, yet winsource seems to have them in the 1000's. Does their site report their actual stock? Is there anything I need to be aware of when dealing with them?
The asterisk that Dave used does not indicate that this is a regular expression, it is a wild card. These search engines do not respond to regular expressions.
This so much resonates with me. Few days ago, I spent entire night searching for a compatible MOSFET, scouring tons of datasheets (the part situation in India is way worse than that in Australia)
RS search engine is horrible, sometimes i cant find the part i just bought. And one time i bought a part and when it came, the correct partnr. was on paper in the box. When i called them they explained that the storage department doesnt have the same system as the online site. Try searching for "Maxvu16". They sell that bloody thing but you have to use google to find it at their site.
I think the "Manufacturer PN" will only handle the case where actually is a manufacturer-dependent prefix followed by an "industry standard" suffix. This is true for the MOSFET that you show, but not for the PIC18F55. That is just a type number for a device, there are no other XXX18F55 parts that are the same thing. So that would be a difference between searching for *18F55 (which should still work) and searching for 18F55 with the MPN mode enabled.
The flaw that annoys me in the RS filter interface is how it live loads (or does something else) in the background and it locks up with a delay after every click. Quite a nuisance to select a range to look through, or just setup multiple filter categories. Only reason why I prefer something like the digikey interface, it is a lot faster to input all the relevant options with in one go, then get the filtered results.
On the RS website, you just need to click the tiny little slide switch next to the search bar that says "MPN" (manufacturers part number). WTF RS ? Why wouldn't that be on by default ?
I agree that clicking "in stock" on Digikey searches is a must. I also click "Active" as well. I did a recent repair (but with a power transistor. Not so much luck on a direct replacement, had to stuff a bigger package into a smaller hole and mount the package on its back. The saving grace is that is has a higher power capacity and so it can cool itself just fine through the front of the package. Bad luck on the long Digikey wait times, I can normally get orders next-day... normally. Lately not-so-much. Cheers,
Higher power capacity often translates to higher source to emitter resistance, which means the big component/load will also generate more heat than its smaller predecessor.
Element 14... For a small job, I got 100 47uH inductors (Bourns) from them and half of them had broken cores. Emailed them several times, but they did not reply. I haven't bought anything from them ever again. Digi-Key is the best at customer service regardless of the size of the purchase. Mouser is OK in general, but I get awfully 0805 looking 0402 parts every now and then. Waiting few more days for the parts I wanted last week is no fun.
Had a manufacturing company find a farnell part in stock last week that I couldn't find with a parametric search. Going to try and retrace my steps and see what went wrong.
Hey Dave, would you please talk a little about the isolators useful for switching to the metal tab version. I was searching myself a while ago and, not being familiar, It was unclear to me which materials were intended for thermal properties and which were for isolation.
There are two separate things you will need. The one that is often overlooked is an insulating shoulder washer that goes between the device and the screw head or any other metal washer being used under the screw head - this insulated the screw itself from the device’s metal back. The shoulder has to fit inside the hole in the device back, and the shoulder washer opening has to have a diameter to allow the screw to pass through. Then there is the flat insulator that goes between the device back and the heat sink, with thermal compound also being put there. The oldest type of these is probably made from mica, and other materials such as silicon rubber have also appeared for this use. Better thermal conductivity implies lower thermal resistance.
What would you look for searching for something that doesn't have an obviously equivalent part number now like a 2SK or 2SB part? Namely in my case, a 2SK2415-Z? As far as I can see the pat number doesn't have any obvious references to parameters or ratings, and I've had a hard time finding a suitable replacement for it.
Find the data sheet, and then input the parameters into the search interfaces. At some point, the data sheet needs to be available to engineers, and has to have the relevant parameters in it, in order for it to end up in a product.
Just find a mosfet that is close and add an external gate protection bipolar diode. Most mosfets do not have these, so to find one built in like this one is much harder, ...so don't try in most cases :)
Greetings Dave, I wonder if your replacement strategy and searching options can find any data on an IR 725p nothing positive turns up in searches in the UK, though the usual data sheet sites of course list it but it is obviously obsolete, and no one has the precise number, any ideas?
Hi, this is such a great video. However when fixing stuff it often happens that components have no proper part number on it. Like only two/three digits. Is there a proven way to properly identify them?
This is spooky, I just went through this exact procedure trying to source a mosfet from digikey on 3 days ago. Had the same problem the search box couldn't pull up the part and had to do parametric search.
What I don't like about the RS website interface is you can't use CTRL or SHIFT to select multiple parameters at once.. which if you have a wide range of parameters the RS website, that's a whole lot of box clicking
@@userPrehistoricman hahah, I had a friend who when playing monopoly called it "Commodity Chest".. once you read or say something wrong once, it's hard to break the habit!
Thanks Dave, some nice information in there ! but ... salvaging this thing which might be in the first SMPS you grab from the dumpster, that's the way to go (IMHO) faster and cheaper also environmentally friendlier ;) (instead of produce new, package new, ship around the world 2 times ) well, let's see how far we come.
Some of them hiss or whine which I’m sure isn’t good around microphonic components, and has to be terribly hard on solder joints which hasn’t become a design consideration for tiny SMC yet but if they’re a problem, hide the sins under a metal van and maybe nobody who cares will notice.
The ‘new’ element14 parametric search is way better than what it used to be however I still use Digi-Key’s to find 99% of my components, however I now try to avoid element14 whenever I can because they keep screwing up my orders and I’m sick of their horrible thermal labels that fade to nothing but, they offer free hazardous shipping so it's hard to replace them. I never knew those sites had search engines that required advanced query syntax, you’d think they’d make it obvious, definitely not just tricking the stupid autocorrect as *18N* finds the MOSFET but 18N doesn’t get corrected and doesn’t find the part but interestingly FDPF without wildcards does find it but the US RS site finds it with just 18N50. Good example why Octopart is great as it finds it everywhere flawlessly with 18N50. Edit: UA-cam bolds things because of asterisks so just imagine they're still there Interested to know if you were extremely desperate could you have just bypassed the PFC circuit on that PCB? Also recently I had to provide a whole bunch of very personal information to Keithley on the demand of the US government before I was allowed to download my firmware updates!
What if you're looking for a mosfet that is something small like an SOD-123 but it doesn't have any markings on it? Is there a good way to test it to figure out what specs it has?
" more betterer..." great job as always Dave. I am used to putting everything in a plastic box and waiting 2 weeks. My repair area is littered with Fischer extra deep component box 1 compartment - with a paper notes on what I was waiting for . Crazy thing is reading my notes 2-3 weeks later when component arrives OR having a promise for 2 week delivery but get it through 5weeks delivery. Complicating that is perhaps being on the "watch list" ( DoD looks at the name and goes hmmm? could be a spy - we are using that in a military application - had that experience when I wanted to purchase a 22GHz microwave part ). As Hawkeye said in MASH; Military Intelligence - oxymoron ) and living in country Victoria. I do like "Free Shipping" .
Anyone else have a problem with RS Components here in Australia with costing tallying? I recently put an order in with them and the final total price for a few fuses came to like $6 and specifically showed free delivery in the order listing and after I had entered delivery address etc. I put the order in and paid with credit card, after a day I noticed they took something like $18 out saying that delivery was $12!!
Did I miss the part where he confirmed the switching speed? And BTW: I would really be willing to watch 28 minutes to find a replacement connector. With electric bikes and scooters it's really hard to find a matching (i.e. opposite gender) or replacement connector. And I've found they don't put up correct pictures.
Almost everything sold has an "unsellable" last item that physically exists, but serves either as a retail floor demo unit (like at Home Depot) or as a warehouse restocking reference unit (to guard against mislabeled parts). Since such units are physical inventory that must be verified, they are always listed as active stock, which is far easier than making a separate category.
Hey Dave! Could you make a video of things/niceties to pick up from mouser/digikey to bump up the order cost to get free shipping? Things to look out for etc.
@@EEVblog cheers for the reply! Yeah I've normally just browsed for tools and such to get it up. Last time it was a fancy arse solder pump. Gotta make a list of things I can add.
@@codersg Plastics are a poor conductor of heat, not an insulator of heat, but it is probably glass-filled plastic and glass is a better heat conductor than the plastic (still poor compared to metals). I believe you can have alumina-filled plastic which would be better still. Diamond would be the best material :)
For parts, I always use Aliexpress. I don't even bother looking at the others anymore. 2€ for 10 pieces Delivered to Belgium. Usually that's about 11 days. Many different shops to choose from, possibility to chat with the seller and ask questions or negotiate. I usually order a bit more for my personal stock. Never been disappointed.
@@gaberboraey5477 I don't look at the sellers, I just search for the part, then buy 5 or 10 pieces of the cheapest seller, sometimes from 2 or 3 sellers, just to increase my chances of getting it quickly. I do admit that I have had some bad experiences on Aliexpress in the past, bad parts or plain right scam, but that's only like 5 out of 1000s of orders so that's just life, and hey, getting scammed for $3-4 is just water under the bridge.
Off-topic question, but does anyone know what happened to the uSupply project? It looked so promising, but I haven't heard anything about it in almost a year.
An interesting feature that I somehow figured out with Digikey is the use of the "pipe" OR operator. If you want to compare two parts in Digikey, copy the first part number Into a search window then add the pipe character | and then add the second part number. The search results will show results for both part numbers. You can then click on the check box for both part numbers and click on the compare button. Here's a video that explains it ua-cam.com/video/-U0WXC1onUY/v-deo.html
I used to work on stratus computer stuff and it was a dig to find some of the i/o memory chips for archaic retro compatibility issues that never stopped anything and had multiple workarounds. A week recreating a glitch on an X.25 card that was never used but would alert if it's lock-step logic went "Blah". I envied my colleague who worked on memory boards - Alpha particles!
Boy do I miss when RS did free shipping on everything... really sped up projects. Now I have to put it on the backburner until i've got enough stuff in my cart to make it worthwhile. Wouldn't be too bad if the stuff jaycar sold wasn't junk
You know, I've never payed attention to MOSFET part numbers and when you pointed out the nome- nom- er - nculture damn naming convention I grabbed my bits and odds box and had a look - and yeah it is fairly consistent. Wow now I've got an idea of some parameters of those buggers at a glance.. But hey Dave i think you should make a video explaining your expressions. Thought of this after i heard "shits and giggles" which i used to hear a lot in QLD but not so in NSW. Like for example what is the origin of "nothing burger" is it a nation wide expression. Anyhow could be fun for...well shits and giggles. Cheers.
Can't make those FETs arbitrarily large though. Bigger and faster FETs have higher gate drive power needs and at some point, incremental gate drive power will be greater than incremental switching and ON loss reductions. Bigger drivers for bigger FETs add quite a bit of cost too.
found it immediately at mouser. I normally take away the prefix to do a search. www.mouser.es/ProductDetail/512-FDPF18N50T www.mouser.es/datasheet/2/308/FDPF18N50T-D-1808312.pdf oh! i saw that you finally got it!...well, mouser has it either...
If I need specific parts for anything's the first address is Google to see, if it is generally available. My second address is eBay. That led me even to a beefier part for the repair of my boiler controller.
All these websites lack of client/user experience.. Searching function is basic and has to be perfect or you loose lots of customers. I don't understand why they still haven't fixed all that..
must be "boomeritis"... I have it too.. but who designs the UI for a lot of the websites these days?? I too find them overly convoluted. Went through a very similar thing a couple of months ago when trying to find a replacement mosfet for one of these fancy new drills with the 3 phase brushless motors in them (that was trash picked too)... eventually caught on to mpn search and asterisk wildcards and found what i needed.
Usually in my case the part is obsolete and needs some kind of sub that works.
It's usually a DC - DC IC that is crucial to the device even powering up at all. And turns out there is no equivalent and the pinout is all over the place.
I would also guess that you also have to occasionally suss out a real-world part number from the manufacture's PN.
HP is (was) really good at obfuscating parts.
Cheers,
@@EngineeringVignettes - there are some HP cross reference lists floating around, needless to say I try to get as much information as I can for my files.
In my case the component has usually vaporised so if I can’t find a schematic I’m screwed anyway 🤣
Same here, component obsolete 30-40yrs ago...no diagrams and any datasheets have long been removed from servers and any paper copies available belong to an old or dead person. Hunting the internet archive is often handy though.
The PFC MOSFET usually fails because of a failed main filter capacitor in my experience, the PFC coil then dumps all the energy into the MOSFET and it releases the magic smoke. It used to be that the main filter cap had an easy life but now with PFC it basically is in a high frequency switching environment.
SPOILER: In this case it snotted the diode too.
usually blows the gate resistor/diode and the current sense resistor in the source as well i find
With 240V input, it's often possible to just remove the PFC MOSFET and see if everything else works to see if it's worth fixing or not. If you're not billed for power factor, you can even just add extra capacitance to make that the permanent fix.
@@EEVblog yet another diode with jumper envy.
Sir u have no idea how much this video have helped me.
Thank you very much.
Love parametric search engines. Wish Amazon had one...
You are so right, I have no clue how amazon got this big with a search like that.
Looking for "electric toothbrush"
now order by prices
Amazon: "Alright here have a Car Tire"
@@Schwuuuuup ya Amazon search seems to be developed back in the last century. It is darn frustrating to use no matter what you are searching for.
Amazon's search might even be worse than Reddit's, and that's quite a feat. No clue how amazon's search is still so unusable.
@@Schwuuuuup I searched for "Acme oil filter, p/n 123" and up comes oil filters from other manufacturers, and Acme filters of all other part numbers they stock. It's practically useless.
Electronics components catalog is usually maintained by single party with strict rules.
Sale marketplaces like Amazon offload product info, tags, catalog categories to individual sellers who are making a competition of abusing that system.
This can not work even in theory.
There's a lot of competition in the MOSFET world. If your part number is wacky it makes it harder for potential customers to find the part they need.
this stuff confused the hell out me when i 1st started learning electronics, so im sure this video is a huge help to loads of people.. : )
RS search has some quirks that you have to get used to.
Also you might see up the top in the "breadcrumbs" that the last item is the search term, but I often find that I need to click back to the previous level otherwise some parts can be excluded from the search results.
This.
There's an option on RS that's "search by MPN (Manuf. part num?) and when checking that, 18N50 works. Also I saw on the top of the parametric search they had a 'from' and 'to' that you could probably use for ranges. Yet again, another great video showing how to figure out what's a good replacement part. I like this, as it helps me start understanding what are the most important component values to use.... Edit: I see you got there at the end... guess I should have waited haha.
This is the most informative vid that Dave has done, thanks, Dave. I have a terrible time using these searches, always with no or wrong results. If Google doesn't find it, I quit looking.
The hard part is finding replacement switches. In addition to the usual ampacity, #throws, #poles, switch style, etc. you gotta get the right pin pitch and row pitch, and it seems that Mouser and DigiKey don't even offer those items in their parametric search.
I wish I could get next day delivery, it takes two weeks to get anything, a week if they have them locally! Sometimes it takes element 14/RS a few days to even process the order ! Arrow and digikey are much faster, same day processing, maybe a week to arrive.
Digikey & Mouser are still about 3-4 days to Sydney. Can add a day depending upon order and delivery timing.
Luckily where I am in Canada I can order parts from Digikey and get them the next day.
This video is just what i needed, thanks Dave! keep up the good work :)
At 17:12 Dave: "We have nothing here" Me: You have a freakin FDA18N50!!!!
First one on the list could also be a replacement, I think. Specs look ok, and package is right.
Dave tends to miss things like that on camera... But hey, we still get his point :)
And they might wonder why they selling near nothing :0
I was shouting "asterisk" for the whole time.
Finally you used it ;)
The hell... I was facepalming the whole video...
I wish DigiKey was next door to my house. They'll never be able to remove me from the premises :)
@ I've reported some serious bugs on their website where you could buy things for the wrong price - I even sent screen grabs on how it happens and detailed the steps to do it - I never got a response which was really disappointing. One other thing DigiKey does that also drives me nuts is tariffs. Some of them are quite large amounts. When I see that in my cart I remove the item and buy it from Mouser - I saved $100 doing just that on item. That said I do like using them and really appreciate having Mouser and others as alternatives. DigiKey's search is way better than anyone else's though. IMHO
In one of my past projects, I developed a system (for the company) that checks new and existing customers in the consolidated sanctions list. Right now, you are not on the sanctions list for US. It probably was a mistake if you were ever in the list...
Besides learning more about selecting components I’m even more happy to learn some great Australian expression like the one at 13:43 😊
I think it would be a great video to go over what all the major specs of transistors and mosfets are and demystify some of the confusion around them.
STP18N55M5 relatively new "super junction" technology now are really cheap and runs much cooler due to less Rds and lower switching charges.
Is Dick Smith still around? Remember looking at catalogs my dad had going back to the 80s.
Long gone mate.
Yup and they stopped selling electronic components long before they went too. 2008 is the last dick smith catalogue I have so that's probably when they decided to become a consumer electronics shop only
Aw dang went way of Radioshack then
@@MM-lv8ib The internet killed them both. Jaycar is about all we have left for basics.
The Dick Smith brand still exists, but as an online-only consumer electronics store owned by Kogan.
Jaycar (in Aus/NZ) is still equivalent to what Dick Smith used to be, which is nice, but their prices lean towards the high side and sometimes can be 10x that of RS or Farnell for things like microcontrollers.
They do however have pretty good prices on switches, plugs, potentiometers etc.
Surplustronics here in NZ also has pretty good deals on components and tools, although their parts selection is smaller than Jaycar.
I remember when Fairchild was a stone's throw from my house, such a long time ago.
A nylon shoulder washer might be better as, the screw can still slip and touch the sides of the metal mounting.....and then the magic smoke gets out.
The partner to RSComponent Allied Electronics has no problem accepting 18n50 and mosfet.
"The bloody bastards their search is buggered!!!" Nice on RS - lol. Dave discovers the wildcard symbol :)
Thanks for making this dave !
Helpful information
Just a note- mosfets with an insulated tab are TO-220F package or isowatt package.
Ahh yeah can I have an FDA 18N50...
I'm sorry Dave, but I'm afraid that I can't allow you to have that!
Parts sourcing odyssey 2021!
These are the videos that make this channel what it is, excellent video!
I remember when (Geezer: "When I was a boy...") the 18N50 was common as clarts. Wasn't that one of Great Scott!'s go-to MOSFETs for a while?
yeah it wasn't just rs that had the 18n50. The element14 site had an 18n50 on the bottom of the page you were looking at for next day shipping. although it was a to-3PN package
Thanks Dave. I think I found the right replacement mosfet.
Wouldn't you want to also check the gate to source threshold voltage (Vgs)? It probably isn't applicable in this parts use case, but there are also so called logic level MOSFETs with lower than usual Vgs.
Logic-level capability is great when slow consistent latching at high amperage is the task, but for pfc-duty it’s just switching off stray reflections at high frequencies.
This is why I hold onto different array of boards to scavenge parts. Here in Canada, I can't find anything for some specialty parts and have to order through eBay which will takes weeks
Can be very handy!
"Avalanche energy in the megajoules..." and that is how Dave accidentally let slip which mosfet drives the z machine lol
I actually used winsource a couple of times to buy parts that are no longer available on the market. Surprisingly its fast and they deliver the real deal.
I'm actually considering them for some parts that other distributors don't stock currently, yet winsource seems to have them in the 1000's.
Does their site report their actual stock? Is there anything I need to be aware of when dealing with them?
I'm sure someone has pointed out that the f is fullpack, the rest you got 18a n ch 500v, fdp is fairchild semi or onsemi now
Great video Dave!! Love these!
Great tip with the asterisk Dave, thank you
Regular expressions for searching and pattern matching were used in the early days of Unix and now show up everywhere.
ok grandpa
ok boomer
@@cesaru3619 if you had an ounce of creativity, you could’ve said “grep-Pa”. But you don’t & so you could-N’T.
@@wphanoo I always wanted to see the graph of age vs how long I could put up with a girlfriend before dumping her just for being too damn-dumb.
The asterisk that Dave used does not indicate that this is a regular expression, it is a wild card. These search engines do not respond to regular expressions.
This so much resonates with me. Few days ago, I spent entire night searching for a compatible MOSFET, scouring tons of datasheets (the part situation in India is way worse than that in Australia)
RS search engine is horrible, sometimes i cant find the part i just bought. And one time i bought a part and when it came, the correct partnr. was on paper in the box. When i called them they explained that the storage department doesnt have the same system as the online site. Try searching for "Maxvu16". They sell that bloody thing but you have to use google to find it at their site.
I think the "Manufacturer PN" will only handle the case where actually is a manufacturer-dependent prefix followed by an "industry standard" suffix.
This is true for the MOSFET that you show, but not for the PIC18F55. That is just a type number for a device, there are no other XXX18F55 parts that are the same thing.
So that would be a difference between searching for *18F55 (which should still work) and searching for 18F55 with the MPN mode enabled.
Thanks dave this sort of vid is worth its weighty in gold for a young (ish) player like me
The flaw that annoys me in the RS filter interface is how it live loads (or does something else) in the background and it locks up with a delay after every click. Quite a nuisance to select a range to look through, or just setup multiple filter categories. Only reason why I prefer something like the digikey interface, it is a lot faster to input all the relevant options with in one go, then get the filtered results.
Arrow is the worst
On the RS website, you just need to click the tiny little slide switch next to the search bar that says "MPN" (manufacturers part number). WTF RS ? Why wouldn't that be on by default ?
Don't overlook Vgs. These are the same, but a 3.3v micro will not be able to drive these.
Nomenclature is the correct word, indeed. :)
Try saying the stupid thing in a hurry...
Thanks for sharing Dave. Super informative (..agree, the RsComponents have very nice Gui. Wish all the other one's could have had this tidy'nes)
"its gonna be completely equivalent"
> Fast forward 3 days to him bricking his TV when subbing in the replacement transistor
I agree that clicking "in stock" on Digikey searches is a must. I also click "Active" as well.
I did a recent repair (but with a power transistor. Not so much luck on a direct replacement, had to stuff a bigger package into a smaller hole and mount the package on its back. The saving grace is that is has a higher power capacity and so it can cool itself just fine through the front of the package.
Bad luck on the long Digikey wait times, I can normally get orders next-day... normally. Lately not-so-much.
Cheers,
Higher power capacity often translates to higher source to emitter resistance, which means the big component/load will also generate more heat than its smaller predecessor.
Element 14... For a small job, I got 100 47uH inductors (Bourns) from them and half of them had broken cores. Emailed them several times, but they did not reply. I haven't bought anything from them ever again. Digi-Key is the best at customer service regardless of the size of the purchase. Mouser is OK in general, but I get awfully 0805 looking 0402 parts every now and then. Waiting few more days for the parts I wanted last week is no fun.
Thanks for your videos. Hello from Russia.
Well hello from Poland now we only need someone from Germany.
@@crusaderanimation6967 German here :D
Hi, not sure if I just missed the part where Rdson values are mentioned. Should Rdson be the same or lower, the lower Rdson is the better?
Thanks!!!
Cool! Any more camping gear reviews?
Haha, Dave on the watch list. Don't worry, there are a lot of us on their watch list.
Had a manufacturing company find a farnell part in stock last week that I couldn't find with a parametric search. Going to try and retrace my steps and see what went wrong.
Hey Dave! Hope you are having a great week so far :)
Hey Dave, would you please talk a little about the isolators useful for switching to the metal tab version. I was searching myself a while ago and, not being familiar, It was unclear to me which materials were intended for thermal properties and which were for isolation.
There are two separate things you will need. The one that is often overlooked is an insulating shoulder washer that goes between the device and the screw head or any other metal washer being used under the screw head - this insulated the screw itself from the device’s metal back. The shoulder has to fit inside the hole in the device back, and the shoulder washer opening has to have a diameter to allow the screw to pass through.
Then there is the flat insulator that goes between the device back and the heat sink, with thermal compound also being put there. The oldest type of these is probably made from mica, and other materials such as silicon rubber have also appeared for this use. Better thermal conductivity implies lower thermal resistance.
What would you look for searching for something that doesn't have an obviously equivalent part number now like a 2SK or 2SB part? Namely in my case, a 2SK2415-Z? As far as I can see the pat number doesn't have any obvious references to parameters or ratings, and I've had a hard time finding a suitable replacement for it.
Find the data sheet, and then input the parameters into the search interfaces. At some point, the data sheet needs to be available to engineers, and has to have the relevant parameters in it, in order for it to end up in a product.
Just find a mosfet that is close and add an external gate protection bipolar diode. Most mosfets do not have these, so to find one built in like this one is much harder, ...so don't try in most cases :)
Greetings Dave, I wonder if your replacement strategy and searching options can find any data on an IR 725p nothing positive turns up in searches in the UK, though the usual data sheet sites of course list it but it is obviously obsolete, and no one has the precise number, any ideas?
Hi, this is such a great video. However when fixing stuff it often happens that components have no proper part number on it. Like only two/three digits. Is there a proven way to properly identify them?
I would search for 18N60, the voltage is crucial here. Any reasonable search engine automatically adds asterisks.
Being in Canada, I only buy from Digi-key. $8 for next day delivery with no headaches.
The rest can suck it, with their ridiculous shipping charges.
This is spooky, I just went through this exact procedure trying to source a mosfet from digikey on 3 days ago. Had the same problem the search box couldn't pull up the part and had to do parametric search.
MOSTFET.. I think you should trademark that name for some next gen Mosfet!
What I don't like about the RS website interface is you can't use CTRL or SHIFT to select multiple parameters at once.. which if you have a wide range of parameters the RS website, that's a whole lot of box clicking
I think I had a lecturer once who couldn't stop saying MOFSET
@@userPrehistoricman hahah, I had a friend who when playing monopoly called it "Commodity Chest".. once you read or say something wrong once, it's hard to break the habit!
Thanks Dave, some nice information in there !
but ... salvaging this thing which might be in the first SMPS you grab from the dumpster, that's the way to go (IMHO) faster and cheaper also environmentally friendlier ;) (instead of produce new, package new, ship around the world 2 times ) well, let's see how far we come.
Does element14 share the catalog with avnet?
17:06 exactly the part you're looking for FDA18N50 (bottom of screen), while you say "no NO". 49 available next day
do mosfets wear or age? how about a scavenged one that's close enough? I've found some really beefy mosfets in switching power supplies
Electromigration is a thing, but unless it's some really old stuff (in which case they probably aren't that beefy) then it'd be fine
Some of them hiss or whine which I’m sure isn’t good around microphonic components, and has to be terribly hard on solder joints which hasn’t become a design consideration for tiny SMC yet but if they’re a problem, hide the sins under a metal van and maybe nobody who cares will notice.
The ‘new’ element14 parametric search is way better than what it used to be however I still use Digi-Key’s to find 99% of my components, however I now try to avoid element14 whenever I can because they keep screwing up my orders and I’m sick of their horrible thermal labels that fade to nothing but, they offer free hazardous shipping so it's hard to replace them.
I never knew those sites had search engines that required advanced query syntax, you’d think they’d make it obvious, definitely not just tricking the stupid autocorrect as *18N* finds the MOSFET but 18N doesn’t get corrected and doesn’t find the part but interestingly FDPF without wildcards does find it but the US RS site finds it with just 18N50. Good example why Octopart is great as it finds it everywhere flawlessly with 18N50. Edit: UA-cam bolds things because of asterisks so just imagine they're still there
Interested to know if you were extremely desperate could you have just bypassed the PFC circuit on that PCB?
Also recently I had to provide a whole bunch of very personal information to Keithley on the demand of the US government before I was allowed to download my firmware updates!
Yes, the thought had crossed my mind to simply bypass it, and I might try that as demo hack maybe.
@@EEVblog Am about to repair the PFC on a Samsung monitor too that sucker uses a KF12N60 have not had time to replace it yet but soon :)
@@EEVblog for RS near the search try ticking the search MPN box ;) since your searching by code anyway
*-*18N*-**
* *-*-*_-18N*-_
What if you're looking for a mosfet that is something small like an SOD-123 but it doesn't have any markings on it? Is there a good way to test it to figure out what specs it has?
I search for components like this nearly every day.
How about the order of the 3 leads: Gate, Drain, Source vs. Source,Gate, Drain, vs Drain, Source, Gate?
Use wildcard search (example: "*18n50") and the parts show up.
Watch the video dude..
" more betterer..." great job as always Dave. I am used to putting everything in a plastic box and waiting 2 weeks. My repair area is littered with Fischer extra deep component box 1 compartment - with a paper notes on what I was waiting for . Crazy thing is reading my notes 2-3 weeks later when component arrives OR having a promise for 2 week delivery but get it through 5weeks delivery. Complicating that is perhaps being on the "watch list" ( DoD looks at the name and goes hmmm? could be a spy - we are using that in a military application - had that experience when I wanted to purchase a 22GHz microwave part ). As Hawkeye said in MASH; Military Intelligence - oxymoron ) and living in country Victoria. I do like "Free Shipping" .
Anyone else have a problem with RS Components here in Australia with costing tallying? I recently put an order in with them and the final total price for a few fuses came to like $6 and specifically showed free delivery in the order listing and after I had entered delivery address etc. I put the order in and paid with credit card, after a day I noticed they took something like $18 out saying that delivery was $12!!
What was the MOSFET used in?
Did I miss the part where he confirmed the switching speed? And BTW: I would really be willing to watch 28 minutes to find a replacement connector. With electric bikes and scooters it's really hard to find a matching (i.e. opposite gender) or replacement connector. And I've found they don't put up correct pictures.
What is with the MOSFET from Vishay Siliconix that is labelled 18N50, but has 17A in the specs?
"1 in stock" yeah, been there, tried that. Whenever/wherever lists "1" instock, usually none.
Almost everything sold has an "unsellable" last item that physically exists, but serves either as a retail floor demo unit (like at Home Depot) or as a warehouse restocking reference unit (to guard against mislabeled parts). Since such units are physical inventory that must be verified, they are always listed as active stock, which is far easier than making a separate category.
Yeah, I wish it was that easy getting a micro controller these days :(
I wonder if the sites that require asterisks are more susceptible to SQL injection.
Glob me this glob me that who’s afraid of the big black hat?
I swear that the search function on RS worked better before they "upgraded" their website a few years ago.
Hey Dave! Could you make a video of things/niceties to pick up from mouser/digikey to bump up the order cost to get free shipping? Things to look out for etc.
Consumables usually. Solder, solder wick, flux etc Test leads and adapters are always handy.
@@EEVblog cheers for the reply! Yeah I've normally just browsed for tools and such to get it up. Last time it was a fancy arse solder pump. Gotta make a list of things I can add.
Sorry, stupid question, but why is it on a heat sink if it was insulated?
electrically isolated is the more apt term... its insulated electrically from the heatsink but still needs to radiate heat.
@@n2n8sda thanks, that makes sense. I was thinking plastic insulates heat too, but realise now it's probably not the case.
@@codersg Plastics are a poor conductor of heat, not an insulator of heat, but it is probably glass-filled plastic and glass is a better heat conductor than the plastic (still poor compared to metals). I believe you can have alumina-filled plastic which would be better still. Diamond would be the best material :)
Some sites also allow "fuzzy" searching with the tilde ~ character.
For parts, I always use Aliexpress. I don't even bother looking at the others anymore. 2€ for 10 pieces Delivered to Belgium. Usually that's about 11 days. Many different shops to choose from, possibility to chat with the seller and ask questions or negotiate. I usually order a bit more for my personal stock. Never been disappointed.
And you get good parts?, can you share some seller stores? 😊
@@gaberboraey5477 I don't look at the sellers, I just search for the part, then buy 5 or 10 pieces of the cheapest seller, sometimes from 2 or 3 sellers, just to increase my chances of getting it quickly. I do admit that I have had some bad experiences on Aliexpress in the past, bad parts or plain right scam, but that's only like 5 out of 1000s of orders so that's just life, and hey, getting scammed for $3-4 is just water under the bridge.
Off-topic question, but does anyone know what happened to the uSupply project? It looked so promising, but I haven't heard anything about it in almost a year.
An update video is on the agenda.
Why stop at * globs ?
Can't we have a fully regexp compatible search?
9:15 m-mega joules?
An interesting feature that I somehow figured out with Digikey is the use of the "pipe" OR operator. If you want to compare two parts in Digikey, copy the first part number Into a search window then add the pipe character | and then add the second part number. The search results will show results for both part numbers. You can then click on the check box for both part numbers and click on the compare button. Here's a video that explains it ua-cam.com/video/-U0WXC1onUY/v-deo.html
4:24 actually, you’ve pronounced “nomenclature” flawlessly! 😉
I used to work on stratus computer stuff and it was a dig to find some of the i/o memory chips for archaic retro compatibility issues that never stopped anything and had multiple workarounds. A week recreating a glitch on an X.25 card that was never used but would alert if it's lock-step logic went "Blah". I envied my colleague who worked on memory boards - Alpha particles!
its* goos-schteppened logic- ‘Bläh’.
Boy do I miss when RS did free shipping on everything... really sped up projects. Now I have to put it on the backburner until i've got enough stuff in my cart to make it worthwhile. Wouldn't be too bad if the stuff jaycar sold wasn't junk
You know, I've never payed attention to MOSFET part numbers and when you pointed out the nome- nom- er - nculture damn naming convention I grabbed my bits and odds box and had a look - and yeah it is fairly consistent. Wow now I've got an idea of some parameters of those buggers at a glance.. But hey Dave i think you should make a video explaining your expressions. Thought of this after i heard "shits and giggles" which i used to hear a lot in QLD but not so in NSW. Like for example what is the origin of "nothing burger" is it a nation wide expression. Anyhow could be fun for...well shits and giggles.
Cheers.
Why can I never find that 1000V 250A 1000MHz transistor I need for my own design...
Can't make those FETs arbitrarily large though. Bigger and faster FETs have higher gate drive power needs and at some point, incremental gate drive power will be greater than incremental switching and ON loss reductions. Bigger drivers for bigger FETs add quite a bit of cost too.
Sometimes you can use a % for a single caractor.
found it immediately at mouser. I normally take away the prefix to do a search. www.mouser.es/ProductDetail/512-FDPF18N50T
www.mouser.es/datasheet/2/308/FDPF18N50T-D-1808312.pdf
oh! i saw that you finally got it!...well, mouser has it either...
If I need specific parts for anything's the first address is Google to see, if it is generally available.
My second address is eBay. That led me even to a beefier part for the repair of my boiler controller.
All these websites lack of client/user experience.. Searching function is basic and has to be perfect or you loose lots of customers. I don't understand why they still haven't fixed all that..
must be "boomeritis"... I have it too.. but who designs the UI for a lot of the websites these days?? I too find them overly convoluted. Went through a very similar thing a couple of months ago when trying to find a replacement mosfet for one of these fancy new drills with the 3 phase brushless motors in them (that was trash picked too)... eventually caught on to mpn search and asterisk wildcards and found what i needed.