555 Timers - How A One Shot Timer Works - The Learning Circuit

Ғылым және технология

Karen has been digging into 555 timers for a bit now. In a previous video, she did an overview of the 3 different modes in which a 555 timer can be used. In this video, Karen goes into further detail about one of those modes: Monostable. Monostable mode is also known as a “one-shot” timer. In this mode, a single input signal of the 555 timer triggers it’s output to go high. The design of the rest of the external circuit will then cause the output to automatically reset back to low. Karen explains what’s happening inside the 555 to make this work, as well as showing a practical example of how to create this circuit on a breadboard: bit.ly/2xBffKz
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Пікірлер: 110

  • @gregorchard7881
    @gregorchard7881 Жыл бұрын

    I combined 2 of these circuits with variable resistors, activated by one switch to make a twin timer for making perfect boiled eggs and toast. It times the boiled egg and also tells me when to start cooking the toast so that the timing is perfect, once you set the resistors.

  • @bru2al1tyusa82
    @bru2al1tyusa824 жыл бұрын

    I love this series, it's easy to learn with this kind of presentation.

  • @josefonseca9178
    @josefonseca91784 жыл бұрын

    Here's a good practical application: when i was learning the 555 timer in engineering, my professor challenged us to make a traffic light circuit with minimal components. Only the 555 timer was allowed, along with passive components. You can do it with just two 555 timers if some one wants to give it a shot. Awesome video Karen!

  • @alguti2000
    @alguti20002 ай бұрын

    I've used the 555 for quite a few projects. First one was to delay power on of a wind speed and windshear sensor monitor, that I built for my car. I needed the monitoring device to start several seconds after the car has started. In a second project, I used the 555 to build a circuit for strobe lights. Well, I used the 556, dual timer, IC, to drive two LED strobe lights. Even though I've used the 555 before, I can't say I fully understood how it worked...until I watched this video.

  • @abderezakabidi4510
    @abderezakabidi45106 ай бұрын

    I wish if I knew this series when I was in the university, she could explain electronic topics easily. Good job, thank you

  • @voice4voicelessKrzysiek
    @voice4voicelessKrzysiek3 жыл бұрын

    You did a fabulous job explaining how it works. Thank you for that. I don't think I have ever used 555 but this time I need a pulse width extender and this is a perfect application of this IC for this purpose. I like to use MOSFETs for all kinds of stuff but this solution is way more simple!

  • @sergefrechette8995
    @sergefrechette89952 жыл бұрын

    Hi, Karen just to let you know your presentations of the 555 are excellent and I love to show your presentations to my students, clear learning . I also use tinkercad where they explore the circuits and can see simulations and proof when they have difficulty with breadboard connectivity. Love your work . I've been teaching electricity modules for the last 14 years, after a long career of more than 41 years on the railroad as a electrical supervisor and now this ongoing career , it is fun to see young students go out and become electricians and technicians..😎great service you are doing for young aficionados of electronics.

  • @canlobin2240
    @canlobin22404 жыл бұрын

    I follow you all the time. It gives me a lot of knowledge and I like you the most in the world.

  • @emcgon
    @emcgon4 жыл бұрын

    Thanks for a really good, easy-to-follow step-by-step explanation.

  • @MaxImagination
    @MaxImagination Жыл бұрын

    Karen's presentation and teaching style makes learning electronics a whole lot easier. Rather than being left baffled with a mash of improperly delivered information like from many lessons on other channels, you deliver the needed info in an concise and understandable way. Love this series! Waiting to see more on The Learning Circuit!

  • @maciejmuller2784
    @maciejmuller2784 Жыл бұрын

    I've watched several videos about the 555, but only after yours I finally understood! Thank you - good job:) I serched for debouncing limit switches, so maybe this can be one of way to use 555:)

  • @Adhithya1002
    @Adhithya10022 жыл бұрын

    Wow I love to absorb so much knowledge with such ease. Thank you internet and thank you Karen.

  • @topquark22
    @topquark223 жыл бұрын

    This is the best explanation. It helped me to finish my project. Thank you.

  • @borishruskar5108
    @borishruskar51082 жыл бұрын

    Very nice and very usable. I am following this series.

  • @victorjbarker
    @victorjbarker Жыл бұрын

    great video and lesson. I'm brushing up on 555 after many decades...I'm using 555 timer in one shot mode and feeding it into a 74LS04 hex inverter to create synchronized differential logic pulses and sending into a motion controller as a homing reference pulse. The controller requires differential input but the machine I am retrofitting only has a single ended reference marker pulse. I use this pulse to trigger the 555 timer and hence create the differential signals.

  • @chaitanyadeshpande8362
    @chaitanyadeshpande83623 жыл бұрын

    Very very good explanation mam I have understood the working .. but I have seen lots of videos regarding the timer ic 555 I am unable to understood the working but after watching this video I understood the how the one shot timer works .. thank you mam ...Love from India...🇮🇳🇮🇳

  • @roymckenzie3566
    @roymckenzie35664 жыл бұрын

    My favorite little IC....use it to build many cool circuits back in the 90s....

  • @maker_karen1785
    @maker_karen17854 жыл бұрын

    Apparently I accidentally said astable TWICE at the beginning. Sorry about that, folks! Guess I was just having one of those days. This is a MONOstable, one-shot time.

  • @mystreteacher
    @mystreteacher Жыл бұрын

    Thanks for the series. The short burst (and timed burst) comes in handy in gaming applications with individuals with cognitive and/or physical disabilities. I have a student who can access several switches, but not a joystick. In first person games like Minecraft, he winds up spinning when he engages the camera mode to look around the world. It's sensory overload. However, by limiting the activation time of the switch regardless of how long he hangs on it he can do what he wants to do. Next, I'm working on seeing if I can just really suppress the speed of the camera movements. What makes it an even more interesting challenge is the switches are also used for walk mode where he doesn't have the spin issue.

  • @bchrisl1491
    @bchrisl1491 Жыл бұрын

    Hello Karen, I’m using the 555 to ring a doorbell when a motion sensor detects movement. I wanted to create a normal sounding “ding dong” on the ubiquitous NuTone door bell, even though the motion sensor stays high for many seconds after being tripped. Thanks for the demo. 👏

  • @paulmacgiollacaoine8619
    @paulmacgiollacaoine86194 жыл бұрын

    Great presentation.

  • @geoffwade8144
    @geoffwade81444 жыл бұрын

    Well done, very clear, thank you.

  • @adrianomoraes7738
    @adrianomoraes77384 жыл бұрын

    Amazing content!

  • @shram86
    @shram862 жыл бұрын

    Very concise. Thank you.

  • @sameergupta7609
    @sameergupta76093 жыл бұрын

    Very nice video & explanation, Thanks Madam

  • @stillsalty947
    @stillsalty9473 жыл бұрын

    nice video, got a quick question though. Can the timer turn of even when the button is still bein pressed? should be possible right, because the button doesnt mess with the C2 threshhold right?

  • @raimbowbow8337
    @raimbowbow83373 жыл бұрын

    4:30 Let's connect pin 6 to Vcc through a resistor, not ground.

  • @dennishall5659
    @dennishall56593 жыл бұрын

    Great job Karen.

  • @lakshminarayanan6940
    @lakshminarayanan69402 жыл бұрын

    most useful vedio in youtube for me .thanks

  • @krzysztofbaranowicz7735
    @krzysztofbaranowicz77354 жыл бұрын

    Hi Karen great job 🤗🤗🤗🤗

  • @Cewu
    @Cewu4 ай бұрын

    I am crying rn, where were you when I was studying for my first exam 😭😭

  • @bhanupratappatel364
    @bhanupratappatel3644 жыл бұрын

    Thanks for this series and its very usefull stuff i love you mem from India 🇮🇳

  • @Arcadespecialties
    @Arcadespecialties8 ай бұрын

    Thanks for this!! I have a question for you. I have been trying to figure this out for some time now. I have a few claw machines I rent for events. I bypassed the coin mechanism and pulled out the wires and connected them to a credit switch for free play. The problem is if someone holds down the credit switch too long the machine throws an error thinking there is a coin jam. I tried ordering a one shot LM 555 kit to adapt to the switch, hoping I could get a single pulse signal to the machine no matter how long someone presses the button. I hooked everything up and was hoping I would get the result I would like. Problem is I believe that the claw machine credit switch is actually just completing a ground circuit whereas the one shot LM 555 kit is intended to send a voltage pulse. I was wondering if you would think there would be a workaround for this? Thanks for your great videos.

  • @groundzero.
    @groundzero.4 жыл бұрын

    could use as door chime, motion alert, mailbox notifier, sump pump fail alarm, drive way alarm all sorts of uses. the button can be any sort of activating device and the led can be a light or buzzer or relay to trigger something else only limited by what you can think up.

  • @prhc
    @prhc2 жыл бұрын

    Fantastic, thank you

  • @metecaylak6200
    @metecaylak62003 жыл бұрын

    Hello Karen, You made a very nice video, congratulations. I have a question for you; trigger signal How do I make the output be 2ms whether it is 1ms or 10ms. Thank you.

  • @andri_ju
    @andri_ju4 жыл бұрын

    Nice video Thank you

  • @josephmazzeo9413
    @josephmazzeo94133 жыл бұрын

    One time I made a 555 circuit in mono mode to temporarily turn off a smoke detector while cooking so the smoke would not set it off for about 10 minutes....I wired a tiny switch under the cabinet using thin magnet wire to the trigger input. C=100uF, R= whatever was closest to 5.5 Mohms in my resistor cabinet. The circuit was p-p wired on a small perfboard and fit inside the cover. If I remember correctly I used the CMOS version of the chip for low power drain (7555). Worked great and was safer than pulling the battery out and forgetting to put it back in, and more convenient! Note: Try this at your own risk - I don't want you to violate any fire codes or cause safety issues!

  • @curiouscatlabincgetsworrie7755

    @curiouscatlabincgetsworrie7755

    Жыл бұрын

    haha! great thinking right there. I will keep that in mind, but I won't promise anything. great idea, though! :D

  • @johnbotris8187
    @johnbotris81873 жыл бұрын

    What happens when you hold the button? Will the led still turn off after a time? Basically what I want is to build a circuit that will create a single pulse on the rising edge of a button press that will go down even if the button is held. I believe a 555 timer would be the way to go about it but I don't know if this is the right approach... (I have little electronics experience)

  • @PMuis
    @PMuis4 жыл бұрын

    Great video. By coincidence I could have used it today, I had a 10 port powered USB hub I wanted to coorperate in a product. Problem was I had a momentary on/off switch and didn't go on automaticly when supplying power. Once incorporated in the product I couldn't reach the button and when the product was powered off there would be no power going to the USB Hub. I found out that shorting the button with a resistor did the trick but otherwise this would be the solution to simulate the buttonpress

  • @kennedygauger4680
    @kennedygauger4680 Жыл бұрын

    Most excellent video. I haven’t seen “The Learning Channel” for awhile. Are you no longer putting out videos?

  • @icegelofficial
    @icegelofficial3 жыл бұрын

    Thank you very much

  • @gamebent
    @gamebent4 жыл бұрын

    Thank you.

  • @mustafasaad2128
    @mustafasaad21283 жыл бұрын

    Very informative

  • @FindLiberty
    @FindLiberty4 жыл бұрын

    Very nice.

  • @NuwamanyaPetr
    @NuwamanyaPetrАй бұрын

    So excellent

  • @mrashad219
    @mrashad219 Жыл бұрын

    I'm wondering if you can do something similar with 74 series NOR gate as the sr latch and an OR gate as the comparators?

  • @mohsinm644
    @mohsinm6443 жыл бұрын

    I am using this for my spot welder through variable resister fron .25 sec to about 2.5 seconds.. Switch on MOT through a relay..

  • @jaimeriquelme6727
    @jaimeriquelme67273 жыл бұрын

    Hi there, Can you design a variable on and variable off timer with 2 pots for each actions, I mean the hi time changes with one pot and the off time with the other pot. I dont mean a timer with one pot to change the duty cycle, but two pots. It can be with 555 or arduino or whatever. Thanks a lot for your patience to teach.

  • @abanhidy
    @abanhidy3 жыл бұрын

    Hi! Are you really sure, if you release the button at Pin2 and the VCC reconnected to Pin2 again throug a resistor does not change the output? I build this circuit and after I release the button it switch back to low...

  • @Jim-mn7yq
    @Jim-mn7yq4 жыл бұрын

    I’m confused. Does this vid describe an a stable or mono stable mode?

  • @anasasim3856
    @anasasim3856 Жыл бұрын

    One application could be frequency division, an incoming clock trigger could be used instead of the button presses. Depending on the values of the capacitor and resistor, which could be arbitrarily selected, the pulse width could be worked out. This would lead to a new frequency, perhaps a division of the clock.

  • @limebulls
    @limebulls Жыл бұрын

    What happens if you leave your finger on the button? Does the timer start as well or does it only start if you release the button?

  • @EarlLeeBird
    @EarlLeeBird3 жыл бұрын

    @ element14 presents would this circuit still work if the trigger is continuously switched since the circuit is powered up? I would like to create a circuit that lights a LED for 5 seconds when VCC is switched on and then keep the LED off until VCC is switched off and back on.

  • @stspringer2003
    @stspringer2003 Жыл бұрын

    I was wondering if you could create a video explaining how to use a 555 timer with two MOSFETs to alternate two blinking 3 amp, 40-watt led's. Thanks

  • @brendanlindsaywebb4932
    @brendanlindsaywebb49323 жыл бұрын

    Thanks, Karen. You're showing me how a Dub Siren works ;)

  • @petrucioci07
    @petrucioci073 жыл бұрын

    I have a beacon with a 555 2 resistors and 2 capacitors. Im trying to get the led stays on about half second and off about 2 seconds. I've tried and changed some some resistors and capacitors around and i can't get inequality values. Only equal. Which i dont want equal values. I want half ON and 2 second OFF approximately.

  • @stephenbrown5999
    @stephenbrown59994 жыл бұрын

    It's good for debouncing.

  • @raimbowbow8337
    @raimbowbow83373 жыл бұрын

    6:50 The transistor is on (not open!) connecting the capacitor to ground through the discharge pin.

  • @tommy49er
    @tommy49er4 жыл бұрын

    Real world application off the top of my head. Door latch buzzer. Input would be an impulse like a dial tone from a phone system or a user press button. The impulse triggers the 555 which pulls high to buzz the door lock for 5 seconds. And at the button end you could have equally simple circuitry to form a latch to stop a user holding the button to override the one shot.

  • @WendyGameing
    @WendyGameing Жыл бұрын

    what happens if you keep holding the button? Will it turn off? I'm looking for a circuit like that since more than a week

  • @douglasbell3344
    @douglasbell33444 ай бұрын

    0:27 "Astable mode also known as a 'One-Shot' timer" Astable is Free Running Monostable is One-Shot (Otherwise) Great graphics and presentation

  • @paulotieno5245
    @paulotieno52453 жыл бұрын

    Thank for awesome information about 555 timer , but my questions about 555 timer is , how can I tests or know when is it bad using multimeter? Thank you for now.

  • @abanhidy

    @abanhidy

    3 жыл бұрын

    measure the value of the resistance between Pin1 and Pin8. There are 3 5 kOhm resistors. If the result is 15 kOhm, the 555 is mostly fine

  • @sahabaaz.
    @sahabaaz.3 жыл бұрын

    wt if i hold trigger push button for 5 second , will the timer works or the output stays on.

  • @anasasim3856
    @anasasim3856 Жыл бұрын

    An indicator system for an automobile could also be built, with the mechanical pull of the indicator leading to the connection of the 555 timers to the power supply. The R and C could be arbitrarily selected, such that R*C=1s. The output of the 555 timer could be passed through a buzzer and an LED.

  • @frollard
    @frollard4 жыл бұрын

    Great lesson Karen...but...what's a practical application for this circuit? /s Great description. I've used and abused 555's many times before but never dug deep into the operation; just blindly followed some diagram. This really helps understand what's going on.

  • @arathcazares1326

    @arathcazares1326

    3 жыл бұрын

    frollard it's a monostable circuit, not astable. 😂 Which is no stable state, but just a relaxation oscillator.

  • @frollard

    @frollard

    3 жыл бұрын

    @@arathcazares1326 Not sure if that reply was intended for me or if I missed something...I never mentioned mono or astable... so makes me think you were replying to someone else.

  • @arathcazares1326

    @arathcazares1326

    3 жыл бұрын

    frollard forget what I said because I thought you were confused with practical circuits, by simply use two resistors and a capacitor. Make it as astable, but I also realized that she meant "a stable", not "astable from the video.

  • @arathcazares1326

    @arathcazares1326

    3 жыл бұрын

    frollard It's not practical, but it's kind of is by involving oscillator.

  • @johankotze42
    @johankotze427 ай бұрын

    I would use it to give a regular impulse to a Focault pendulum. Instead of a button, magnet at the bottom of the bob would induce a voltage passed through a capacitor and the output woud momentarily power an electromagnet which would attract the magnet. That is the basic idea. A small PV cell would keep LiPo cell charged, which will power the cisrcuit continuously.

  • @petersiekmann3316
    @petersiekmann3316 Жыл бұрын

    At the 28 second point of this clip didn't you mean to say monostable mode rather than astable mode?

  • @leoocallaghan4106
    @leoocallaghan4106 Жыл бұрын

    Hi Karen. I like your training style. I watched your video "How 555 timers work - The Learning Circuit" and you show Comparator 1 connected to pin 8. In this video you show Comparator 2 connected to pin 8.... I watch a different channel explanation which shows Comparator 1 to pin 8. Which I now assume is the actual correct configuration. Sorry to say.... I am now confused by this video lesson as it now does not make sense, or am I just a stupido?

  • @MarkReedman
    @MarkReedman4 жыл бұрын

    Awesome reliable chip has been around since 1972

  • @kwissiekwissie
    @kwissiekwissie8 ай бұрын

    Help me please. You say Astable mode but the graphic says Monostable mode. Am I correct that it is Monostable mode,... not Astable mode?? I thought Astable was blinking output as long as it is triggered. And Monostable it will blink once for an amount of time and than waits for the next triggering...

  • @JRyan-hr1we
    @JRyan-hr1we2 жыл бұрын

    great video but what about pins 4 and 5

  • @CABohol
    @CABohol4 жыл бұрын

    Nice

  • @dvgelectrician1605
    @dvgelectrician16054 жыл бұрын

    I also want a 555 timer circuit with a push button, 1/2 second pulse out even push button press long time. Plz, thanx in advnce.

  • @dumanamrenov497
    @dumanamrenov4972 жыл бұрын

    Can you explain how multivibrator works?

  • @gtog2t659
    @gtog2t6594 жыл бұрын

    104 capacitor use between 8 and 6 pin for stable work

  • @antoniomanoel2873
    @antoniomanoel28733 жыл бұрын

    muito bom

  • @Electronzap
    @Electronzap4 жыл бұрын

    Oops, accidentally said astable mode at the beginning ;) but great video!

  • @maker_karen1785

    @maker_karen1785

    4 жыл бұрын

    [facepalm] How did I not notice that?! Lol. Nice catch.

  • @Electronzap

    @Electronzap

    4 жыл бұрын

    @@maker_karen1785 lol, I call something by the wrong name all the time. It's the most common mistake that I fail to realize I am making while filming.

  • @shashankrevaskar1446
    @shashankrevaskar14467 ай бұрын

    What type of flip flop is use in ic555

  • @plain_and_simple
    @plain_and_simple Жыл бұрын

    At the start of the video perhaps you meant to say monostable mode, not "astable mode"? Clarification is in order here. Thanks.

  • @markday3145
    @markday31454 жыл бұрын

    Should there be a (small) resistor between the capacitor and the discharge pin, to limit the amount of current flowing out of the capacitor and through the transistor at the end of the one-shot pulse?

  • @JoshuaPritt
    @JoshuaPritt4 жыл бұрын

    I'd use this to turn a motor for a specific period of time from a single click of a button. Like starting a trash compactor.

  • @almezamasw86
    @almezamasw864 жыл бұрын

    Good

  • @arnelcondino2634
    @arnelcondino26344 жыл бұрын

    Hi Karen I missed you

  • @francisxavier437
    @francisxavier4372 жыл бұрын

    I wish you were my teacher !

  • @azkid110
    @azkid1104 жыл бұрын

    I used a 555 timer like this to build a circuit board for a paintball gun

  • @soheilmohammadi5876
    @soheilmohammadi58762 жыл бұрын

    One application is to timing in automation circuits

  • @jimedgar6789
    @jimedgar67892 жыл бұрын

    Button debouncing !!!

  • @deltakid0
    @deltakid04 жыл бұрын

    2:19 That's an SR Latch, not a Flip-Flop.

  • @roymckenzie3566

    @roymckenzie3566

    4 жыл бұрын

    Fo real

  • @ryancastillo7240
    @ryancastillo72402 жыл бұрын

    What if push button is continioues ON

  • @familyplans3788
    @familyplans37884 жыл бұрын

    watchdog timer , great video

  • @GothGuy885
    @GothGuy8859 ай бұрын

    If you wanna make me flip Hit me with a micro chip I'll be a diode, cathode, electrode Overload, generator, oscillator Make a circuit with me - The Polecats

  • @khaledkkhaled211
    @khaledkkhaled2114 жыл бұрын

    👏👏👍💞👑😘😍🌷🌹

  • @mauricioarevalo3820
    @mauricioarevalo38204 жыл бұрын

    Door buzzer for security doors.🤪

  • @mightymagnum8811
    @mightymagnum88114 ай бұрын

    Mistake at 4:34

  • @jd52wtf
    @jd52wtf4 жыл бұрын

    VVV

  • @TBL_stevennelson
    @TBL_stevennelson4 жыл бұрын

    The description is to hard to understand and if its completely right it needs to be dumbed down.

  • @_meechpeach
    @_meechpeach4 жыл бұрын

    Is no one going to mention the fact she said astable twice at the beginning, before changing to monostable without comment?

  • @honeyko7422
    @honeyko74224 жыл бұрын

    Clear as mud!!!! Can you refill this and speak English please

  • @alirizvi5007
    @alirizvi50072 жыл бұрын

    one shot is mono stable not astable

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