NE555 tutorial: three useful circuits

[@WJCarpenter]

This is an amazingly clear explanation of how this popular circuit component works. Both the explanation and the accompanying video illustrations are especially friendly for anyone who wants to follow along. It moves pretty fast, but that's perfect for KZbin, where the viewer can pause and rewatch until the concepts are understood. Great job!

[@FriendlyWire]

Thank you so much, Bill! Yeah, I also realized the pacing is a bit fast, I will try to do it more slowly in future videos... I am still quite new at this, lots of things to learn! :) There is also the companion article at www.friendlywire.com/tutorials/ne555 with the written version of this tutorial, if you like. Thanks for your kind words, and have a great day!

[@rbiswas01]

One of the best electronics lectures on YT. Thank you.

[@FriendlyWire]

Thank you so much, glad you like the videos, Rudrajyoti!

[@mikoaj2323]

Very noob-friendly! I love that you've shown elements on schematics and on breadboard at the same time, explaining one by one what it's for. Oustanding visualisation makes it very easy to understand and not get confused. Definitely gonna watch more of your videos!

[@FriendlyWire]

Thank you so much, I am glad you like the video! :)

[@lvcifer-cloverfield]

Dude, Du bist einfach meine Rettung! Ich hab nen Labortermin in Praktische Elektronik verpasst und muss jetzt nen Bericht über Monoflop und Oszillator schreiben. Danke !!!

[@FriendlyWire]

Klasse, freut mich dass das Video hilft :-)

[@FriendlyWire]

Three things I forgot to mention/got wrong in the video (sorry about that): 1. It's a good idea to add a 100nF bypass capacitor between pins 1 (GND) and 8 (VDD) of the NE555. 2. Also add a 100uF capacitor parallel to the 9V battery. This way, if you are driving bigger loads (and not just one LED), there won't be so many ripples in the supply voltage. 3. 6:34 The blinking frequency is actually 1/(t_on+t_off), so it is closer to 3.3Hz in this case. If you look at 8:40 then you see there is no way the blinking frequency is 6.5Hz as I claim in the video. Let me know if you find more mistakes! Can we get it to 5? :D

[@Envai_Çesit]

Thank you for warnings. But this video is so value-added that I personaly didnt notice little details.

[@FriendlyWire]

@@Envai_Çesit Thank you, Erol, that is very kind of you. I am glad you find the video helpful. I think it also shows that there is always more to learn! :)

[@moobaa420]

At 15:01 you describe placing R3 to pin 1 of the NE555 but the schematic shows it in series with the LED connected to pin 3

[@moobaa420]

Actually I think I understand it now and although it is slightly different from the schematic it is just that you have swapped the placing of the resistor and the LED but that makes no difference.

[@FriendlyWire]

@@moobaa420 Good catch! And yes, you are right, it can be connected either way :)

[@MindFlareRetro]

Wow. Well done. One of the best (and easiest to understand) explanations of the NE555 (and its most common mode configurations) I have ever seen on YT, IMO. Very well explained and presented, as usual. Great work!!!

[@FriendlyWire]

Thank you so much, I am glad you enjoyed it!

[@kabandajamir9844]

The world's best teacher thanks sir nice explanation

[@FriendlyWire]

You're too kind, thank you so much!

[@hectormata449]

Definitely motivated me to try this entry level electronics project because the explanations and video were made very easy to understand and to follow. Thank you so much.

[@FriendlyWire]

Thank you so much, Hector, this means a lot. And I hope you'll enjoy playing around with these 555 timers! :)

[@Elikroon]

Thank you for the good video and telling it beginner friendly. also the articulation is very good to hear the words that are spoken Keep up the Good work 👌

[@FriendlyWire]

Thank you, I am glad you liked the video! :)

[@vinnybob792]

Amazing video. I would love to see more videos explaining more integrated circuits in the future

[@FriendlyWire]

Thank you so much! What kind of ICs are you interested in?

[@vinnybob792]

​@@FriendlyWireI am just getting into electronics and bought an assortment of IC's including the NE555. Some other IC's I was wondering about were operational amplifiers like the LM324 or NE5532. I really liked your video because it explains the internal circuit and provided multiple examples of things to do with them.

[@FriendlyWire]

@@vinnybob792 Thank you, I am so glad the video was helpful in that way. My main expertise are digital circuits (counters and things like that) but I may do a video on operational amplifiers in the future. Thank you, and have a great weekend! :)

[@_LIMH_]

Thanks!

[@FriendlyWire]

Much appreciated, thank you, Brandon!

[@IanJohnstonblog]

I discovered this channel from your conversation with Dave over on Twitter. He’s right. These are outstanding videos! Well done!!

[@FriendlyWire]

Thank you so much, Ian, I am happy you like them! Have a great day! Let me know if you have any comments on what I can improve, I am still somewhat new at this :)

[@IanJohnstonblog]

FriendlyWire literally nothing comes to mind. They’re superb. I really wish I had this type of teaching material when I was first learning. One thing that I see less experienced folks struggling with is how to properly use a multimeter. (How to measure the current of an LED for example) It would be great to have tutorials on the basic tools typically used to help debug and probe the circuits you’ve taught them how to build. Also, how to work with BJTs ... the humble 2N2222A is a useful little beast, especially when you need to drive a load from a TTL logic chip (or arduino module). Explaining the difference between source and sinking currents would be great too.

[@FriendlyWire]

​@@IanJohnstonblog Thank you, those are great ideas! When I started electronics as a kid I had an analog meter that was hard to read and only much later switched to a digital one, but only very recently I acquired a bench meter, and I am glad that I did... Debugging circuits is definitely a great idea, but it can get very complicated very quickly, so I will have to try and find a right combination that makes sense for beginners and does not require too many expensive tools. Thanks for the input, much appreciate! :)

[@nicolasleon1864]

This is truly great content, thanks for sharing! greetings from Argentina

[@FriendlyWire]

Thank you, Nicolas! Do you have anything else you want to learn? I am always eager to hear suggestions! Thanks again, and best wishes from Canada :)

[@onemorenight3470]

The best explanation on 555. You made it perfectly clear..👍👍👍

[@FriendlyWire]

Thank you so much, glad you find the video useful! :)

[@onemorenight3470]

@@FriendlyWire i heard about this channel from one my "guru"- (teacher) EKP CHINTHAKA , and he keenly recommend the channel. I must acknowledge him. Keep up good work 👍👍👍❤❤

[@FriendlyWire]

@@onemorenight3470 Thank you! :)

[@nabzero6528]

This video made me turn on again my interest in electronics. Thank you!

[@FriendlyWire]

That's fantastic, I am so glad to hear it! If you like this kind of stuff, and get it working with the NE555, check out my videos on the CD4017 decimal counter (and the CD4017 code lock), you might enjoy that, too :)

[@nabzero6528]

definitely!@@FriendlyWire Thank you!

[@FriendlyWire]

@@nabzero6528 Awesome! If something doesn't work, don't get discouraged, it's all pat of the journey. And I will do my best to help you out, just leave a comment under the videos :)

[@FriendlyWire]

@@nabzero6528 Of course, happy to help, and good luck! :)

[@yuriyzadorozhnyi3849]

Дяку друже за доступно і зрозуміло подану інформацію , 73!

[@FriendlyWire]

Happy to hear it, Yuriy! Моє задоволення :)

[@alanmoreno9074]

Just discovered your channel and I've got to say, this is some GREAT content!!!! Definitely inspiring :D

[@FriendlyWire]

Thank you so much, Alan, glad you like it! Have a great day! :)

[@alanmoreno9074]

@@FriendlyWire No Problem! and thanks! :) Also, I built the monostable circuit exactly like the video and it worked :D! but for some reason, I had to use a 220uF capacitor for the timer to last about 2.3 seconds.

[@alanmoreno9074]

Nvm lol i had a slow moment I grabbed a 22nF cap by mistake instead of 10 🤣🤣 the simplest mistakes man

[@FriendlyWire]

@@alanmoreno9074 Great work! And yes, these mistakes happen all the time, glad you figured it out and it all works as intended :-)

[@jerril42]

Excellent, fast paced, but not bad, especially considering there is a fantastic companion article. Thank you.

[@FriendlyWire]

Thanks so much! At what points am I going too fast? I would love to hear your feedback since I am still pretty new at this :)

[@jerril42]

@@FriendlyWire perhaps it would be more accurate to say it is concise, which is rare on KZbin. Fun to watch too.

[@FriendlyWire]

@@jerril42 Oh, thanks! I am very happy that you find it useful and entertaining :)

[@RinksRides]

Such a quality video. Thank you for omitting the stupid background music, makes it easier to follow.

[@FriendlyWire]

Thank you, Michael, glad you like it! :)

[@CharangoCalifornia]

At 15:09 you did not follow your own schematic and you switched the order of R3 and the LED. I suppose it still works because output on pin 3 will still switch from high to low. Shouldn't the resistor be on the end of the high output to prevent burning out the LED? Does it make any difference?

[@FriendlyWire]

Nice catch! It doesn't matter, you can build it both ways, it is exactly the same :)

[@Savan_Triveda]

I watched about ten 555 videos but I can^t manage to understand this beast.

[@FriendlyWire]

I know, it's a bit confusing to get started with it... Let me know if you have any questions, I will be happy to help. Also, there is a companion article to my video here: www.friendlywire.com/tutorials/ne555/

[@AG.34470]

Спасибо. Доступно всё объяснил и показал. Хоть и не по-русски.

[@FriendlyWire]

I am glad you liked the video! I don't speak Russian so I used a translator to read your comment :) Have a great day!

[@trynadyna9662]

Subscribed, this was an excellent video! Thank you for sharing your knowledge!

[@FriendlyWire]

Thank you so much, happy to have you, and I am glad you liked the video!

[@pq3929]

A very friendly tutorial, thanks!

[@FriendlyWire]

Thank you, I am glad you liked it! :)

[@joshuashan2165]

This video was simply amazing!!

[@FriendlyWire]

Thank you, Joshua, glad you like it! :)

[@Envai_Çesit]

Well done. I want to know the aim of C2 capacitor at 8:39. Thanks.

[@FriendlyWire]

Thank you, glad you like it! C2 is just there for stability, it is not part of the timing. You can probably omit C2, but it is recommended not to leave pin 5 floating.

[@75slaine]

Learned a lot, as always. Thanks for the great content 👍

[@FriendlyWire]

Thanks, that's fantastic!

[@styrishrodrigues]

Beautifully explained.. Loved it.. And subscribed too😉💖

[@FriendlyWire]

Thank you, glad you liked it!

[@florisliesker]

The part starting @1:30 confuses me. The output Q always seems to be equal to input S. Either I am missing something or something is missing from the explanation?

[@FriendlyWire]

Good question! The flip flop is a memory, so if both inputs are low, it remembers its previous state (if it was ON, it stays ON, if it was OFF, it stays OFF) . Hope that helps, and sorry for the confusion :)

[@TechTide00]

Really good video and explanations! Congrats!

[@FriendlyWire]

Thank you so much, glad you like the video! :)

[@lucapoliseno5291]

Awesome video once again

[@FriendlyWire]

Thank you so much, Luca, glad you liked it! :)

[@stereophotog]

Hi, excellent video and educational content, as well as useful examples. I want to test an old TI TLC555CP analog chip in oscillator mode. Since there is no practical or affordable tester for such a component, if I setup a model as shown in your video, and if it works, can I reasonably assume then that this TLC555CP works as designed? Also, if it is proved to be defective, can I replace it with a TI NE555P? Lastly, having detailed description of the video on your web site is an excellent idea, but a slower pace in your video would be very much appreciated. As a suggestion, you may want to split such a video into multiple parts if a slower pace would stretch it to over 20 minutes. Thanks again for putting such a detailed and interesting video, I know that this takes lots of time and efforts, let a lone good knowledge of the subject matter. keep it up!

[@FriendlyWire]

Thank you for that beautiful comment :) Several people have let me know that the pace in the NE555 video is too high, and it was one of my earlier videos, so I hope I have since taken that into account. Sometimes it's hard to realize these things by yourself, which is why I appreciate this comment a lot. I think that if you have build the astable oscillator circuit and it works as advertised then the chip should be OK. If you only test the bistable mode then you only know that its flip flop works, but you have no idea about the comparator module. Regarding the other variants of the chip: yes, they should work. The only difference is the operating voltage. Some chips (especially older ones) only work with exactly 5V DC, whereas newer CMOS-based designs accept generally 3-18V DC. So make sure to check the datasheet on that, just to be safe. Other than that, newer parts may support higher frequencies, but I think that may not be relevant in this case. Let me know if you have any other questions, thank you again for your comment, and have a great rest of the week!

[@patrickmulholland1840]

excellent as usual

[@FriendlyWire]

Thank you so much, Patrick!

[@dhanapallayya254]

10:21 how much capacitar and resistence use to 0.45 seconds and 0.35 seconds and 0.25 seconds Please reply bro

[@FriendlyWire]

Sure! Take the formula at 10:10, and fix C1 to be 47uF. Then choose R1 accordingly. To get your times you need R1=8.7kOhm (450ms), R1=6.8kOhm (350ms), R1=4.8kOhm (250ms). I would recommend a 4.7kOhm resistor and a 5kOhm potentiometer in series, then you can adjust between all these times. Hope it helps!

[@dhanapallayya254]

@@FriendlyWire thanks bro

[@dhanapallayya254]

@@FriendlyWire I am a new subscriber

[@FriendlyWire]

@@dhanapallayya254 Happy to help! When you build the circuit and take a photo, feel free to tag me on Twitter or Instagram via @FriendlyWire , I would love to see it :)

[@andrewromanov822]

Thank you for explanation!

[@FriendlyWire]

Thank you for your kind words, Andrew, I am glad you found the video useful! :)

[@3982100]

Very informative tutorial thanks 👍💐

[@FriendlyWire]

Thank you, Muhammed, means a lot! :)

[@s1nister688]

Just wish you uploaded more often, but anyway, amazing video.

[@FriendlyWire]

Thanks so much, it means a lot! These videos involve a lot of editing, and since I am doing this by myself it takes me a few weeks to finish one :)

[@ekp_chinthaka9845]

Wow . Today it became very clear.( Can you tell me about the op-amp if you can ? )

[@ekp_chinthaka9845]

Thank you, sir

[@FriendlyWire]

@@ekp_chinthaka9845 Thank you for your kind words! I hope to cover OP amps at some point, yes :)

[@DJCannon5]

I started jumping pins on a live 555 blinking light circuit and my board went dead, i thought I had fried the IC or something else and couldnt get the circuit to work, i started a new circuit and the chip and all parts worked fine. Is it possible I disrupted the chip without damaging it so it failed temporarily?

[@FriendlyWire]

Intermittent errors are always the hardest to spot... I am not sure. If is likely that perhaps the breadboard contacts were a bit loose and did not make proper contact. I have had the weirdest things happen on cheaper breadboards with unreliable continuity.

[@mapala3814]

Im beginner, i want use this ic but with 12v, what value of resistor should i use to replace 100k ohm and 10k ohm sir? Thanks in advance

[@FriendlyWire]

They can stay the same! They set the time constant of the charging/discharging of the capacitor, independently of the operating voltage :)

[@grandprime7397]

Loved it support from kerala india

[@FriendlyWire]

Thank you so much, have a great week! :-)

[@Syeda-Hadia]

Sir.. in astable mode the led cathode is connected with the wire which is already in 12 row?? Can u help me out

[@FriendlyWire]

You are talking about 8:19? Yes, the LED cathode is in row 12. The vertical black wire from row 12 to pin 1 of the NE555, and the horizontal black wire across to the right side (also row 12) are the "ground rail." See also at 8:34 how the 9V battery is connected. Hope it helps!

[@Syeda-Hadia]

@@FriendlyWire Such a legend you are.... Thank you so much..😊😊

[@FriendlyWire]

@@Syeda-Hadia Happy to help! :)

[@tamaghnadas8370]

Hello? I'm all new to these :( I just wanna know, instead of making my LED blink, can't I control it's brightness using a similar astable circuit and a potentiometer instead of R2?

[@FriendlyWire]

Hello, glad you found this video! :) Yes, you totally could, that's a great idea! This type of dimming is called "pulse width modulation" and R1 controls how long the LED is on, and R2 controls how long it is off (for more details see here: www.friendlywire.com/tutorials/ne555/#ch2 ). You just have to make the overall frequency of the circuit much higher so the blinking appears like a decreased brightness. Typical PWM frequencies are a few kilohertz (aka 1000 oscillations per second), so you could replace C1 from the 22uF to a 100nF to see what happens :) I have not done it in person, but it would be a cool project! :) Let me know if you have other questions or if I did not explain it well, I will do my best!

[@tamaghnadas8370]

@@FriendlyWire I din't expect such a quick response, tysm :) You really explained it very well and no one else explained the circuit schematic so well :D Also, I hope the PWM thing works for me!

[@FriendlyWire]

@@tamaghnadas8370 Happy to help, and thank you for stopping by! Definitely let me know how it works out :) One thing to keep in mind is that if you only vary R1 or R2 (i.e. change the on-time only or the off-time only) then the total PWM period will change. Perhaps it is better to think of R1 and R2 as the two halves of a potentiometer, so that R1+R2 is always a constant so you would have a fixed period PWM. Hope it makes sense! (If not let me know and I will try to explain it better!) If you have social media it would be so cool if you could send me a photo of your project @FriendlyWire , I would love to see it! :)

[@tamaghnadas8370]

@@FriendlyWire I do not think R1 and R2 can be seen as two halves of the potentiometer :( R1 has it's significance. However, R2 (the pot), I suppose, can serve in two ways- it's one half for charging C1 and the other half for discharging. Idk though if R1+R2 remains constant in such a connection, if I'm making sense at all-

[@FriendlyWire]

@@tamaghnadas8370 I am not sure if I understand. If you use the schematic at 5:09 you can see that C1 charges only through R1 and discharges only through R2. So my suggestion is this: remove R1 and R2. Then, connect the center tap of a potentiometer to pin 7 of the NE555 and to the anode of D1. One of the outer connections of the potentiometer goes to VDD, the other one goes to cathode of D2. Shouldn't that work? :)

[@RixtronixLAB]

Nice info, well done, thanks :)

[@FriendlyWire]

Thank you, glad you like it, and have a great weekend!

[@stevemuller7845]

An error has crept into the video. Frequency of the astable circuit is about 3,3Hz since fblink = 1 / ( ton + toff )

[@FriendlyWire]

You are right! Thanks! I included this remark in the pinned comment.

[@zuhaibchoudhary4635]

I want to create such a circuit That when I give 0 logic input come at trigger and instantly I will change it to logic high 1 after then. Now the ouput goes high when it receives 0 And the output remains high even when input becomes 1 . As no reset or threshold is pressed yet (i have tested it and its the way it works) . (Now remember at trigger pin input is still 1 high logic but its not reading it as it can trigger only one time and its already done as trigger received 0 initially.) Now i have an external circuit which is monitoring a voltage when this will become true I want the circuit to be reset and read that logic1 which is present ay trigger How can I achieve that?

[@FriendlyWire]

Thanks for the question! I am sorry but I don't really understand what kind of circuit you are looking for. Can you explain some more?

[@msg1956]

Excellent..!

[@FriendlyWire]

Thank you, I am glad you liked it!

[@TechTide00]

5:09 i tought he was goin to start singing fr 💀

[@FriendlyWire]

Haha what? :D

[@kabandajamir9844]

So nice thanks sir

[@FriendlyWire]

Glad you like it, thanks! :)

[@electronicphilia1687]

Thank you sir

[@FriendlyWire]

Glad you liked the video, happy to help!

[@rageshar5382]

Subscribed 👍

[@FriendlyWire]

Thanks Ragesh! :)

[@Mr_Motor]

nice content very impressive

[@FriendlyWire]

Thanks so much! Let me know if you have any questions :)

[@DRSElectronic]

Good ! thank

[@FriendlyWire]

Thanks, glad you like it!

[@alphahr]

Always keep a healthy quantity off 555 around, they are so useful

[@FriendlyWire]

Oh yes, absolutely! We only scratched the surface in this video, there is so many other things you can do! :)

[@ThijsKamphuis]

very nice yes

[@FriendlyWire]

Thank you, it means a lot :)

[@petersmith5199]

You said anyone can learn electronics...I'm sad to say, not me!....I can only dream this information could be understood by mere motals! Having said that, I think I could wire the breadboard and make this work.....ummmm, could be worth a try!

[@FriendlyWire]

We all have to start somewhere :-) If this is too advanced, start with a battery, a wire, a switch, and get it to work, and then take it from there. I truly believe that you can learn it, if you want to :)

[@ChandrashekarCN]

💖💖💖💖

[@FriendlyWire]

Glad you liked the video! :)

[@fransmurati2370]

Abbreviations is for writing and not for speaking

[@FriendlyWire]

And a sentence usually ends with a full stop. ;-) But kidding aside, what do you mean?

[@fransmurati2370]

@@FriendlyWire "Hi FriendlyWire, Thank you for pointing out my mistake. My concern is that when you use a lot of abbreviations in your presentation, it can be overwhelming for newbies like me who aren't familiar with them. While your presentation is great, the constant need to decipher abbreviations can distract from the main message and make it harder to understand. For those with a background in the subject, this might not be an issue, but for new hobbyists and students, it can be frustrating. I suggest using the full term initially and introducing the abbreviation later in the lesson. This would make your content more accessible to newbies and those for whom English is a second or third language. I'm not sure if your channel is primarily geared towards those already educated on the subject, but I wanted to offer this sincere criticism: the less frustrating and more helpful a channel is, the more likely viewers will stick around. If I encounter an unfamiliar term, I can always look it up, but it would be helpful if you explained key terminology at the beginning of your lectures, especially if you are also targeting newbies on the subject matter. Thanks for responding and perhaps considering my feedback!"

[@FriendlyWire]

@@fransmurati2370 Thank you for your feedback. Can you tell me at what point in the video I used a confusing abbreviation? Of course I always try to take feedback into account :)

[@hadibq]

you mean the 5k resistors are a "happy accident" 😅

[@FriendlyWire]

Bob Ross has spoken :D

[@ThijsKamphuis]

i used your schematic as a base and made my own from there! imgur.com/gallery/IztSifD

[@FriendlyWire]

Great work, thank you for sharing! (For some reason I just saw your comment just now...)

[@zetaconvex1987]

Nice tutorial, but please speak slower so that we can absorb things better.

[@FriendlyWire]

Thank you! I will try to speak more slowly. I was worried that if I speak too slowly people might get bored, apparently I overcompensated. When you click on settings, you can change the playback speed to 0.75, does that help at all? Thanks, and have a great day!

[@IanG-uf2fq]

Hey dude, slow your talking down so we can understand you better please.

[@FriendlyWire]

Ha, thanks Ian. In my earlier videos I was worried that if I talk too slow people would get bored. I am still figuring many things out, so I will keep it in mind for the future, thanks for sharing. On these older videos you can set the playback speed to x0.75 in the video options. Also I have a very detailed companion article on my website (www.friendlywire.com/tutorials/ne555/) where you can ready everything at your own pace. Thanks again, and happy holidays!

[@stephenyork7318]

This is too confusing. Ben Eater when building his 6502 computer clock is far clearer.

[@FriendlyWire]

Sorry it's been confusing! Have you checked out the companion article along with the video? It's at www.friendlywire.com/tutorials/ne555/ . I think I spoke a bit too fast in this video, as others have mentioned. Have a great day, and thanks for your input, I will try better next time :)

[@bogus_not_me]

You talk TOO fast! Trying to learn something unknown should NOT be explained at supersonic speeds! Let me know when you slow down and I might be back!

[@FriendlyWire]

Thanks for the feedback. Not sure if it helps, but when you click on video options you can set the playback speed to 75%.

[@neilaryaofficial]

Don't worry @FriendlyWire, i think he is dumb. Love ur video ❤

[@FriendlyWire]

@@neilaryaofficial Glad you like them, thank you. People have different communication styles :-)

[@ColossusEternum]

I like videos that pack a huge amount of information in as little time as possible. You can always rewatch if you miss something

[@FriendlyWire]

@@ColossusEternum Thanks, I am glad you like the style of the video :)