Pull Up and Down Resistors for Floating Inputs- Simply Put

High-impedance microcontroller input pins require extra help to mitigate floating inputs. We must keep our circuits tidy!

[@lisandroiaffar4501]

This is not the most but the only so-comprehensive video I have seen on this subject. All of the doubts I had, specially dealing with wasted energy, have been answered. Thank you so much for this

[@caseynimmo4440]

There were three time that I just had to stop and think, "holy shit it makes since now, that is so simple why couldn't I think of that". Thank you so much for your help.

[@GamingKeenBeaner]

I never thought that one day I might seek circuit knowledge from a dwarven warrior, but here we are!.

[@sylvaind9086]

The most concise explanation of pull up/ down resistors I have ever seen! THANKS!

[@thekandyman300]

This is hands down the best explanation I've gotten for pull down/up resistors. You deserve more soooo many more views, but you just earned a sub :)

[@Icehso140]

"A fly farts in Nebrska"...finally I understand why my DIY robot wife acts crazy sometimes. Be right back...got some resistors to change out. LOL

[@understanding-why]

This channel is so underrated. You're doing a nice job man.

[@Ori_Zappa_Rocks]

I know right?

[@whitefields5595]

“A fly farts in Nebraska ...” 💕

[@danielrehak801]

Wow, finally I understood it. Thank you very much! Favorite quote: "and it"s on in your bag, and you get to school and your battery"s dead" Has a nice rhyme to it.

[@dalelehmann6425]

Ive been working to find a clear explanation of pull up//pull down resistors. Finally found it here. Thank you.

[@user-su5sq5ib3i]

This was the best explanation of pull up down resistors ever!

[@rickperez8975]

The fly farts in Nebraska joke always gets me

[@sleeplessrobot9398]

I have been trying to understand this topic from PDFs for so long, didn't get the clear definition unless I watched this video . Thank you

[@Mark-m9z4q]

I feel like I have just listened to one of the great orators of our time. I took electronics in the Navy during the 70s and I served aboard a nuclear powered attack submarine. Later, I was an instructor for a major defense contractor. Even so, I believe that your presentation of precision, accuracy, wit, and yes I dare say it, intensity supplied more relevant information in the shortest span of time than anything that I had ever witnessed. One of the most challenging schools the Navy has is its nuclear power program. Although I had never attended nuclear power school myself, I served with many that did and even saw Admiral Rickover, the father of the nuclear navy, once. In my opinion and considering that you would make it through nuclear power school, you would have fit right in as a nuclear reactor plant operator in submarines. Thank you and may God Bless.

[@reinasama904]

This is by far the best explanation I've came across for this problem. Thank you so much!

[@Soflotony]

Best tutorial on this topic I have ever heard. Thank you.

[@thebimbashi]

was looking for exactly this for months... thank you!!

[@davef21370]

Great explanation. The tale about hearing the radio station through the pipes reminds me of a similar one where someone could hear voices/music constantly, turns out they were picking up radio signals in a cracked filling.

[@t1d100]

Very helpful! Thank you. We still miss you, so much!

[@simonwoodland1916]

Thank you! Your explanation is amazing! I was struggling to understand how an open disconnected circuit could read any voltage. I look forward to watching your other videos 👍

[@shanejovanovic6073]

"but now a fly farts in nabraska" It's perfectly said.

[@parapos]

I'm reading/watching about pull up/down resistors over a week now, and I figured it out with this video. way to go man!!! you deserve so much more!! (watched it 3-4 times, English is not my first language btw.) I will watch all your videos ,I'm sure there is way more to learn, and more important ,to correctly understand why and how ! subscribed.

[@simplyput2796]

I'm so happy that's what you got out of my video. A huge part of why I'm doing this channel is to explain the things that others take for granted. So many times in school you're told to just memorize things, or use these weird analogies that let you get your work done but don't actually make you understand the topic. I think it's important to truly understand things, not just be able to recite and regurgitate them.

[@alchemy1]

@@simplyput2796 You can say that again.

[@kennethdavis4807]

After watching many videos on this subject, this video answered "all" the questions I had. Simply put. Thank you! I have subscribed also. :)

[@aideainlancaster8832]

That was such an easy way to comprehend the uses of pull/down resistors! Thanks!

[@ricardomardi]

Your videos are of the Gold Standard. You have a gift for conveying the idea behind the complexities of electronics and science. After watching many videos on the basics of pull up/down resistors yours was the most informative & easiest to comprehend. I'm profoundly grateful for your very video lessons. Excellent work! Thank you. A big hello from Buenos Aires Argentina.

[@reubenrobots6352]

Hey, just wanted to add another Thanks to the pile! I'm in my first year studying engineering & I struggle to get my head round a lot of these electronics concepts. These videos really help break it down and understand it.

[@trailranger6602]

Okay, this is an awesome explanation and has finally cleared all that up for me. Thank you!

[@inerlogic]

In the 80s and 90s we had a 50,000 watt radio station in town i could hear on my toaster.

[@isaacreaves9315]

This was a really good explanation. It's helping me figure out what I should do about my project.

[@Mohrenberg]

This video is great man! Good job. I'm gonna have to check out your other videos now.

[@YuzuRyougi]

the best video about high impedance input and pull up/down resistors

[@NicholasHumphriesNZ]

Brilliant explanation video! Learnt so much and loved the additional details around power usage and safety. Very practical tips

[@KW-ei3pi]

Awesome explanation. I think I am finally getting it! Thanks

[@viggipedia]

Love this channel! Hope you are doing well :)

[@DerIchBinDa]

Actually I know a similar story and I think it was from the UK, where a teapot was always playing the local radio station when put on the stove. On a low volume but hearable and there was a TV team recoding that teapot playing music. And I heard from here in Germany from a installation guy, that he was working at a house where you could hear a radio station at the rain water pipes running down on the side wall of the house. I think this might happen more often then we might think but the effect will vanish as we switch all radio from analog to digital.

[@kyleolson8977]

I really appreciate the content of this video, I just I wish I had found this a months ago when I first started serious screwing around with electronics, it would have saved a lot of time. As it is, this is a great video to send to someone else to understand the concepts. (In a way it's frustrating to see all this explained so well when I had to figure all this out myself. Seriously, I wrote this while not finishing the video and you keep adding things I had to slowly work out.) As a middle aged life-long computer programmer, I was frustrated when various logic circuits didn't do what I expected of them when working with switches. I almost gave up at certain points because I was frustrated that things weren't working how I believe they should. I guess I just didn't get this electronics thing. As a matter of fact, the exact model I had in my head was that of a light switch, open and closed. Much of the material on electronics does a poor job of explaining a floating pin and fail to mention pull down resistors. They go straight from current, volts, resistance, capacitors, voltage dividers then straight to logic. There's no power, it's zero volts, right? Like a light switch. The datasheets will just say something like a "high-impedance state". Ok, I'm totally ready to understand that means. That looked fine when I first started messing around and had a single throw switch attached to an LED. But when I expect inputs on a 7400 chip to act like 0v and the outputs of the chips do random things and change as I make seemingly unrelated moves. I was puzzled for a while until I saw a switch example with not well explained pull-down. The example didn't explain exactly what it was, it just assumed you knew, and the term wasn't even there. But it's presence allowed me to start searching until I got the name. Even after I got the idea that there was this pull down thing I found myself looking through the books and tutorials I had to get a better understanding and I couldn't find good discussions of pull up and pull down in those materials, I had to find other places. I think some of the simple tutorials don't want to explain this because of what you reach at about 12:45. In order to say more than "use a pull down/up" you need to figure out what the values of the resistors are. My most recent issue was figuring out what resistors I needed for some open collector 7400 chips. For the resistor values on the switches I had a couple of examples I was copying and getting away with, but that was no good here. I did eventually find a web page which explained how to calculate both the open collector resistors, but you do a better job explaining why these values matter than that page did. Heck, you even summarize everything well at the end. You've found the places where I was getting tripped up and placed it in one video, and I suspect a lot of other people could use the same thing. Excellent work.

[@DavidGauerRatfactor]

This is the explanation I needed. Thank you for this!

[@waxranger]

your fly fart joke killed it!

[@TimothySmithii]

I love your teaching style, as well as your attention to cutting out silence/streamlining run time. I think your brevity makes a much more watchable video, which is more likely to be watched and referenced by others. Many people, including myself, have a reluctance to share a video that does not streamline the content in some way. We all know that person that sends us hour long videos and we ignore them, so I try to avoid being "that" guy. Your style I'd be far more likely to share. You've got a real talent for this. You overcome several hurdles most content producers I see stumble upon when starting out. You just need better quality lighting, IMO. The good news is you can knock up a photo grade LED for shooting video for like $20, if you know how to solder. (I feel confident that wouldn't be an issue for you.) There are tons of build videos on YT for full spectrum photo, high CRI, LED light boxes. If you only do one thing, build a photo light. Find one that shows you a before and after show using a regular LED or overhead compared with a high CRI full spectrum LED and I bet it'll convince you. The light you are using now has a super cool color temp, that is washing out the color IMO. Plus the single light source is casting shadows all over your face. I understand you are not requesting my feedback, I am offering it in the hopes that it may benefit you in some way, as I appreciate the info you gave me. This is my attempt at reciprocation that I feel could be of benefit to you. The "could" part of that I will of course leave up to you, my friend. No offense intended on my part regardless. Keep up the great content my man, you have a great delivery. You've a real grasp on the subject matter, and perhaps more importantly, a very clear understanding of the experience of the beginner getting acquainted with it. I've heard this explained many times and wish I would have started with you brother. Would have made everything a whole lot easier on me. Cheers!

[@simplyput2796]

Yep, lighting has been the bane of my existence for some time, especially considering I'm dealing with using an apartment bedroom as a 'studio'. I've been trying to improve things over time, but it's difficult to do without a ton of research and a few thousand dollars, so I just take solace in the fact that it's free content, so I at least don't feel stressed over it and can continue to work on it as I go.

[@joeborovina4769]

outstanding ! going to have to watch it again thankyou.

[@rodgerrodger6298]

thank you SO much the was hands down the absolute best explanation for pull up/down resistors 10/10

[@ezzeldin101]

Man, your explanation is incredible !!! Thank u so much💞

[@ingowenzel6818]

thank you for this very well explained topic. i had so many unsolved questions regarding this special issue, but now everything is clear and crisp. so you helped me a lot. if i had you as my physics teacher in school, i would have studied physics instead of economics (.

[@VS-qs7fn]

This really helped me BIGTIME so thanx man.

[@PatrickPease]

That board brings back feltboard vibes and I'm here for it. So you cant buy pul-x resistors, your placement of any resistor causes of it to behave as a pull-up or pull-down

[@user-su5sq5ib3i]

Going back to the dmm, with a 1M or 10M input impedance is a perfect example. I did a microcontroller weather station project back in community college, and I was having a lot of issues with my temperature sensor input reading over a voltage divider the programming and math was correct however I temperatures fluctuated very badly. I never did figure it out other than the temperature sensor and resistor bridge I made was approaching the stiff voltage rating of the input of my microcontroller. Still not sure, I had to give that sensor back and going to try it over again with Arduino

[@khizarmohammed7666]

Great video!

[@terpy01]

Great video! I've been banging my head against a DC step up converter, trying to figure out why I have to ground the EN pin to shut it off (don't wanna do this, I want a closed circuit to turn it on, not off). Turns out, the board maker put in a pull up resistor & I'm hosed. But silver lining, I now understand pull up / down resistors. Thank you!

[@ronpayne4505]

Great video! Could you show us an actual IC spec sheet, so we could see how these values appear in the spec sheet. The nomenclature. Thanks!

[@schmorb]

Thanks for this video! I am wiring around ten switches to an arduino, which will turn on an led strip at different sections. The switches have leds in them, does that mean i need to use external pull down resistors, or could i still use the internal pull up resistor on the arduino? They all run on 5 volts

[@Savage-lx5yj]

Thanks, great explanation!

[@Tinkerspark]

I finally understand, thank you for this

[@Manu-lc4ob]

That was so helpful. Thanks a lot !

[@enriquemansillaromero2146]

Best explanation ever.

[@dvelez811]

Best explanation!!

[@FI-Schutzschalter]

Omggg I finally got it. Thank you so much

[@stevenrogersfineart4224]

Great info but those J cuts gave me an anxiety attack 😆 🤣 😂

[@mattsnow4116]

excellent video

[@eduardmart1237]

Does a pull up or a pull down resistor is constantly consuming power even if the switch is open (you not pressing a button)? Or the power goes only when you press the button? And powers consumption efforts are worth it only if you going to use this switch quite a lot?

[@jacquelineheisel7915]

This is just for me to remember to come back to 17:25

[@sahraouiwalid9144]

i wish you the best ! thank you so much.

[@Isabellaa-ms5dk]

Finally i get it. You're the best

[@doudi463]

big thanks

[@MrMhsn]

Great explanation!! Thanks a lot!

[@fjl05]

I remember when taking electronics many years ago and got to semiconductors, the example circuits had these pull up and down resisters. Yet they never mentioned why they where there. And up until that point, I tried to figure out everything mathematically, but there was no way to add them to the calculation. I was frustrated and confused because they made no sense.

[@inerlogic]

"Your transistor does not transist" needs to be on a t-shirt

[@sleeplessrobot9398]

3:48 I got so scared when I looked at the bottom right of the screen

[@POLMAZURKA]

it is better starting at 11:17..............

[@2mek8]

MATE, YOU ARE god

[@katakomn9465]

10:08 we know that the addition pull up resistor is so high that the voltage drop in that resistor is near the V input. BUT we measure the voltage AFTER the voltage drop. So what i think, we will measure not 5Vbut near 0 volt. Do you have any idea what's wrong with my thought ?

[@rickperez8975]

I was confused also but! Remember the IC has a resistance attached to it also so at the sensing point the voltage drop isn't really 0V, In the case of the pull up resistor we want it to be somewhere between 5 and 3.5 so we choose our resistor appropriately to ensure the voltage drop at that point is in that range. Think of it like a voltage divider circuit. Unless the IC has no Input resistor then the voltage drop at that point will be zero. Or like in the case when the switch is closed, most if not all of the current flows down through the switch because it is a short.

[@mikewilliams3103]

Great info, but oh my lord, you make me dizzy with so many editing cuts in your video, I can't watch any more.

[@bobweiram6321]

Did you utter a racial slur at around 12:05?