All the MOSFETs I have bought from AliExpress in the past turned out to be fake. I would advise to buy from mouser digikey or even lcsc(I use this) to get them because you don't pay that much more and you are sure to have good working parts.
@@TravisHardiman basically you mesure values the datasheet gives you. Usually the on resistance is not similar when those are fake. Another way is to check if it can handle the currents the datasheet says(be careful with overheating tho). One of the worst fakes i've got would saturate between 3 and 5 amps (they weren't even consistent) with a gate voltage of 10 volts while the datasheet said it would let up to 20 amps go through. Some other MOSFETs I've bought were supposed to have a on resistance of 0.05 ohm but when I measured it it was 0.3 ohm. If course they still can be useful for low power applications but for what I've got I could have bought something much cheaper from some trustworthy source
Probably one of the best videos you have made, certainly extremely useful. I have been doing electronics for 60 years (started with a crystal set). I also taught electronics for a few years in a secondary school and was an electronics examiner for secondary school electronics. Even now I regularly learn from your videos.
Thank you very much for your compliment. I showed it to my wife (to show off a little). Indeed I had fun making the video and it was quite hard to keep the focus and do not deviate too much.
Thank you so much for all these videos. I'm coming to the end of the design of a lora node that will deployed in 10'000s around the uk. You videos helped throughout the process of selection, evaluation, design and testing !
This has been an extremely educational video for me, thankyou. You've given it just the right mix of "how it works" theory, deciding how to compare different options for a project, and practical applications with microprocessors like Arduino. Of your hundreds of videos, this is one of my favourites.
This is the reason, why i love your Channel: like this, only Basic's and some suggestions.....i have learned something and make my next order much easier! Thanks,Andreas!
That is how I love it, too when I watch videos. BTW: I always tell my customers the difference between a consultant and an expert: The consultant has know-how (if it is a good one). The expert, in addition, has also an opinion ;-)
Although I knew a little bit about the differences between NPN and PNP, and high- and low-side switching, I didn't understand properly how it worked. Your video explains it so much better than nearly everything else out there.
Very useful video, Andreas. I've just taken a couple of hours to watch and re-watch it while taking notes from your video so to understand M0SFETs in detail. To be honest until now I have been only using BJTs! Thanks for your usual enlightenment and as always, helping me on my road to enlightenment!
Andreas, your video reminded of the moment in the '80's when I more or less abandoned bipolar for Mosfet devices, with a sigh of relief - so much easier to understand and to design with, and not just with digital switching. As I recall there were far fewer options in those days, which made selection easier than now. Thanks again for a great video.
Thanks for an amazingly straight-forwards and clear tutorial on transistors (with almost no maths!). I've always avoided transistors being too complicated to use, just sticking to resistors and capacitors for simple protection tasks, and probably wasting a lot of money on very simple pre-built sensor modules for my Arduino projects. This has given me the confidence to try start building my own more complicated discrete component circuits, I shall definitely be including your self power off circuit in some of my battery powered designs. Off to Amazon I go!
very useful video again! Recently I was searching exactly for the same topic and I could not find decent tutorial/description in the wild. Thanks again Andreas!
Transistors... the holy grail of modern electronics. Excellent video, it's been a few weeks since I subscribed to your channel and your videos are very interesting. I hope someday you make a video about your favorite books on electronics or any other topic of interest.
@Phil: The contrary is the case. Since we returned from our holiday, she decided to change her favorite place and always sit in front of my main screen ;-)
@Cristian: Welcome aboard the channel. This channel is purely about my interests. It is a hobby and I would not put this effort in it otherwise ;-) Concerning books: I am no more a "books" guy. The only three books about electronics I own are the one I showed plus the ARRL handbook and their Antenna Handbook.
I recently found myself in use of a BJTs since I needed to switch LEDs using 1.2 V signals. Maybe there exist FETs with such low gate-source voltages but it was easier for me to slap a BJT in the circuit to drive the LEDs. Fantastic video, just found your channel and I enjoy your videos.
Fabulously useful tutorial. It ís nice to be able to reduce inventory & 37k to 4 is a serious reduction. I am all for using the most common & low cost part I can find. I tried a similar exercise with surface mount capacitors & shot my self as frequency response, temperature response & piezo effect hurt me, but on the plus side I did learn a lot about capacitors. In my case it mostly came down to specific applications with needed well defined parameters & I now study data sheet & capacitors types very carefully. Thanks for sharing!
You are welcome. Of course, there is a reason for the 37000 parts. But because the usual maker does not have extended needs and maybe not every cent counts as for a production run, it was possible to narrow it down. For passives, it is a little different, as you mentioned.
Thank you Andreas. Good that I checked my parts bin before ordering the N-Channel mosfets. A dozen of FQP30N06L items are already there. They seem to do the same trick, just arround 2.5v, not 1.6v. And they are even cheaper on aliexpress :)
Very Small and Dirt Cheap = Two Aces for Four of a Kind Thanks for the video. And I don't consider anything from you as a waste of my time. Usually I watch more than once.
I've recently switched to smart switches and will likely not use mosfets anymore for experiments. They have current protection, ESD protection, temperature protection, back-EMF protection, etc. but they come with the disadvantage of a slightly higher price. See auips1021s and vnb20n07 for example. They are typically used in automotive applications, replacing the mechanical relays, and they come in high-side variants as well. Perhaps an idea for a future video, exploring these options.
I never heard of them. I found the datasheet for one of them, and it's described as "FULLY AUTOPROTECTED POWER MOSFET", so they are still MOSFETs with more extra protection? They seem like a nice component to have.
I also did not know them. They have a few additional components on the chip. I assume they are not easy to get from AliExpress. At least when I searched for them. So you probably have to buy them from Digikey or so.
That was a great video about transistors. Still keeping old BJT on survival kit just in case the FET's are gonne. Also keep resistors of know values like 100K , 10K, 4k7, 470, 220 2k2... plug digital pin to base, gate. Other components usefull for transistors: LM317,LM78XX, OPAMPS, NE555 ( use this instead of arduino for the first time maybe :D ), capacitors (10nF, 100nF, 1uF, 10uF, 1000uF...) .. edit .. pen, paper and calculator
Of course the complete survival kit is bigger, you are right. I only focused on transistors because otherwise it would have become a Netflix series ;-)
I wish you would have released this video about 3 years ago. Great info that I had to scrape together through much reading and a few test as I was playing with 5V and 3.3V devices at the time and logic level then was more aimed at 5V devices. Always check the threshold voltage and look at the datasheets is what I learned as even some 'logic level' mosfets aren't really logic level to be fully on (and not wasting power/producing heat).
Excellent video! Thanks for taking the time to experiment, video, edit, and publish. It is a big job, and I think you did a great job for all phases of this video!
Regarding fake parts, it could also be that the factory producing the "genuine" ones produced too many for the promised order to the vendor, and just looked to liquidate them to offset the cost of the overrun. Could also be quality control cast-offs, or unbadged versions to sidestep copyright. None of those are necessarily good things in the grand scheme. But, as a home hobbyist experimenting/prototyping in small volumes, if it meets the spec, it meets the spec. If I'm looking to properly repair something, I'll go to an authorized source and spend the money to be sure I'm getting the right part.
I hardly use BJTs. So I do not have a lot of experience. For diodes it is simple: Either I use any standard diode or, if I need a smaller voltage drop, a Schottky diode. Also here, I do not design switching power supplies and stuff like that.
I got myself some IRF3205 from Aliexpress a while ago (1.70€ for 5 of them) and are absolutely overkill in a TO220 package, 110A max current, and i believe it's 4V to fully trigger it. Also, 8mΩ, so i'd say it's impossible to overheat it with a normal diy project (at least, the ones with a simple PSU or battery)...
@@AndreasSpiess Yes, that's why it's perfect for me, i only have arduino nano, so all my high signals are 5v... it was mostly to comment the good results with products from Aliexpress (also arduino source)
Awesome! I understand these a little better. I'll have rewatch again later to get more sunk into my brain cells. 😉 Thanks for the detailed descriptions with practical application right along with the info. 👍😎
11:11 “shit”. I’m glad you didn’t beep that away as for us non-native speakers (and a lot of native speakers, I guess) it’s not as offensive as the overly prudish UA-cam algorithm is programmed to.
@@kbouwman64 he was watching the news on TV. Politicians had just increased the taxes for the working class, while allowing tax avoidance for the rich. The usual stuff.
Over 40 years ago, when I went to university, digital electronics (TTL) were just getting popular. Frequency were still low and MOSFETs did not really exist. The whole semester was sent studying "characteristic curves" with no mention of switching circuits. ("Saturation" was BAD !) Boy, how times have changed !
I would love to see a "part 2" of this, covering the why your "survival kit" contain as many through-hole transistor as it does (i.e. what characteristics were important to your selection). I am too old (shaky hands) to even try to solder SMD (like that young wiper snapper over on GreatScott channel.) Also maybe some "tricks" like using a N-channel FET as a high side driver with a voltage doubler or using a "driver" transistor for power MOSFETs that require higher Vgs.
@@AndreasSpiess In the middle 80s, while writing embedded code (in assembler), I tried to convince the guys designing circuits that MOSFET were the way of the future, replacing Darlintons. The obvious first benefit was low power dissipation, but cost was still too high (when you are making over 1 million devices). The Rds On values today are AMAZING !
Looks like that you really like FET's but I am learning and starting with BJT transistors and when I master the BJT then my next move is mosfets and JFets to start with switching circuits
Good Video. Over the Years I've managed to gather a rather substantial Bench Stock. One that rivaled the Radio Shack we once had in town. LOL All the basic common Transistors , resistors , Op Amps and more. FET's are a soft point. I have a rather good selection at hand but lacking many I would like. Tons of PCB creation materials and supplies. Gadgets, mini meters and more. It may take me a day to locate what I want but chances are I have it.
We all have our stocks. And finding is sometimes a challenge. I usually use my AliExpress orders to check if I should have it. Thi increases the motivation for searching...
@@AndreasSpiess BINGO ! I have somewhat the same system. I have a Word Pad document holding everything weird or of items on hand. Everything else is covered by my Parts ordered log of various vendors like Tyda, Banggood and others. A quick search with key words usually does the trick. Following that at least I would know which box it should be in. LOL Boxes include New Electronic Parts, Used, Current Project items, Test equipment related, Arduino Related and ect. My project box has overflowed into various boxes. And then there is the SOME DAY Box. LOL
One very interesting part for switching is the ULN2803 that I use often. 8 NPN transistors with base resistor and flyback diode in a DIP package. 0.5A per channel and 2.5A total maximum.
I've worked with transistors from the days of the CK722 on. So, I may not go back as far as you do. I remember when the U.S. was putting out a bunch of fair silicon transistors with not so close parameters, pretty much all with numbers starting with 2nxxxx. Then , the Japanese started putting out transistors with 2SBxxxx. or 2SCxxxx , these transistors had such tight parameters that if a circuit was designed around them, you quite often had to get the same exact transistor. Made rapiers take a little longer but the circuits worked very well. This was especially important for the Stereos coming out of Japan which had direct connected amplifiers (this was before the system came out with those large plastic amplifier modules ) . Amplifiers which were being repaired should have all been repaired with exact replacements made in Japan. But, that didn't always happen, the amps would put out sound but be unbalanced and distorted and in not too long blow up again. Now we have Chinese manufacturing which is a mix of U.S. engineering and who knows what ! Oh well. Back to the video.
It seems you have a lot of experience with these parts! Indeed, not only with transistors, the Japanese once challenged the "western" manufacturers. I remember also when the first Japanese Motorcycles or cars hit the road. Their tolerances also were much tighter. But the downside of good quality parts is that they do not mix well with lower quality.
Thank you so much for this video, as you had mentioned in a previous video, you created a video that you would like to watch. I'd say this video showcases THE fine art of teaching.
I wanted to make a lcsc bom with all common resistors and capacitors for a one click workspace restocking but I found it more useful to order those kit bags and then the stuff that I used up
This should be "Recommended Reading" for every EE beginner (now what’s RR today with videos?). An excellent overview for everyone starting out with transistors! Kudos, Andreas! I wish my teachers back then (~40 years ago) would have been teaching that efficiently … :-) Btw, you might have mentioned the function of the body diode in power MOSFETs for newbies. ;-)
Was just mentioning it because it got shown on some of the schematics and a newbie might wonder. ;-) We oldtimers would probably use an external Schottky as a flyback anyways … ;-)
Nicely explained, Andreas! I would disagree with you on "totally skipping BJTs" though - A baggie each of 2N2222 and 2N2907 is handy for emitter-followers and as easy gate-drivers for MOSFETs when you need a gate-drive-current more than 20mA. Definitely beyond the scope of _this_ video, but have you dabbled with "depletion mode" MOSFETs? These are _on_ at zero volt (i.e. v_gs_th
This video was already 27 minutes, much more than my usual budget. I knew from the beginning that I have to focus, focus, focus on the really needed things for a "normal" Maker. But of course, BJTs are useful. this is why I covered them. No, I never had depleton mode FETs, but I read about htem during the preparation of that video.
For a trough hole perspective... - IRF3708 is really the best, except TO220 is bulky; - I would have a look at "CJMCU-4599" ready made package; - With its many limitations, 2N7000 can be nice too.
With my office boss the alternative option works. At home however i keep getting into situation where one option was discarded by me, remaining good case gets discarded by wife.. Awesome video Andreas.I wish i had this when i was studying electronics 20 years ago. !!
IRF3708 are really bulky and as you mentioned an overkill. I use BS170 , its TO-92 package in more handy, its Gate source threshold voltage is 2.1 volts, very suitable for ESP32 and it can deliver around 500 MA. Best of everything.
They are sold as small signal FETs and have a quite high Rds on. So they get probably hot qute fast. But of course, it is a possibility. I have them also here, but usually use SMDs instead of them.
nice simplified tutorial! However, even bipolar transistors have a place in switching... they are usually faster in turning on, but slower in turning off, especially when driven with high base currents. Also bipolar transistors are a bit more robust against static charges or high-voltage transients.
As I also commented for the next video: always put a series resistor ( acouple of hundred ohms) into the gate lead of the MOSFET as well in order to protect your Arduino (or whatever) from a catastrophic failure in the MOSFET.
Everything has its place in the world. I wanted to reduce to the Max. I think I mentioned the gate resistor intros video in the switching section. Absolutely needed.
@@AndreasSpiess I absolutely agree with your minimalistic selection. Regarding the series resistance you later recommended it in the video - but then in your next video you complain over the burnt-up potentiometers which seems to indicate that you yourself are not using them... And you didn't show them in your connection diagrams...
@@AndreasSpiess yes, absolutely, it was only destroyed, because the FET failed, and with the additional series resistance between Gate and potentiometer wiper the potentiometer (or the Arduino) would be protected from this destructive power. In normal operation the serial resistance will slightly slow down the switching speed with a time constant of R times Cgate
Great advice as always. In video 290 you showed your transistor tester - very handy to see what that device is. I still use mine for measuring the beta of NPNs - but I am older than you! Afraid of high voltages? As an ex RF engineer, I find rf burns far nastier!
Great video :) when first messing with mosfet, I wish I had it... I managed to figure out what I needed, but it feels so much... safer? when someone shows the way
I'd reccomend SO8 mosfets. They are able to have low resistances for a fraction of cost of to-220. Also, once I bought AO3400A mosfets on Ali, which supposed to have 25-50 mOhm Rds(on). I checked their resistance and it was 5 freaking ohms...
You really have to add the darlington transistor to a survival kit to my opinion, I use the ULN2003A chip for all my Raspberry Pi and Arduino projects because with these I don't have to think about adding a current limiting resistor on the input of the chip, it's already built-in. There are also flyback diodes built-in so with the same chip I can drive inductive loads like a relais without any problem. And when I need to switch for example a power LED I can simply tie some inputs and output pins together, I can go up to 50 volt maximum which is more than enough for almost any project. I think that when you only have the ULN2003A chip which is a 7 channel darlington pair you'll have a more than enough capable survival kit so this is the only thing you really need to my opinion.
@@AndreasSpiess The collector current for a single output is 500mA so it's capable enough. I looked it up in the datasheet it says that in some cases you can go up to 2.5Amp.
@@AndreasSpiess I know it's an electronics IoT maker channel; but the pacing the clips is really good; the explanations follow a logical progression with strong emphasis on understanding - I'm really curious how you plan out scripts for your videos; and most importantly the summaries; a nice wrap to reinforce learning :)
I think BJT still have a place in the hobbiest's world. A power bjt is typically going to be cheaper than a similar power fet with a low-enough Vgs to be easily implemented without driver and also much more robust than FETs from an ESD perspective, you'd have to be trying pretty hard to destroy a good old 2n2222 NPN but a 2n7002 N-Fet is fairly readily killed. And while you don't go into linear, driving LEDs is a classic case where a BJT is useful for it's relatively simple means to select an output current, good enough for an LED, without needing any feedback or additional current limiting, just take the Hfe and calculate the base current, close enough job done. Anyway, at least a baggie of 2n2222 and a few BD139 should be in every parts draw if you ask me.
Re: Anti-static measures. To be effective doesn't the anti-static mat have to be grounded? It is not enough to have an anti-static wrist-band and mat. Though this is not a video on ESD I suggest that it is misleading as stated.
I know the pick and place machines produce a lot of wastage (they cut a good size of before feeding). I've wondered whether the 'fake' ones could be recovered components (they have a sink to catch the trimmed tape ), or excess sent by customers who are having boards assembled.
I would not call your examples "fakes" because they seem to be genuine parts and they should work ok. It is well possible that they try to sell excess material via ebay or AliExpress. Which is a good idea, I think.
20:47 I was wondering if the push button could go between the PNPs gate and ground in this schematic... wouldn't that be better, for example if you're switching a load parallel to the µC ? but its a really nice idea to do it this way... minimal parts.
As always Andreas, you manage to pull it off. I really didn't need to see a video about transistors I thought, but you are entertaining, and as always I picked up some useful info. But I have one question, the girls that you go out with, they newer ask where the transistors come from, in my experience girls are really focused on where especially the capacitors and transistors come from :-)
I tried to give the video a slightly different twist because there are enough videos out which explain how they work. BTW: I did not say they did not ask for. They just were happy with the answer ;-) This citation is from the famous UA-camr AvE
@@AndreasSpiess Thanks for taking the time to answer, keep up the good work. Sunday morning newspaper, not any more, now it Sunday morning and new video from the brilliant guy with the Swiss accent.
Thank you for sharing your "kit". If you have my age ( according to your UA-cam name) then you probably also were "socialized" with BJTs. But those FETs are really amazing!
Such a useful video, that I must watch again. An incredible amount of material in your videos - a true professional! In the early 1960s when the latest thing was a germanium transistor in a metal case, we used to buy them in bulk and then have a group of us testing them to find the good ones. Maybe you could do the same? How good is your wife with a transistor tester? Thanks!
As I mentioned, last week I built a transistor curve tracer. This was part of the motivation for this video. Comments about fake parts on AliExpress triggered now my next project: Test parts in my bin for specifications. We will see how far I get...
i also love to keep different types of transistors. don't have as many as you have though. but i even went beyond the chinese sellers and ordered some germaniums from german sellers just to get hold of the obsoletes, and use them in audio applications. 😀
Hi Andreas, great video as usual. Thanks! One small remark: @8:56 you show a diagram without the base resistor, I hope your viewers will not try it like that, earlier in the video you already nicely explained and showed us why :-).
AliExpress sellers sometimes buy defective parts, which did not pass the manufacturer checks. I had some IRLML6402, which always passed current and some MPU6050 with one axis always showing maximum acceleration. To avoid faulty parts you should look at the item's photo and the description. There must be a photo of the component you looking for and not a generic picture of some random component, and at least type of the component must be written in the description. If it is so, it is 90% not defective or fake.
@@AndreasSpiess Yes. lolz I thought it would come in handy. I like to play and make things. I do silly things like make logic gates out of them or use them in small projects. I guess it really depends on what you are doing. Well I now know how to connect an esp to super led. ;)
Great video as always. In my experience of buying MOSFETs on AliExpress N-Channel ones seem to be ok. Cheap P-Channel ones are almost invariably fake. Genuine P-Channel ones seem to be 3-5 times the price of N-Channel ones.
After all the discussions in the comments I will make a video where I test my FETs to see, how many are faked. No fancy JFETs, just regular MOSFETS used in this video. The fancier the bigger the risk, I think...
Do any of the transistors in the survival kit need a heat dissipation clamp when soldering? The NPN/PNP transistors I first used decades ago required a clamp to dissipate heat to prevent damage. To be honest, I have not done a lot of projects.
No BJTs in the survival kit even though you said FETs are sensitive to small charges, therefore dependant of ESD equipmenet. Isnt it a good idea to also have some BJTs which will be useable even if you dont have ESD at hand?
Hi Andreas, really great. Could you please post a recommendation for an ESD mat/kit? Or is it maybe a subject for a short video? Thanks and have a save trip!
My survival kit: - 2N7000 - N-MOSFET, great for digital stuff - BC547 - NPN BJT - The Swiss Army Knife of transistors - BC558 - PNP BJT, complement to the BC547 - PN2222A - NPN BJT - If I need to handle a little more current, this is a good choice. SMD is evil thus not part of the survival kit. Sometimes necessary evil, but not something I stock. Missing from my survival kit is a good TO-92 P-MOSFET. It seems there exists no good complement to the 2N7000, you either have to go SMD or use power mosfets. Therefore in Arduino projects, I often resort to the BC558 BJT. It costs a resistor to protect the base, but going SMD or power mosfet is less elegant than using a resistor.
Andreas, could you provide an alternative to the IRF3708? I looked it up at Mouser and it seems to be EOL and has long delivery times. Thanks for your videos, they really help me realising my projects :)
Is it possible that you use the Depletion MOSFET symbol at some places? The most common symbol for NMOS and PMOS use a discontinuous line for the chanel to add emphasis that there is NO current passing through when Vgs = 0. The LTspice diagrams are ok in that aspect, but the photocopies seem wrong: using a continuous line for the chanel, that would indicate a Depleted mode MOSFET ( a DMOS ) allowing the current to pass through when Vgs = 0 (which makes them useful for current limiting montage, as example).
I used the standard symbols of frizzing. I do not care too much about them. Too complicated for me if I look at the variants shown on one of my slides.
Hello, Could you make a video like this for OPAMP? when we should use which opamp? surely most of the viewers have questions like me. video for transistor selection was Excellent, Thanks
@@AndreasSpiess you are right! but your video about transistors are Unique! your compare and how to select best transistor. about op-amp viewers need same for sure. help me to find if available any place. again thanks for your nice video. god bless u.
The arrows' tips should end on N-type material. For N-channel FETs this means the arrow should point toward the channel. For P-channel FETs it should point away.
@@AndreasSpiess Here are the worldwide IEEE standards: ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7407262 Someone should point out "frizzing's" error. Since I am unfamiliar with them, I nominate you.
Unfortunately, I had to re-upload this video because I screwed up and discovered it too late. Thanks, Ristomatti for giving me a warning.
They're all good enough for the girls we go out with ;-)
The level of detail and clarity in your productions always goes above and beyond. Thank you!
@Aaron: Thank you!
All the MOSFETs I have bought from AliExpress in the past turned out to be fake. I would advise to buy from mouser digikey or even lcsc(I use this) to get them because you don't pay that much more and you are sure to have good working parts.
@@renaudfensie3020 how can you tell if they are fake?
@@TravisHardiman basically you mesure values the datasheet gives you. Usually the on resistance is not similar when those are fake. Another way is to check if it can handle the currents the datasheet says(be careful with overheating tho). One of the worst fakes i've got would saturate between 3 and 5 amps (they weren't even consistent) with a gate voltage of 10 volts while the datasheet said it would let up to 20 amps go through. Some other MOSFETs I've bought were supposed to have a on resistance of 0.05 ohm but when I measured it it was 0.3 ohm.
If course they still can be useful for low power applications but for what I've got I could have bought something much cheaper from some trustworthy source
Probably one of the best videos you have made, certainly extremely useful. I have been doing electronics for 60 years (started with a crystal set). I also taught electronics for a few years in a secondary school and was an electronics examiner for secondary school electronics. Even now I regularly learn from your videos.
+1
yes
Stephen Cook
Wow, that’s a very nice thing to say and it must be one of best compliments Andreas ever got and well deserved too. Thank you.
Thank you very much for your compliment. I showed it to my wife (to show off a little).
Indeed I had fun making the video and it was quite hard to keep the focus and do not deviate too much.
I can only second this
Excellent video as always Andreas, and beautifully explained.
Thank you! There are many videos about transistors around (including yours, if I remember right). This is why I thought I want to be very practical...
Andreas, I'm 44 years old, but when I grow up I want to be just like you.
Thank you for your compliment! I had to share it with my wife :-)
@b gg Me too and I'm 70
Hah! I'm 42, and I do my best to _avoid_ growing up! ;)
“It takes a long time to become young”
Picasso
I think this is a great definition of the transistors and the function of each. Thanks for the time and effort to make this video.
You are welcome!
You sir are an excellent teacher. Thanks for a perfect explanation of the basics of transistors.
Thank you!
Thank you so much for all these videos. I'm coming to the end of the design of a lora node that will deployed in 10'000s around the uk. You videos helped throughout the process of selection, evaluation, design and testing !
You are welcome! Good luck and I hope you did not purchase any "fake" components for your product...
This has been an extremely educational video for me, thankyou. You've given it just the right mix of "how it works" theory, deciding how to compare different options for a project, and practical applications with microprocessors like Arduino. Of your hundreds of videos, this is one of my favourites.
Thank you for your nice words!
This is the reason, why i love your Channel: like this, only Basic's and some suggestions.....i have learned something and make my next order much easier! Thanks,Andreas!
That is how I love it, too when I watch videos.
BTW: I always tell my customers the difference between a consultant and an expert: The consultant has know-how (if it is a good one). The expert, in addition, has also an opinion ;-)
Although I knew a little bit about the differences between NPN and PNP, and high- and low-side switching, I didn't understand properly how it worked. Your video explains it so much better than nearly everything else out there.
Thank you!
Very useful video, Andreas. I've just taken a couple of hours to watch and re-watch it while taking notes from your video so to understand M0SFETs in detail. To be honest until now I have been only using BJTs! Thanks for your usual enlightenment and as always, helping me on my road to enlightenment!
You are welcome! FETs are very good parts, especially for switching applications. Their very low Rds on is sometimes as they would not exist...
Andreas, your video reminded of the moment in the '80's when I more or less abandoned bipolar for Mosfet devices, with a sigh of relief - so much easier to understand and to design with, and not just with digital switching. As I recall there were far fewer options in those days, which made selection easier than now.
Thanks again for a great video.
The current selection is really awesome, I think. But a lot of the datasheets are from the 1990s. So some of the common parts seem to be "evergreens"
A video I didn't know I needed to watch. Those are always the best... Thanks, Andreas.
You are welcome! I hope more people will do the same.
Thanks for an amazingly straight-forwards and clear tutorial on transistors (with almost no maths!).
I've always avoided transistors being too complicated to use, just sticking to resistors and capacitors for simple protection tasks, and probably wasting a lot of money on very simple pre-built sensor modules for my Arduino projects.
This has given me the confidence to try start building my own more complicated discrete component circuits, I shall definitely be including your self power off circuit in some of my battery powered designs.
Off to Amazon I go!
Great! That was the purpose of this video. To make it as simple as possible (but not simpler). As another guy with a Swiss accent said (Einstein)...
very useful video again! Recently I was searching exactly for the same topic and I could not find decent tutorial/description in the wild. Thanks again Andreas!
Thank you! That is what I did too before I started the video on a so common topic like transistors.
Transistors... the holy grail of modern electronics. Excellent video, it's been a few weeks since I subscribed to your channel and your videos are very interesting. I hope someday you make a video about your favorite books on electronics or any other topic of interest.
That will be his cat then, who must be on holiday as not in the last two videos....
@Phil: The contrary is the case. Since we returned from our holiday, she decided to change her favorite place and always sit in front of my main screen ;-)
@Cristian: Welcome aboard the channel. This channel is purely about my interests. It is a hobby and I would not put this effort in it otherwise ;-)
Concerning books: I am no more a "books" guy. The only three books about electronics I own are the one I showed plus the ARRL handbook and their Antenna Handbook.
It's usually most important to have a low on resistance and low gate charge if you want high speed hard switching
Yes.
Love it, just what I was looking for. Densely packed with informative content and I love the touch of humour to keep things light 11:10
:-)
I recently found myself in use of a BJTs since I needed to switch LEDs using 1.2 V signals. Maybe there exist FETs with such low gate-source voltages but it was easier for me to slap a BJT in the circuit to drive the LEDs.
Fantastic video, just found your channel and I enjoy your videos.
Welcome aboard the channel!
Thank you Andreas
You are welcome!
Thanks! I love your practical teaching style.
You are welcome!
Fabulously useful tutorial. It ís nice to be able to reduce inventory & 37k to 4 is a serious reduction. I am all for using the most common & low cost part I can find. I tried a similar exercise with surface mount capacitors & shot my self as frequency response, temperature response & piezo effect hurt me, but on the plus side I did learn a lot about capacitors. In my case it mostly came down to specific applications with needed well defined parameters & I now study data sheet & capacitors types very carefully. Thanks for sharing!
You are welcome. Of course, there is a reason for the 37000 parts. But because the usual maker does not have extended needs and maybe not every cent counts as for a production run, it was possible to narrow it down. For passives, it is a little different, as you mentioned.
I love your videos. You help me understand things I’ve always been curious about but couldn’t quite wrap my head around. Thanks!
You are welcome!
Thank you Andreas. Good that I checked my parts bin before ordering the N-Channel mosfets. A dozen of FQP30N06L items are already there. They seem to do the same trick, just arround 2.5v, not 1.6v.
And they are even cheaper on aliexpress :)
A dozen will last for a while, I think...
I like all of your videos but the ones like this one are exceptionally helpful to me.
Glad to read that. I hoped it will be of benefit for many Makers when I made it.
Very Small and Dirt Cheap = Two Aces for Four of a Kind
Thanks for the video. And I don't consider anything from you as a waste of my time. Usually I watch more than once.
Thank you for your nice words!
I've recently switched to smart switches and will likely not use mosfets anymore for experiments. They have current protection, ESD protection, temperature protection, back-EMF protection, etc. but they come with the disadvantage of a slightly higher price. See auips1021s and vnb20n07 for example. They are typically used in automotive applications, replacing the mechanical relays, and they come in high-side variants as well. Perhaps an idea for a future video, exploring these options.
I never heard of them. I found the datasheet for one of them, and it's described as "FULLY AUTOPROTECTED POWER MOSFET", so they are still MOSFETs with more extra protection? They seem like a nice component to have.
I also did not know them. They have a few additional components on the chip. I assume they are not easy to get from AliExpress. At least when I searched for them. So you probably have to buy them from Digikey or so.
That was a great video about transistors. Still keeping old BJT on survival kit just in case the FET's are gonne. Also keep resistors of know values like 100K , 10K, 4k7, 470, 220 2k2... plug digital pin to base, gate. Other components usefull for transistors: LM317,LM78XX, OPAMPS, NE555 ( use this instead of arduino for the first time maybe :D ), capacitors (10nF, 100nF, 1uF, 10uF, 1000uF...) .. edit .. pen, paper and calculator
Of course the complete survival kit is bigger, you are right. I only focused on transistors because otherwise it would have become a Netflix series ;-)
I wish you would have released this video about 3 years ago. Great info that I had to scrape together through much reading and a few test as I was playing with 5V and 3.3V devices at the time and logic level then was more aimed at 5V devices. Always check the threshold voltage and look at the datasheets is what I learned as even some 'logic level' mosfets aren't really logic level to be fully on (and not wasting power/producing heat).
As you mention: 3 years ago many makers used 5v logic.
Excellent video! Thanks for taking the time to experiment, video, edit, and publish. It is a big job, and I think you did a great job for all phases of this video!
Thank you for your nice words!
Hi Andreas, great video and well explained. Mostly i go for safe and use a ULN2803 ic but maybe after seeing this video i have to expand my horizon
These ULN are good chips. But sometimes an overkill...
Great video Andreas. Just saved me from getting ideas that are fancier than my needs. Thanks.
You are welcome!
Regarding fake parts, it could also be that the factory producing the "genuine" ones produced too many for the promised order to the vendor, and just looked to liquidate them to offset the cost of the overrun. Could also be quality control cast-offs, or unbadged versions to sidestep copyright. None of those are necessarily good things in the grand scheme. But, as a home hobbyist experimenting/prototyping in small volumes, if it meets the spec, it meets the spec. If I'm looking to properly repair something, I'll go to an authorized source and spend the money to be sure I'm getting the right part.
The discussions on "fake" parts sparked my interest and I decided to dig a little into it..
@@AndreasSpiess I look forward to your conclusions then!
Very good Andreas very good. I was planning to get some info somewhere and got almost everything I needed at watching this and having dinner at work
3-in-1. Earning, eating, and learning. What a productivity ;-)
@@AndreasSpiess indeed, I don't think there's anyway to get more productivity 👌
(Also note, Sunday work 😄)
Outstanding video!! Can you do a similar video for linear transistors? And maybe then diodes and capacitors?
I hardly use BJTs. So I do not have a lot of experience. For diodes it is simple: Either I use any standard diode or, if I need a smaller voltage drop, a Schottky diode. Also here, I do not design switching power supplies and stuff like that.
I got myself some IRF3205 from Aliexpress a while ago (1.70€ for 5 of them) and are absolutely overkill in a TO220 package, 110A max current, and i believe it's 4V to fully trigger it. Also, 8mΩ, so i'd say it's impossible to overheat it with a normal diy project (at least, the ones with a simple PSU or battery)...
According the data sheet it is probably better for 5 volt then for 3 volt logic.
@@AndreasSpiess Yes, that's why it's perfect for me, i only have arduino nano, so all my high signals are 5v... it was mostly to comment the good results with products from Aliexpress (also arduino source)
Awesome! I understand these a little better. I'll have rewatch again later to get more sunk into my brain cells. 😉 Thanks for the detailed descriptions with practical application right along with the info. 👍😎
This video is also planned as a reference. It is quite dense, I have to admit.
11:11 “shit”. I’m glad you didn’t beep that away as for us non-native speakers (and a lot of native speakers, I guess) it’s not as offensive as the overly prudish UA-cam algorithm is programmed to.
I always thought that is what we all produce on a regular basis. So it cannot be bad. Otherwise we would have to stop it ;-)
@@AndreasSpiess My father used to say: "if shit were gold, poor people would be born without an asshole".
@@copernicofelinis So I am wondering...What was your father doing or thinking about that made this the thing he wanted to say? :D
@@kbouwman64 he was watching the news on TV. Politicians had just increased the taxes for the working class, while allowing tax avoidance for the rich. The usual stuff.
@@AndreasSpiess, If it was that good for us, we would keep it inside, not throw it out. However it is good for the plants.
Over 40 years ago, when I went to university, digital electronics (TTL) were just getting popular. Frequency were still low and MOSFETs did not really exist. The whole semester was sent studying "characteristic curves" with no mention of switching circuits. ("Saturation" was BAD !) Boy, how times have changed !
Definitively (I was there from 1977-1982). This is why this video is also good for old boys. These FETs are really great little parts!
I would love to see a "part 2" of this, covering the why your "survival kit" contain as many through-hole transistor as it does (i.e. what characteristics were important to your selection). I am too old (shaky hands) to even try to solder SMD (like that young wiper snapper over on GreatScott channel.) Also maybe some "tricks" like using a N-channel FET as a high side driver with a voltage doubler or using a "driver" transistor for power MOSFETs that require higher Vgs.
@@AndreasSpiess In the middle 80s, while writing embedded code (in assembler), I tried to convince the guys designing circuits that MOSFET were the way of the future, replacing Darlintons. The obvious first benefit was low power dissipation, but cost was still too high (when you are making over 1 million devices). The Rds On values today are AMAZING !
I use throughhole parts mainly for experimentation on breadboards. On PCBs I prefer SMD. Much faster and easier to handle for me.
Looks like that you really like FET's but I am learning and starting with BJT transistors and when I master the BJT then my next move is mosfets and JFets to start with switching circuits
That is a good plan. I do not "like" them. The requirement of this video was digital switching. And for that, FETs are very good.
the 27:49 flies so fast - i didn't notice that this is such a long video ... could sit even longer and listen to that interesting stuff
Thank you for your nice words! I experienced the duration when producing it. It took quite long for this one ;-)
@@AndreasSpiess i think 1 min video is 10 to 30 min production time ... thank you for you time, that's a big gift to the community!
Unfortunately it is more :-(
Good Video. Over the Years I've managed to gather a rather substantial Bench Stock. One that rivaled the Radio Shack we once had in town. LOL All the basic common Transistors , resistors , Op Amps and more. FET's are a soft point. I have a rather good selection at hand but lacking many I would like. Tons of PCB creation materials and supplies. Gadgets, mini meters and more. It may take me a day to locate what I want but chances are I have it.
We all have our stocks. And finding is sometimes a challenge. I usually use my AliExpress orders to check if I should have it. Thi increases the motivation for searching...
@@AndreasSpiess BINGO ! I have somewhat the same system. I have a Word Pad document holding everything weird or of items on hand. Everything else is covered by my Parts ordered log of various vendors like Tyda, Banggood and others. A quick search with key words usually does the trick. Following that at least I would know which box it should be in. LOL
Boxes include New Electronic Parts, Used, Current Project items, Test equipment related, Arduino Related and ect. My project box has overflowed into various boxes. And then there is the SOME DAY Box. LOL
Good work Andreas, thanks.... nicely concise...
Thank you!
One very interesting part for switching is the ULN2803 that I use often. 8 NPN transistors with base resistor and flyback diode in a DIP package. 0.5A per channel and 2.5A total maximum.
A nice part, I agree. I used it in one of my projects.
I've worked with transistors from the days of the CK722 on. So, I may not go back as far as you do. I remember when the U.S. was putting out a bunch of fair silicon transistors with not so close parameters, pretty much all with numbers starting with 2nxxxx. Then , the Japanese started putting out transistors with 2SBxxxx. or 2SCxxxx , these transistors had such tight parameters that if a circuit was designed around them, you quite often had to get the same exact transistor. Made rapiers take a little longer but the circuits worked very well. This was especially important for the Stereos coming out of Japan which had direct connected amplifiers (this was before the system came out with those large plastic amplifier modules ) . Amplifiers which were being repaired should have all been repaired with exact replacements made in Japan. But, that didn't always happen, the amps would put out sound but be unbalanced and distorted and in not too long blow up again. Now we have Chinese manufacturing which is a mix of U.S. engineering and who knows what ! Oh well. Back to the video.
It seems you have a lot of experience with these parts! Indeed, not only with transistors, the Japanese once challenged the "western" manufacturers. I remember also when the first Japanese Motorcycles or cars hit the road. Their tolerances also were much tighter. But the downside of good quality parts is that they do not mix well with lower quality.
Thank you so much for this video, as you had mentioned in a previous video, you created a video that you would like to watch. I'd say this video showcases THE fine art of teaching.
Thank you very much for your nice words!
I wanted to make a lcsc bom with all common resistors and capacitors for a one click workspace restocking but I found it more useful to order those kit bags and then the stuff that I used up
I also like assortments in boxes a lot ;-)
This should be "Recommended Reading" for every EE beginner (now what’s RR today with videos?). An excellent overview for everyone starting out with transistors! Kudos, Andreas!
I wish my teachers back then (~40 years ago) would have been teaching that efficiently … :-)
Btw, you might have mentioned the function of the body diode in power MOSFETs for newbies. ;-)
Thank you!
The video was already 27 minutes. And the body diode is a specialty in my eyes...
Was just mentioning it because it got shown on some of the schematics and a newbie might wonder. ;-) We oldtimers would probably use an external Schottky as a flyback anyways … ;-)
Nicely explained, Andreas! I would disagree with you on "totally skipping BJTs" though - A baggie each of 2N2222 and 2N2907 is handy for emitter-followers and as easy gate-drivers for MOSFETs when you need a gate-drive-current more than 20mA. Definitely beyond the scope of _this_ video, but have you dabbled with "depletion mode" MOSFETs? These are _on_ at zero volt (i.e. v_gs_th
This video was already 27 minutes, much more than my usual budget. I knew from the beginning that I have to focus, focus, focus on the really needed things for a "normal" Maker. But of course, BJTs are useful. this is why I covered them.
No, I never had depleton mode FETs, but I read about htem during the preparation of that video.
Hi Andreas. A superb video, thanks a lot!
You are welcome
For a trough hole perspective...
- IRF3708 is really the best, except TO220 is bulky;
- I would have a look at "CJMCU-4599" ready made package;
- With its many limitations, 2N7000 can be nice too.
The Si4599 is a real catch! Than you for mentioning it. Then you can reduce the Survival Kit :-)
With my office boss the alternative option works. At home however i keep getting into situation where one option was discarded by me, remaining good case gets discarded by wife.. Awesome video Andreas.I wish i had this when i was studying electronics 20 years ago. !!
We all have to solve our problems ;-) Thank you for your nice words!
That was a really good one !!! THANKS !
You are welcome!
Nice video 👍
🙂
Thank you!
I use the BSS138 very often to drive LEDs and relais etc. with 3.3V. It is my favorite small FET
Good choice. I also have a few of them here. They are also quite small...
Only smd (SOT-23) but thats no disadvantage. Use them also for logic level shifting
IRF3708 are really bulky and as you mentioned an overkill. I use BS170 , its TO-92 package in more handy, its Gate source threshold voltage is 2.1 volts, very suitable for ESP32 and it can deliver around 500 MA. Best of everything.
ands it P-channel equivalent BS250
They are sold as small signal FETs and have a quite high Rds on. So they get probably hot qute fast. But of course, it is a possibility. I have them also here, but usually use SMDs instead of them.
nice simplified tutorial!
However, even bipolar transistors have a place in switching... they are usually faster in turning on, but slower in turning off, especially when driven with high base currents. Also bipolar transistors are a bit more robust against static charges or high-voltage transients.
As I also commented for the next video: always put a series resistor ( acouple of hundred ohms) into the gate lead of the MOSFET as well in order to protect your Arduino (or whatever) from a catastrophic failure in the MOSFET.
Everything has its place in the world. I wanted to reduce to the Max. I think I mentioned the gate resistor intros video in the switching section. Absolutely needed.
@@AndreasSpiess I absolutely agree with your minimalistic selection. Regarding the series resistance you later recommended it in the video - but then in your next video you complain over the burnt-up potentiometers which seems to indicate that you yourself are not using them... And you didn't show them in your connection diagrams...
In the next video, the potentiometer acts as this resistor in my opinion. The potentiometer only was destroyed because I destroyed the FET.
@@AndreasSpiess yes, absolutely, it was only destroyed, because the FET failed, and with the additional series resistance between Gate and potentiometer wiper the potentiometer (or the Arduino) would be protected from this destructive power. In normal operation the serial resistance will slightly slow down the switching speed with a time constant of R times Cgate
Great advice as always. In video 290 you showed your transistor tester - very handy to see what that device is. I still use mine for measuring the beta of NPNs - but I am older than you! Afraid of high voltages? As an ex RF engineer, I find rf burns far nastier!
You are right about RF burns. But such strong RF sources are rare in my household ;-)
Great video :) when first messing with mosfet, I wish I had it... I managed to figure out what I needed, but it feels so much... safer? when someone shows the way
Fortunately they are not too expensive and quite forgiving....
Very useful video, thank you so much for creating!
You are welcome!
Swiss maybe understated but their humour are not. Excellent tutorials and valuable advice. Thank-you!
Glad you like the content!
I'd reccomend SO8 mosfets. They are able to have low resistances for a fraction of cost of to-220.
Also, once I bought AO3400A mosfets on Ali, which supposed to have 25-50 mOhm Rds(on). I checked their resistance and it was 5 freaking ohms...
Thanks for the tip on SO8. It was not on my "radar" so far... After a few comments about fake parts I decided to dig a little into it...
Awesome as always. Thank you..
You are welcome!
Thanks,always useful to refresh ones knowledge.
You are welcome!
Nice explanation
Thank you!
You really have to add the darlington transistor to a survival kit to my opinion, I use the ULN2003A chip for all my Raspberry Pi and Arduino projects because with these I don't have to think about adding a current limiting resistor on the input of the chip, it's already built-in. There are also flyback diodes built-in so with the same chip I can drive inductive loads like a relais without any problem.
And when I need to switch for example a power LED I can simply tie some inputs and output pins together, I can go up to 50 volt maximum which is more than enough for almost any project.
I think that when you only have the ULN2003A chip which is a 7 channel darlington pair you'll have a more than enough capable survival kit so this is the only thing you really need to my opinion.
It is a good chip, you are right. But often an overkill. And it’s current capability is also quite limited if I remember right.
@@AndreasSpiess The collector current for a single output is 500mA so it's capable enough. I looked it up in the datasheet it says that in some cases you can go up to 2.5Amp.
Great video, very easy to digest :)
Thank you!
@@AndreasSpiess I know it's an electronics IoT maker channel; but the pacing the clips is really good; the explanations follow a logical progression with strong emphasis on understanding - I'm really curious how you plan out scripts for your videos; and most importantly the summaries; a nice wrap to reinforce learning :)
I think BJT still have a place in the hobbiest's world. A power bjt is typically going to be cheaper than a similar power fet with a low-enough Vgs to be easily implemented without driver and also much more robust than FETs from an ESD perspective, you'd have to be trying pretty hard to destroy a good old 2n2222 NPN but a 2n7002 N-Fet is fairly readily killed. And while you don't go into linear, driving LEDs is a classic case where a BJT is useful for it's relatively simple means to select an output current, good enough for an LED, without needing any feedback or additional current limiting, just take the Hfe and calculate the base current, close enough job done. Anyway, at least a baggie of 2n2222 and a few BD139 should be in every parts draw if you ask me.
You are right. This is why I included them in hte video. But still, in the smallest survival kit I probably would place FETs...
Fantastic vid, cheers!.....Oh, I would pop a few 2N2222A in my kit...just for old times sake.
Then you should add a 2N3055, too...
@@AndreasSpiess Hahah! yes I have some..quite beefy I used them with car ignition coils to make big sparks when I was younger...I will pop one in!
Could you please do similar videos (need to have in a lab kit) for other components?
I am not sure. This channels usually is not for beginners. You should find lots of stuff about passive parts already.
A good "beginner" channel that include several video on components is ua-cam.com/users/Afrotechmods
Quite a useful video. Practical. Thanks.
You are welcome!
Highly educational. Thank you.
You are welcome!
Re: Anti-static measures. To be effective doesn't the anti-static mat have to be grounded? It is not enough to have an anti-static wrist-band and mat. Though this is not a video on ESD I suggest that it is misleading as stated.
You are right. Those ESD mats all have a connector for ground
I know the pick and place machines produce a lot of wastage (they cut a good size of before feeding). I've wondered whether the 'fake' ones could be recovered components (they have a sink to catch the trimmed tape ), or excess sent by customers who are having boards assembled.
I would not call your examples "fakes" because they seem to be genuine parts and they should work ok. It is well possible that they try to sell excess material via ebay or AliExpress. Which is a good idea, I think.
20:47 I was wondering if the push button could go between the PNPs gate and ground in this schematic... wouldn't that be better, for example if you're switching a load parallel to the µC ? but its a really nice idea to do it this way... minimal parts.
Your proposal would work, too. It was easy to explain in the video.
As always Andreas, you manage to pull it off. I really didn't need to see a video about transistors I thought, but you are entertaining, and as always I picked up some useful info. But I have one question, the girls that you go out with, they newer ask where the transistors come from, in my experience girls are really focused on where especially the capacitors and transistors come from :-)
I tried to give the video a slightly different twist because there are enough videos out which explain how they work.
BTW: I did not say they did not ask for. They just were happy with the answer ;-) This citation is from the famous UA-camr AvE
@@AndreasSpiess Thanks for taking the time to answer, keep up the good work. Sunday morning newspaper, not any more, now it Sunday morning and new video from the brilliant guy with the Swiss accent.
great video, my transistor survival kit consists of 2n2222 and 2n7000. Those seem to be the two I use the most.
Thank you for sharing your "kit". If you have my age ( according to your UA-cam name) then you probably also were "socialized" with BJTs. But those FETs are really amazing!
Such a useful video, that I must watch again. An incredible amount of material in your videos - a true professional! In the early 1960s when the latest thing was a germanium transistor in a metal case, we used to buy them in bulk and then have a group of us testing them to find the good ones. Maybe you could do the same? How good is your wife with a transistor tester? Thanks!
As I mentioned, last week I built a transistor curve tracer. This was part of the motivation for this video.
Comments about fake parts on AliExpress triggered now my next project: Test parts in my bin for specifications. We will see how far I get...
i also love to keep different types of transistors. don't have as many as you have though.
but i even went beyond the chinese sellers and ordered some germaniums from german sellers just to get hold of the obsoletes, and use them in audio applications. 😀
For audio applications you need much more stuff. This is why I had to exclude that topic completely for that video.
@@AndreasSpiess yup !
Hi Andreas, great video as usual. Thanks! One small remark: @8:56 you show a diagram without the base resistor, I hope your viewers will not try it like that, earlier in the video you already nicely explained and showed us why :-).
This was done because I showed what happens if you do that.
AliExpress sellers sometimes buy defective parts, which did not pass the manufacturer checks. I had some IRLML6402, which always passed current and some MPU6050 with one axis always showing maximum acceleration. To avoid faulty parts you should look at the item's photo and the description. There must be a photo of the component you looking for and not a generic picture of some random component, and at least type of the component must be written in the description. If it is so, it is 90% not defective or fake.
Thank you for the tips. I also test the more expensive parts when they arrive and start a dispute if they are not ok.
VERY Helpful/Educational , THANKS !
You are welcome!
Awesome video. I followed it closely. I have that transistor kit also. lolz
The "unnecessary" one? ;-)
@@AndreasSpiess Yes. lolz I thought it would come in handy. I like to play and make things. I do silly things like make logic gates out of them or use them in small projects. I guess it really depends on what you are doing.
Well I now know how to connect an esp to super led. ;)
Great video as always.
In my experience of buying MOSFETs on AliExpress N-Channel ones seem to be ok. Cheap P-Channel ones are almost invariably fake. Genuine P-Channel ones seem to be 3-5 times the price of N-Channel ones.
Many common parts seem to be okay, or at least usable. JFETs are another one to avoid; every JFET I got from AliExpress was fake.
After all the discussions in the comments I will make a video where I test my FETs to see, how many are faked. No fancy JFETs, just regular MOSFETS used in this video. The fancier the bigger the risk, I think...
Do any of the transistors in the survival kit need a heat dissipation clamp when soldering? The NPN/PNP transistors I first used decades ago required a clamp to dissipate heat to prevent damage. To be honest, I have not done a lot of projects.
I do not think so. At least I never use something like that.
No BJTs in the survival kit even though you said FETs are sensitive to small charges, therefore dependant of ESD equipmenet. Isnt it a good idea to also have some BJTs which will be useable even if you dont have ESD at hand?
Your choice. I showed my criteria. You can add others if you want. BJTs are ok. I work with FETs.
@@AndreasSpiess Thanks for the reply!
Mostly I prefer to use BJTs:
2n2222a
BC547
4n28
TIP31, 41c
Thank you for your feedback!
This is not a super easy suject for me, I love this video as a reference!
Hi Andreas, really great. Could you please post a recommendation for an ESD mat/kit? Or is it maybe a subject for a short video? Thanks and have a save trip!
I bought mine from surplus on Ebay. So I do not know a source.
My survival kit:
- 2N7000 - N-MOSFET, great for digital stuff
- BC547 - NPN BJT - The Swiss Army Knife of transistors
- BC558 - PNP BJT, complement to the BC547
- PN2222A - NPN BJT - If I need to handle a little more current, this is a good choice.
SMD is evil thus not part of the survival kit. Sometimes necessary evil, but not something I stock.
Missing from my survival kit is a good TO-92 P-MOSFET. It seems there exists no good complement to the 2N7000, you either have to go SMD or use power mosfets. Therefore in Arduino projects, I often resort to the BC558 BJT. It costs a resistor to protect the base, but going SMD or power mosfet is less elegant than using a resistor.
Thank you. I see you are "old school" ;-)
Don't forget the dynamic switching losses on Mosfets and BJTs while moving through the analog Path of the channel
I think I mentioned this fact in the video. Maybe not clear enough, though.
Hello awesome videos as always... Been wondering if you have any videos on home/office security using arduino or raspberry pie or esp chips?
Nothing specific. I covered some useful parts only
Thanks for your great video.
You are welcome!
Which mosfets would you recommend for a sot89 package? These are just a little easier to solder.
I do not have such FETs :-(
Andreas, could you provide an alternative to the IRF3708? I looked it up at Mouser and it seems to be EOL and has long delivery times. Thanks for your videos, they really help me realising my projects :)
FQP30N06L should also work
@@AndreasSpiess Dankeschön! Grüße aus Deutschland!
Is it possible that you use the Depletion MOSFET symbol at some places? The most common symbol for NMOS and PMOS use a discontinuous line for the chanel to add emphasis that there is NO current passing through when Vgs = 0. The LTspice diagrams are ok in that aspect, but the photocopies seem wrong: using a continuous line for the chanel, that would indicate a Depleted mode MOSFET ( a DMOS ) allowing the current to pass through when Vgs = 0 (which makes them useful for current limiting montage, as example).
I used the standard symbols of frizzing. I do not care too much about them. Too complicated for me if I look at the variants shown on one of my slides.
Hello, Could you make a video like this for OPAMP? when we should use which opamp? surely most of the viewers have questions like me. video for transistor selection was Excellent, Thanks
The EEVblog has some very good videos about Opamps.
@@AndreasSpiess you are right! but your video about transistors are Unique! your compare and how to select best transistor. about op-amp viewers need same for sure. help me to find if available any place. again thanks for your nice video. god bless u.
I harvest transistors and fets from old pcbs / power supplies :)
The TO-220 are easy because they are labled. The SMD are harder because they only have cryptic numbers printed on them.
@@AndreasSpiess yes that's correct
The arrows' tips should end on N-type material. For N-channel FETs this means the arrow should point toward the channel. For P-channel FETs it should point away.
I used the standard parts of frizzing.
I like to remember it this way: the arrow points from P to N to spell P-oi-N-t and the arrow is always on the emitter or source
@@AndreasSpiess Here are the worldwide IEEE standards:
ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7407262
Someone should point out "frizzing's" error. Since I am unfamiliar with them, I nominate you.
What about the AO3400 and AO3401 SMD MOSFETs. (Just have found them.)
God choice, too