434 Transistors "Survival Kit" and Tutorial for Makers

[@AndreasSpiess]

I am still in my summer break. As last year I show some interesting videos from the past (as mentioned in the intro)

[@3rd_Millennium_Engineering]

Enjoy the break. :-)

[@jhoanrivero7885]

Enjoy your sommer

[@EsotericArctos]

I will agree FET's are likely the most functional of transistors in the lab, but there are definitely applications where BJT's would be the better choice. Thanks for a great comparison and educational video :)

[@AndreasSpiess]

I agree. But, as I said in the introduction: I focused on digital applications where MOSFTs are very strong.

[@pyrobeav2005]

My go-to for medium power microcontroller interfaces is the ULN2803 Darlington array IC. It has eight channels that can handle 50V and up to 500mA with 3.3V and 5V logic inputs. It has built-in input resistors and protection diodes on the outputs. I have a pile of DIP form factor ICs but they also make them in SOIC form, useful for prototyping that can be directly translated to a final design.

[@AndreasSpiess]

I agree. These are good if you need more then one or two low current outputs.

[@acestudioscouk-Ace-G0ACE]

As a non-techy, this was fascinating and I loved following the logical arguments used to finalise the choice. Thank-you.

[@AndreasSpiess]

You are welcome! Logic is universal ;-)

[@zyghom]

Invention of transistor was probably the biggest milestone in the electronics world - can we imagine today processors built on tubes? ;-) At 4:57 & 9:00 - this diagram has no ways to work without ... grounds connected ;-) Also: very simple but quite needed for ESP: programmer (if you don't use ESP modules but ESP boards for the project) - you still need 2x NPN for auto programming (without pressing BOOT or if you don't have it/don't want to have it) - it requires 2 BJTs - I am not sure they can be simply replaced by FETs. MOSFET transistors in serious projects are always driven by MOSFET drivers (specific ICs for this purpose) - controlling MOSFETs is not as trivial as one would think - especially when we talk PWM with high frequency - probably one more parameter should be considered while choosing the transistor type: Avalanche Energy

[@AndreasSpiess]

I agree that I forgot to connect GND. I think the two BJTs could be replaced by FETs. But BJTs probably are cheaper... You are right: MOSFET drivers are used in the applications you mentioned. But for most of Maker's usages, they are not needed, also because MCUs usually do not switch too fast nor do we switch heavy loads where the steepness of the edges are very important.

[@marklewus5468]

This was a great video as usual. I think it would’ve been helpful around 13 minutes in to note that there is indeed a connection between the gate and source of a N-MOSFET. It’s just that it behaves like a capacitor unlike a BJT where the base behaves like a diode, so MOSFETs do indeed require power to switch on and off. If you try to switch MOSFETS rapidly with a limited current source like an esp32 especially through a resistor, the FET can spend a lot of time in a partially on state, causing it dissipate much heat. If you have not used these before, this is what MOSFET drivers are for. They provide high current to rapidly switch the MOSFET on and off and should always be used in high frequency applications such as PWM into significant loads.

[@AndreasSpiess]

I agree that you have to charge the gate capacity before the FET switches. Unfortunately I always have to omit a lot of details for short videos :-(

[@tonysfun]

Again, number 1 video!!! You have squeezed lots of great and detail information into a short video. You saved me lots of time and endless research! You are full of great information! Also, I do have the RD6006 that is a great addition to anyone's lab, like yours. Thank you again Andreas!

[@AndreasSpiess]

You are welcome! My RD6066 is also the workhorse in the lab and is used nearly every day.

[@the78mole]

Hi Andreas, I would not render NPN and PNP totally useless. I often create small, switchable current sources by using them with an emitter resistor and an LED or two Diodes (as a voltage reference) between base and GND. With a red LED (1,6V), you can easily get the current drawn by the collector with approx. 1V/R. With 100R as an emitter resistor, you get a 10mA current source, perfect for driving and switching an LED with an unknown (e.g. 3...50V) supply voltage. This would be way more effort with a FET. For driving well defined low to medium currents I usually only use BJTs.

[@AnnaVannieuwenhuyse]

LEDs and pull ups and downs are what I love using bjt's for! They're so simple when made simple

[@AndreasSpiess]

I hope I did not say BJTs are useless. I focused on digital applications and there, for a "survival kit", I felt MOSFETs are the better choice.

[@the78mole]

@@AndreasSpiess Yes, you are right, for pure digital, simple applications. For interfacing to the outside world (e.g. S0-Impulse input), a BJT releases you mostly from ESD precautions and makes the design much simpler. But you are never released from calculations on the default transistor circuits (emitter, collector or base circuit). But there are enough tutorials out there and I think, your video covers what most users need to understand and what they need for practical MCU circuits.

[@GnuReligion]

My favorite NPN MOSFET is the IRLB3034 for being logic level, and having very low Rds(on). Must be careful to put some resistance in front of a FET gate, as capacitive bouncing can cause latchup or uneven switching.

[@AnnaVannieuwenhuyse]

I don't think NPN & PNP are correct terms for MOSFETs. Aren't they P-ch and N-ch?

[@Broken_Yugo]

@@AnnaVannieuwenhuyse correct, NPN/PNP refers, roughly, to the physical construction of BJTs. Field effect transistors (MOSFET/JFET) are built differently.

[@AndreasSpiess]

I agree: The IRLB3034 is a good choice as an n-channel MOSFET.

[@samsmith1580]

Another excellent video that gets right to the point. Thanks for posting

[@AndreasSpiess]

Glad it was helpful!

[@absurdengineering]

Cool thing about gate capacitance: it stabilizes op-amp based current sources that use a mosfet configured with negative feedback from the source terminal. An output-to-negative-input stabilizing capacitance is provided inherently by the mosfet. It may not be enough, but plenty of times it works. But don’t delete that capacitor footprint on the pcb. Leave it unpopulated. It may save your day later :)

[@AndreasSpiess]

It is always cool to use "parasitic" parts of a device. The bypass diode is also such an example...

[@GlennHamblin]

I have to stand up for the BJT. Not fancy or efficient but they can be had for less than 3 cents in relatively small volumes. 🙂

[@Broken_Yugo]

Last I checked the 2N3904 (or similar) is pretty widely the cheapest transistor you can buy, at least in through hole.

[@GlennHamblin]

@@Broken_Yugo Yup and the venerable 2N2222.

[@AndreasSpiess]

I am not against BJTs. But for a "digital survival kit" I voted for FETs.

[@matambale]

"Good enough for the girls I go out with" - wow I have not heard that expression since the mid 1970s! Hilarious and useful content Andreas, thank you.

[@NiHaoMike64]

Reference to AvE.

[@AndreasSpiess]

Glad you enjoyed it! And indeed I learned it from AvE

[@notquitecopacetic]

I almost spit out my coffee..."shit, we still have 20,000..." Good stuff.

[@AndreasSpiess]

Sorry for that ;-)

[@anispinner]

From my experience, the majority of fets on aliexpress aren't fake but most of them have substantially smaller crystal than the original one. So if it's rated to sustain 60A drain I'd look for a third or at most half of it (20-30A) until the burn out. That said one of the packs that I've got had one fet that essentially was a paired schottky diode with the transistors lavel.

[@AndreasSpiess]

I would call those "weak" parts fake. I am cautious with special parts and parts where the AliExpress price is much lower than the "real" price. Cheap Chinese manufactured parts usually are ok probably because faking them is too much work.

[@pjaj43]

I've used the RFP12N10L with Arduinos as a good logic level N-Channel: FET in TO-220 package. Readily available for about £1 each (10 pieces) from all the major suppliers, RS, Farnell, Mouser, Digi-Key etc.

[@AndreasSpiess]

Also a good choice!

[@AndreasDelleske]

"Try once to go to your boss without an alternative to discard" - haha - gold advice right here!

[@AndreasSpiess]

I am 65. Enough time to learn ;-)

[@digihz_data]

Great info about using right type for arduino /esp. Thanks Andreas.

[@AndreasSpiess]

You are welcome!

[@kostasa8895]

Thanks. Excellent summary

[@AndreasSpiess]

You are welcome!

[@thomash.3061]

Danke für die Mühe und Tipps.

[@AndreasSpiess]

Gern geschehen.

[@avejst]

Great video as always 👍 Thanks for sharing your expirence with all of us 👍 😀

[@AndreasSpiess]

My pleasure!

[@santoshbansode697]

Appreciated your work,,,, and thanks for recomend us that book,,,,, your contribution is really helpful for everyone,,,,,,,,,,,

[@AndreasSpiess]

It's my pleasure!

[@ChrisHalden007]

Nice reminder 👍 Thanks

[@AndreasSpiess]

My pleasure!

[@derekloudon8731]

Very useful refresher video, thank you.

[@AndreasSpiess]

Glad it was helpful!

[@der94alex]

Great video to expand upon or as starting point!

[@AndreasSpiess]

Glad you liked it!

[@planker]

Good things to think about. Most of the special Transistors I use are recovered from scrap boards I have chosen to use in the project. No guessing if its a fake, and the little tester will tell me Hfe and Fv drop. The 2N2222 for me is the most bought transistor in my inventory. I'm too new to have exotic Mosfets laying around, Amperage means fires, for now I'm keeping it to a 2S/3S systems. A 2n2222/2n2907 push pull mini amp sounds so much better than a Lm386 and the 2n2222 gives us 800ma to play with stuff using Arduino. But I live in Arizona, a tech from India will have the BC547, Somebody in New England has a grip of 2n3904's. Does Ikea make Transistors yet? I look forward to istalling the legs onto my transistors.

[@andymouse]

My favorite BJT as well !

[@AndreasSpiess]

Using recycled transistors is a good idea, particularly, as you describe, for exotic parts. They are often faked on Aliexpress and the shipping is expensive on Digikey for small orders...

[@pavelperina7629]

I would not say that BJTs are useless. I use them to invert signal for driving mosfet gate for example. Difference is that signal logic p-mosfet in TO92 package such LP0701 costs something like 2EUR and it's one of the few transistors with low vgs(th), although in my experience, transistors with typical vgs(th) of -2.4V can work with 3.3V logic. On the other hand, for 10-15EUR you can get 300 pieces of BJT from China which you showed and third of that price is the box.

[@AndreasSpiess]

I hope I did not say they are useless. They just were not needed for my minimalistic survival kit

[@Alacritous]

Tup tun dug dus is what they used to use define the most common needs for transistors and diodes. For the most common types that could be used in the most common situations.

[@AndreasSpiess]

I do not understand :-(

[@Alacritous]

@@AndreasSpiess KZbin keeps deleting this comment I don't know why. Search for "TUP TUN DUG DUS". It'll bring up a magazine article showing a collection of similar devices. It stands for Transistor Universal PNP, Transistor Universal NPN, Diode Universal Germanium, Diode Universal Silicon. When building projects, a large variety of devices can be substituted for each other, depending on what's available to the builder.

[@AndreasSpiess]

@@Alacritous Aha. Now I understand. It seems that they had similar problems already when much fewer parts existed... KZbin does not accept links anymore and deletes such comments 😞

[@lineways5477]

Can you make a video about how to control regular 5-12V old relays with both Arduino, ESP8266 and ESP32 and transistor thanks.

[@tamazerd]

Just replace the LED and its current limiting resistor shown in this video for the relay coil, and let the FET switch the 5 or 12V on or off?

[@churrerosandsons]

Study with many books, the best way to control transistors.

[@kek7778]

@@tamazerd You need to add a reverse biased diode to the relay coil in order to protect the FET against voltage spikes when turning off the relay!

[@tamazerd]

@@kek7778 Yes totally forgot about that!

[@AndreasSpiess]

@Line Ways: I hope you got the answer in the above comments: Use an n-channel FET and the protection diode and you are done. Maybe you want to add a 10k resistor between gate and ground to make sure the FET is switched off if the pin is on "input"

[@kevinadam9944]

"Good enough for the girls I go out with." Haha. Love it.🤪

[@AndreasSpiess]

:-)

[@wvdmln]

Veeeery interesting! Thanks👍

[@AndreasSpiess]

My pleasure!

[@smartassist9700]

Sir Andreas, I need to mount Arduino uno(s) but run sensors wiring up to 25 feet distance. What gauge (size) wire should I buy? Hopefully, I will buy multiple items for my “first” stock inventory to build things. USA we use 120volt AC and 230volt AC (for energy hungry devices). Do I need different transistors or other items for “AC” POWER SOURCE? FROM WHAT YOU LIST IN THIS VIDEO. WHAT SOURCE IS BEST FOR ALL ITEMS?

[@AndreasSpiess]

1. Check the power consumption of your sensor. If it is only a few mA the gauge does not matter if it is 24 or bigger. But you could get problems with interferences.

[@ConsertandoTudo]

for small signal transistors I just bought a box from China. Even if they are conterfake (doubt) you can still measure the gain, and debug any problem a transistor out of spec is introducing in the circuit. For "power" bjt I do have my jelly beans components, TO−204AA I do use MJ15003G and it complementary pair MJ15004G. It is good according to the Data Sheet up to 2MHZ. I only use it to audio. Back in the day I used 2n3055, but at local stores all of they are fake. Not worth at all. TO-3 I use 2SC5200 and 2sa1943. Mosfets usually IRF510. All of those I use out spec max frequency, (Except the mj15***) Also BJT does a great job in linear power supply. And small signal transistors do work way out the specific frequency in the data sheet. Worth to have in my opinion

[@AndreasSpiess]

Thank you for sharing your experience!

[@bradleyr4451]

so I sorted out 1000s of my parts, ics etc while my internet was OFF, no modem available anywhere; find and gather all these chips, components, project bags of parts, etc into one box, neat and organized. planned to be making circuits today. But the dogs were bored, must have seen me using all those parts for hours and being all over that box and they wanted to join in and play too. All done. On to other things and its night time. Then hear some very odd plastic crackling noise? find the box on the ground, ALL the parts strewn across 2 rooms. Bag of 700 LED's ripped open, LEDs across 2 rooms. Plastic box with a bunch of various 74LS-xx chips? (no 74HC static sensitive junk) The dogs didnt know, they didnt have chew toys, while it upset me I had to blame myself for leaving it at ground level, with no lid. if only I could make a go fundme account to raise money for electronic component purchases

[@AndreasSpiess]

Bad luck! I do not have dogs and our cat (fortunately?) is already old. She just sleeps in front of me...

[@bradleyr4451]

@@AndreasSpiess Cats like that are nice, they dont mind hearing you explain things. One I had? Seemed to help her sleep. And I hope to put in shelves mounted on the wall up at the ceiling. With a lock on them.

[@ddavid2]

Quite interesting!!

[@AndreasSpiess]

Glad you think so!

[@roberthousedorfii1743]

I would love to see a BOM for the distributors. This would be QUITE useful.

[@AndreasSpiess]

I do not understand :-(

[@roberthousedorfii1743]

@@AndreasSpiess some of the electronics houses let you create a bill of materials. BOM Like digikey, maybe mouser. I believe you can share that. Then, I am able to order all those parts with a few clicks.

[@youpattube1]

I am confused. You showed that PNP transistors won't work with a supply voltage greater than 6 volts. But in the summary, you say the PNP is for the high side. What does the "high side" mean ?

[@AndreasSpiess]

What I did not mention is that you need a second transistor if you want to switch voltages more than 5-6 volts with PNP transistors and an Arduino. I only covered the very basic stuff.

[@igrewold]

Thanks man

[@AndreasSpiess]

You're welcome!

[@FindLiberty]

PERFECT

[@AndreasSpiess]

Thank you!

[@rohitkhanna4487]

the BJT needs a base resistor which is must for base current limiting....

[@AndreasSpiess]

You are right.

[@MichaelKingsfordGray]

I prefer thermionic valves. (Tubes).

[@AndreasSpiess]

That is ok with me...

[@berndeckenfels]

Warning, most of those FETs with metal tabs they are connected to the drain

[@AndreasSpiess]

As always: RTFM ;-)

[@2pi628]

👍

[@AndreasSpiess]

:-)

[@armanhossain2491]

can anyone tell me what will be best alternative of JFET (2N3819/J310 etc).

[@AndreasSpiess]

I do not know :-(

[@nezbrun872]

FWIW, Mouser still stock 2N3819, but they're not particularly cheap. I found that trying to source off eBay was a waste of time, the devices often turned out to be fakes, NPN transistors.

[@lrlemos0]

Great!!!!

[@AndreasSpiess]

Thank you!

[@neodimium]

5:40 I can smell that

[@AndreasSpiess]

You do not need if you pay attention ;-)

[@paulcohen1555]

I strongly believe that most of AliExpress components are fake. That's why they started removing the manufacturer LOGO from pictures and components. It is very difficult to get genuine components unless you buy from a big chinese distributor like LCSC.

[@AndreasSpiess]

I am not so sure. Standard cheap components usually are ok because faking does not create a lot of value. The bigger the difference between the "real" price and the price of the AliExpress offer, the bigger the chance for a fake. Particularly for parts that are not available elsewhere. I agree: LCSC is a good alternative.

[@iceberg789]

BC547 for all small signal small power purposes. thats why need to buy them in dozens. and many cheap aliexpress parts are not fakes, they are just factory rejects who fail to meet the specs. 🤣

[@AndreasSpiess]

I even think that the cheap parts on AliExpress are standard parts. I do not assume there are so many rejects in today's manufacturing process.

[@speckblue]

My gut twitches every time I see that creepy pointing hand. Otherwise thanks for the excellent video! :)

[@AndreasSpiess]

:-))

[@tailerbrown6825]

27:04 lol what ?

[@AndreasSpiess]

A quotation from AvE...

[@tenminutetokyo2643]

DOOD!

[@igrewold]

Man if you are stuck just get a trasistor kit like elenco or from futurelec ( transistor value pack, this is only bjt assortment )

[@AndreasSpiess]

:-)