Classic Circuits You Should Know: Latching Switch

Classic Circuits You Should Know: Latching Switch
Schematic: photos.app.goo.gl/wJBddeJKmws...
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[@benthere8051]

I like it. It's clean, simple, and glitch-free with no race conditions. The timing is generous. Other bistable latches I've seen are complicated and cluttered. The output structure of a 555 can drive a truck. It's a great task for a 555.

[@jj74qformerlyjailbreak3]

I ❤️ you threw the “KISS” Quote in there. 😂

[@0tt0z]

Great video! I love your coverage of classic circuits.

[@raym9691]

This was exactly what I was looking and asked for paul! Thank you good sir hope your 4th was relaxing and that your health is going as well as it can

[@westerngodzilla]

I just like that simple circuits. Thank You

[@incxxxx]

So what if do not understand how it works.

[@jeffreylangford962]

I set this circuit up as soon as I saw it. It sticks to the KISS principle ( Keep it simple stupid) Works perfectly, I have made transistor versions of on off latches and find they are susceptible to noise, especially when driving Mosfets. This circuit is a winner winner chicken dinner, well done. I will be using it all the time.😀👍

[@ttibor]

I like your videos man, you always show things that I have never thought I should know.

[@christiannielsen3863]

I like that you explain a little how the current flows although i would like som more of it to fully understand how it works. I think I am missing some basic knowledge, voltage dividing etc... have to search and read up on that. im very green in this.

[@jimtheedcguy4313]

This is perfect! Just what I'm looking for for my prototype!

[@idiotwithasolderingiron]

This will work nicely for the timer project I am working on for my washer. with a fancy push button start rather than a pull out knob.

[@SimpleElectronics]

I think I have a use for this! thanks!

[@bertspeggly4428]

Good clean circuit. I'll be using it!

[@georgestewart5879]

Another great video Paul, thanks.

[@MCsCreations]

Really interesting! Thanks! 😃

[@bigpickles]

Great video and narration. Subbed. Thanks, mate!

[@c1ph3rpunk]

This is exactly what I need, thx.

[@josephwarren849]

Great little circuit, I’ve built this up on my virtual workbench using multiSim, the simulation works great, Hi really love your little circuits thanks

[@willyrivero470]

I love it! Thanks. 👍👍

[@RapidBoss08]

You're a great guy. I recently got into electronics, and you are my go-to for information. Thank you.

[@learnelectronics]

Thanks for watching!

[@theflamethrower867]

This came out at the perfect time

[@mikeoliver3254]

One of my favorite uses of a 555. Great explanation. Hope you had a great 4th, and have a great weekend Paul.

[@incxxxx]

So what if it does not explain how it works at all .

[@philippeschjelderup9644]

Great tutorial as always. Been in Finland for 9 days and have serious abstinence of fiddling with electronics again.

[@incxxxx]

We have always in steady state 2.5V on pins 2&6, even when output is low! Only in transition states we have about 0 in one case and about 4V in the second and that is the reason that it works. Any way, thank you for the presentation of the interesting circuit.

[@albertbatfinder5240]

Mr Remmoz Thanks for that. I am admittedly at a low level with this stuff, but i had no idea exactly what was going on. Your comment helped. One problem (and there are many) is that most people don’t know why all this circuitry is necessary at all. It’s a light switch, or even simpler, it’s twisting two wires together. Have followed and built dozens of things with the help of Ben Eater and always learn lots. Here I learnt nada, zilch, nothing.

[@georgechambers3197]

A classic circuit I now know. 😀 Thanks Paul, I really am liking this series. Thanks for the video!

[@learnelectronics]

Welcome my friend! Thanks as always for being here.

[@incxxxx]

So what if it does not explain how it works at all .

[@KissAnalog]

Another great video in a cool series! I like the Kiss;)

[@michaelpadovani9566]

I have that fancy on-off LED switch haha i may use this circuit for that application thx for showing it off

[@tedbastwock3810]

This is fantastic, really loving this Classic Circuits series! Could this latching switch circuit be altered to change polarity? Im thinking in terms of a 12vdc motor and switching directions. Thanks for sharing with us, you are amazing!

[@oilybrakes]

Boy O Boy, whenever I see a 555 timer I am beginning to think whether doing the same thing would be cheaper and easier with an AtTinyA13. But then again... 555s are kinda neat too.

[@marcmicari7659]

Question will a capacitive switch work in this circuit? Thank you for your time, as always amazing videos!

[@saeedhassan7927]

Sweet thanks

[@weerobot]

Cool The Basics are essentail...

[@m.chandranmaruthan9421]

Good , i like it

[@Julian_Bester]

Please can you make a video of you making the circuit

[@tedbastwock3810]

Bro, I like your channel, Im learning from it, and you seem cool, so I will let you know .. a lot of links in your older vid descriptions are broken, since you are still getting views you could still be getting commission from active links. Thanks for sharing with us.

[@dmeemd7787]

I'm really surprised I had never seen a 555 used this way, I knew it was out there somewhere and I was trying to figure it out when I came across your video, in any case I'm stoked to have found it HERE, because you have an awesome channel that helps and teaches me a lot, especially if I'm stuck on something or I'm looking for inspiration and/or motivation in electronics or just in general :-) :-) hope all is well and, per usual, I will be checking for new content often - I was also glad I caught this particular account of mine (don't really use my other one much anymore) wasn't subscribed, Got that resolved fortunately :-):-)

[@captainpugwash4100]

I knew we hadn’t seen the last of the 555! Yippee!!!!

[@captainpugwash4100]

I think this is going to be my first PCB, a couple of these in my toolbox would be good addition. And the circuit will be relatively easy for a beginner! Won’t that momentary switch need a debounce capacitor?

[@ercost60]

It oscillates if you hold the switch continuously?

[@stewartrv]

Very nice. I'm curious for battery operated stuff what the quiescent current would be? Or should be use something else in that case. I know Dave (EEVblog #262) made something using a couple transistors - but I've got a bunch of 555's and so I'd love to know the pro's and con's of each.

[@tjtube263]

how many volts with these values?

[@whiskyweasal89]

Question- Is the voltage divider another IC, is it a componant? or it it just two separate but equal resisters going to different places?

[@danielrine3103]

Wonderful video, I have used the 555 in the bistable mode using 2 push button switches. I have built audio amplifiers using the LM386 and the TDA2822, and the 555 to turn on and off the amplifier. Trigger pin 2, amp on reset pin 4, amp off. This circuit will now let me use one push button switch to do the same thing. You have a great channel for DIY people such as me, thank you kindly for sharing this. Just one question, I see a 100K, a 10K, but can not make out the other resistor, is that 1K in the top loop? Have a great day, will continue to look for new videos....

[@killricheyrichNOW]

What happens if you just hold the button closed for a long duration

[@DustinWatts]

I should have known this! Luckily now I do ;)

[@shan_singh]

its turning on when button is pressed but not turning off when pressed again! can you help me with this please

[@frankowalker4662]

Thanks for this, I'll probably build loads of them! LOL.

[@firstlast8252]

I wired this exactly the way you are showing but it will not shut off??? I don't understand.

[@goodwill7643]

I think its useful for production where you want produce many quantities for minimum price. For hobby, usually if you come to an idea how you can improve your product ,then MCU like Attiny85 gives you much room for improvement without changing PCB layout. I had few project which were simple, but after some time I realized that I could create more functionality and with 555 timer you simply can't do it. However if you use MCU - just update firmware. Anyway, video is great, and it is good to know something more about 555 timers. Thank you.

[@kshamasinha2725]

Hey paul can you please explain how 2.5 V is appearing on cap ,is it the output voltage of pin 3 .

[@learnelectronics]

yes

[@drivejapan6293]

I love these videos but if you could have explained about how it works with the trigger and threshold reading the state of the capacitor and how it charges and discharged would have been much better. Knowing how it works is often just as important as it gives a basis to modify and make your own variations rather than just memorizing something. Still thumbs up and keep up the good work as an educator.

[@learnelectronics]

I have done numerous videos on the 555 timer. You can find them in basic electronics playlist.

[@drivejapan6293]

@@learnelectronics thanks for the reply. The sheer amount of info and uses for the 555 you go over makes it hard to locate the relevant information and then correlate it to this project. A lot of people watching this are beginners and wouldn't know what to look for or ask and how to find it and relate it to this. I wouldnt take much time to talk about how the trigger and threshold comparing the voltage of the capacitor to VCC. Each video as a self contained lesson is good for a lot of the less focused minds that exist in to days face paced world. You actually do that in a lot of your videos but thought it was missing here. Not recommending you go over every aspect of the 555 in every video with one just the relevant info. But I guess as the content creator you yourself have to draw the line somewhere and decide when and what is too much information.

[@la6mp]

I am teaching basic electronics to Thai Army soldiers , and the other day one student asked me to help him construct a "double function switch". After watching this video I realized that he meant a Latching Switch, so the I've sent him the link to your video. BTW, I really enjoyed you chatting about your young days in the Navy, I'd really like to hear about your getting your Dolphins and the following career... Cheers from John.

[@incxxxx]

So what if it does not explain how it works at all .

[@la6mp]

Mr Remmoz Paul explains both the wiring and how it works, and I follow up in class using different modes of the 555 timer.

[@incxxxx]

@@la6mp Exactly, He shows how it works but nothing explained. See on the oscilloscope signal from point 2and6 and you understand what I'm saying. But first you have remember in details how RS switch works.

[@incxxxx]

@@la6mp To be more clear. To put reset in RS of the 555 (pin 2and 6) you have to have the voltage jump above 3.33V (2/3 of 5V) - then output 3 is low in the 555 - LED is off) . And to put set in RS you have to jump below 1.67V for pins 2and6 (1/3 of 5V) - then output 3 is high, LED is on. So, I'm asking, when you have voltage at least 1.67V or 3.33V at pins 2and6 if they have about 2.5V as you measure by multimeter? Did Paul explained it? And this is the whole clue of the matter. Without explanation of this phenomenon the presentation is of very low value.

[@la6mp]

Mr Remmoz I am on holidays, when I return home I will follow your measirements and come back to you in a serious way. Thrse days my focus is on mountain hiking in Switzerland:-) See you!

[@andresdelhier3234]

hi can you check your schematic in the link, please check the cap you have it connected to c2, while in the video goes to Ground.

[@learnelectronics]

Corrected, thank you

[@user-be4yc2vr5c]

Can't tell you how valuable these vids are to not just me but the communities. Thank you Paul. Hope all is well and your health is good.

[@HelenaOfDetroit]

This looks amazing and I want to make it so badly. I've tried though, and it just doesn't work when I do it. I've literally watched this video over ten times. I've paused it, taken notes, looked at the schematic and even copied the exact layout on my board that he has. It just turns the LED on when I push the button but doesn't turn it off. Not sure how to fix the issue but I've spent the last two weeks trying to get a simple on/off 1 button latching switch to work for a project and I can't figure it out. None of the solutions using NPN BJTs, or MOSFETS, or even this 555 timer work whenever I try them. Obviously, I'm the problem, but I don't know what the problem is to fix it. :(

[@christiannielsen3863]

Oh, I also love the basic video being the newbie I am.

[@davidhead3768]

Kind of strange, the link to the schematic is empty but, the links to the store and PCB Way work just fine.

[@learnelectronics]

Thank you for your thinly veiled insult asshat.

[@LostInLeiden]

Are your schematics now offline? The link sends me to an empty album

[@RicardoPenders]

I have a problem with the 555 timer chip because I'm always pulling stuff from old used circuit boards and I never see the 555 chip so if you have the time could you please show a similar circuit but instead use only discrete components? Thanks, Ricardo Penders

[@mikepennington8088]

Try a J-K flip flop or the NAND gate equivalent hyperphysics.phy-astr.gsu.edu/hbase/Electronic/jkflipflop.html . Lacking all of those, you could build the gates out of transistors hyperphysics.phy-astr.gsu.edu/hbase/Electronic/nand.html and build the flip flop from those.

[@ianbertenshaw4350]

I recently used a 555 as a mosfet driver in an arduino project - why ? Because i have a heap of them and as they can source and sink current they can be used as drivers and saved me from having to use a logic level capable mosfet or a dedicated mosfet driver , every time i look for a simple circuit to do something the 555 seems to appear ! It would surely have to be the most versatile IC ever !

[@ed-jf3xh]

Don't forget the FET so you can switch something meaningful. Such as, oh I don't know, a radio. Yeah, use the flip-flop too. I think they'd like that.

[@pulesjet]

Handy beast. You can obtain a hand full of ne555 from BangGood for little to nothing right now.

[@eliasgeorge8534]

Hi Paul, your friendly Pathologist has a question about this circuit. Could it be or should it be considered as a hardware switch debouncer?

[@learnelectronics]

Hiya Doc, Not a debouncer. Just a flip-flop

[@davidhead3768]

the schematic link is an empty photo folder

[@jshellenberger7876]

Translate CC to Thai, please 🙏 Great teaching! # po 5

[@MalagasOnFire]

Again the flexibility of 555 timer is proven again.

[@albertbatfinder5240]

Sorry to say I didn’t think you explained anything at all! Maybe this is not my level. Trying to work my way down from a career of mainframe, mini, PC, embedded, and lately arduino programming, and this demo left me cold.

[@talideon]

This depends on earlier videos that deal with the 555. There's a playlist.

[@TheDefpom]

Just like me... simple and easy.... oh wait.

[@uvatham]

Why we need circuit ? Switch will do the same simple.

[@theflamethrower867]

shobin s there are other uses

[@incxxxx]

You did not explain how it works. You only pretended that you did it. Besides when you started "explaining" do not cover the scheme by breadboard.

[@learnelectronics]

Meldrop

[@mattflamenco]

Ta for that. Saves wading through endless trashy videos with no explanation and awful music.