how NE555 works in astable mode ?

Asked by bonhome 9 years ago | last reply 9 years ago


Which transistor for ne555 output?

I have a simple circuit based on an ne555, the power supply is 15 volt provided by a robust ac adapter. On the pin 3 of the ne555 i need a max current of 4000mA. I was thinking to use a BD439 transistor, would be ok? And about the base resistor? Would be ok a 100k resistor or i need a different value? thanks a lot.

Asked by akopelumenuscu 3 years ago | last reply 3 years ago


NE555+LED Contest (inofficial)

Hey Electronic Nerds! I added a small contest to my contribution for the Instructables Advent Calendar 2011. Go for it and make your own NE555+LED-Circuit OR an LED-circuit with other components. Share your circuit in the comments of the I'ble to win a 1-year Pro-Membership. Only restriction: It has to fit on a mini breadboard, so it fits into the altoids tin. Have fun and share your ideas! Mischka

Posted by mischka 6 years ago


Delay off Circuit 12V - 3A? Mosfet or Relay?

Hi all, I want to make a delay off circuit 12V - 3A. When the switch is ON, the circuit will operate during 1 to 3 minutes, and when the switch is OFF, the circuit should work during 0.5 second before it turns off. I made a delay off circuit using NE555 and a mechanical relay and it works. However, I need to make a smaller, cheaper and more efficient circuit. I need your help and your advice to gain knowledge and improve my circuit. Thank you.

Asked by plantin110 1 year ago | last reply 1 year ago


sliding pot controlling a servo?

I've been trying find a way to recreate this for some time now, but can't seem to figure out the schematics. anybody know?http://www.youtube.com/watch?v=6kQUyc38IHE&feature;=related

Asked by explosive_bagels 7 years ago | last reply 7 years ago



Upgrade LM358 to 25kHZ?

I have a 2khz lm358 square wave generator i want to boost it to 16-25khz max can someone tell me how link is item plus circuit diagram:::  http://www.ebay.com/itm/Pulse-Upgrade-LM358-Duty-Cycle-Frequency-Adjustable-Square-Wave-Module-NE555-/221623454225?hash=item3399c98a11:g:o70AAOSwD0lUfVW5

Asked by TheGreatResistor 2 years ago | last reply 2 years ago



NE555 tesla coil Don Smith ignition coil Tesla coil.....?

I know I've requested info on this previously, but there are still some info I am lacking. The questions I have are these: for the 2 nf capacitors, at what voltage rating would be best to use. For the lack of my own intelligence, could somebody tell me in what direction the power flows? (direction in the diagram) I have almost all the parts save for the nf caps and the 2 diodes. does anyone have a suggestion of what kind of HV diode I could use for the 45KV diode? unfortunately the exact rating with 1-2Amps of a 45KV diode so far is WAY to expensive for me. Any suggestions? What would the approximate power output from the ignition coil be?

Asked by freenergyfuture 6 years ago | last reply 2 years ago


laser beam alarm using NE555 ?? circuit question

Hi all my project idea : using laser beam and LDR to make a security alarm circuit , when the beam is cut , it will trigger the NE55 circuit for certain time (5 seconds only ) there is a lot of 555 dark-activated circuits on the WWW,  i know , but all of them are like on/off switch what i need is one with adjustable delayed time can you help me ??  thanks in advance

Asked by lu2a 7 years ago | last reply 7 years ago


How do you build a small High voltage high frequency power supply? Answered

I need the plans/general guidance to build a high voltage/high frequency power supply like the one used here http://www.youtube.com/watch?v=hUQReIW8f1Q&feature=plcp  . He describes it as "A small ignition-coil, driven by a simple NE555-circuit feeds a 2-stage-multiplier. 12kV out...almost no current, but as you see: Enough to start a fire." Im not sure how to build that. 

Asked by lug big lug 6 years ago | last reply 6 years ago


How to increase NE555 output amplitude?

Hi, I have the following circuit: http://s17.postimg.org/86bus6rm7/Sawtoot_Gen.png which is able to generate a nice sawtooth waveform. When I provide 13.12 volt as power supply, the max peak of the sawtooth will be near to 8.7 volt. There is a viable way to increase this value at least to the same value of the power supply (13.12 volt)? And can someone provide me a schematic based on my circuit? I suspect that this would be viable using a transistor or an op amp on the output, am I right? If i had to implement  an op amp, I prefer to use a "single power supply" op amp, and a common IC (eg an LM358?) Kind regards.

Asked by akopelumenuscu 3 years ago | last reply 3 years ago


What happens when you install electrolytic capacitors backwards? Answered

I built an ignition coil driver with a ne555 timer I think I may have installed the electrolytic capacitor in the circuit backwards. The circuit oscillated then started to die out would this be the capacitor failing?  

Asked by The MadScientist 7 years ago | last reply 7 years ago


220V AC 16 LED ultra bright chaser?

I would like to add LED chaser to this schematic with time delay 400 nanosecond use ne555 and IC 4017. Thanks for the help datasheet for LED ultra bright : 3.5V, 25mA (maks), 12000 mcd?

Asked by ylinggarjati 5 years ago | last reply 5 years ago


What can be added to a 555 Timer output to increase the overall current output?

Since the max output current rating of the NE555 output is 200ma. I would like to increase the current to around 1000ma or 1 amp. I need to drive around 70 LEDs in an on/off (80 on/20 off) duty cycle. Minimal components. Needs to be small.

Asked by keydogstony 9 years ago | last reply 9 years ago


Help with PWM dimmer?

Ello mates,so i biult a pwm dimmer acording to  https://www.instructables.com/id/PWM-dimmer-using-NE555-and-MOSFET-with-DIY-alumini/ but its kinda different,i used irf530n and ne555p ic, And when i connected all of the components with a 12v source it happens nothing except that little spark comes on gnd with adapter? Help please ? 

Asked by JohnSmith-Workshop 1 year ago | last reply 1 year ago


Modulate a transmitter with a signal generator? Answered

Hi I'm doing some experiments with an fm transmitter. Now, instead of transmitting and modulating audio, I wanna try to feed the base of transistor using a ramp generated by a NE555. I ended up with this schematic http://s30.postimg.org/pbe0oyu4x/base_sawtooth_modulation.png , would be ok to pass the signal on the base using a 220 ohm resistor and a 10nF capacitor? I suspect that I have to increase the value of the resistor R5. kind regards.

Asked by akopelumenuscu 3 years ago | last reply 3 years ago


What frequency to use for a gaming steer?

I have an old gaming steer which is not compatible with win 7+, and I can’t find its drivers either. So, im manipulating it on my own, and will use 4 IC NE555 and a potentiometer in astable mode to press [w/s/a/d] with I-don’t-know-what range of frequency. Is there anyone could suggest me use what range of frequency? I thought 700–4000 Hz would be ok. But I have no idea if it is, or not

Posted by Nimasa77 1 year ago | last reply 1 year ago


I need to prevent a battery from discharge?

I want to connect an air pump (5-12v) to a car battery. that battery is also connected to a solar charger panel (seen on other instructables). What i need its a circuit where i can monitor the batterry (a 12v cuttoff) so that when it goes below charge, it turns off the air pump, letting it to freely charge and start again. i thought of a NE555 or a relay. appreciate any help.

Asked by pchalita 9 years ago | last reply 9 years ago


How to boost a sawtooth signal?

Hi, I need to make a sawtooth generator based on an NE555 (the power supply will be 15 volt - 5000mA), and I need to boost the output signal as follow: http://s21.postimg.org/dwz6aynvb/Sawtooth.png Which needs to go from 9.6 volt to 14.10 volt with a 3000mA current. I've found a schematich, but I don't know if is valid: http://s27.postimg.org/9ptmbsbkz/Signal_Boost.png Would be a viable way, using this schematic, or there would be a better/different solution? If so, someone could suggest me another schematic or tell me how to modify the one which I posted? Thank you.

Asked by akopelumenuscu 3 years ago | last reply 3 years ago


How to eliminate noise in FM transmitter? Answered

I had made a FM transmitter using IC NE555. When i power the circuit with 9V battery,the transmitted audio is clearly received in my radio receiver.The problem is the battery will soon drain out and also as the battery starts to drain the transmitted frequency changes without my knowledge.So as the battery voltage decreases the frequency is also changing.To eliminate this problem i used transformer powered source with 9V Regulator 7809.When i power the circuit with transformer the received audio signal on my radio receiver has so much of noise added.The audio quality which i transmitted is completely lost.Anyone Help me to resolve this problem.

Asked by Rajkumar2506 1 year ago | last reply 1 year ago


how are the pins on a ic numbered?

I have been trying to make cylon light bar thing. http://www.evilmadscientist.com/article.php/CylonOLantern but it isn't working, all the wires an connections are done according to what is said and i asked my neighbour to have a look he is a electrician and he was surprised it didn't go as well. its the NE555  i put it togther. looking down on the plastic.     ______ 1-| o  U    |-8 2-|            |-7 3-|            |-6 4-|_____|-5 was that the wrong way? i have seen other circuit diagrams and the pin numbers where not like that. thank you oh and also is some solder non-conductive? and can you burn wires and make them useless? i don't think i could have fried the chip i getting pro at quick soldering.

Asked by Scotty3000 8 years ago | last reply 8 years ago


On the 555 Timer Schematics I found I need help deciding what transistors to use to build it? Answered

I am a beginner in electronic schematic reading and I want to build a full sized 555 timer with all the parts that make up the tiny little IC. But I am having trouble determining what transistors to use. This schematic has the details on what values of resistors to use but not what transistors they are: http://www.electronics.dit.ie/staff/mtully/555%20folder/555equiv.gif Which ones should I use? same thing with this one: http://eliot84.files.wordpress.com/2009/09/ne555-schematic.png This one seems pretty promising since it does list what transistors to use: http://ssihla.files.wordpress.com/2011/02/555.png and I don't know this one is hard for me to understand: http://analogguru.an.ohost.de/193/schematics/Dod_555.gif Which one do you think is best or what transistors could I use in either of the first 2? Is the last one actually a 555 timer or is it something else?

Asked by powerman666 6 years ago | last reply 6 years ago


What to buy if your a beginner

Hello, I'm 13 and I want to get started in electronics. I know how to solder and read basic schematics and I have two of those 200 in 1 electronics sets. I am about to make an order for some components from www.bitsbox.co.uk.This is what I have so far, anything you would add or remove? (I couldn't easily get the quantities)pp3 battery clips2 x AA Battery Holder3 x AA Battery Holder11 wire single core bundle1uF 50V Electrolytic Radial100uF 25V Electrolytic Radial220uF 16V Electrolytic Radial22uF 50V Electrolytic Radial25-way PCB D-connector PlugPrototyping breadboard 80x60Watch crystal1N4001 Rectifier Diode 1A 50VStripboard 95x64White LED 5mm 30000mcd24V 16A SPST K4TA24 RelayPiezo Transducer with Flying Leads7805 voltage regulator (to get a steady 5v from a wall wart for the breadboard)NE555 timer IC2N3904 NPN transistorBC213 TransistorATTiny2313-20PUlm386 op-ampStandard Toggle SPSTupdates:I have a multimeter, resistors and LEDs and I am buildng an attiny 2313 programmer as well as adding to my collection.

Posted by josh92176 11 years ago | last reply 11 years ago


Easy automated method to find chronological age of an integrated circuit design? Answered

This is not a question related to a homework or career assignment. This question is an existential question. Specifically, the thing that I am wondering if it exists, or not, is an easy and automated method for finding the chronological date, e.g. a year, Anno Domini (AD) or Common Era (CE), when a named integrated circuit (IC) was introduced.  Preferably this method exists in the form of a free resource on the Web. As an example, the well known 555 timer IC was introduced in the year 1971, and I am reasonably confident that was the year, because the Wikipedia article titled "555 timer IC", https://en.wikipedia.org/wiki/555_timer_IC contains the words: "Introduced in 1971 by American company Signetics, the 555 is still in widespread use..." And I assume that statement is totally true, because if I can't trust the people who edit Wikipedia, I mean, who can I trust? ;-) Unfortunately, Wikipedia does not have a fact-filled article for almost every IC every sold.  In contrast, a place like www.alldatasheet.com has data sheets for almost every IC ever sold, but, it turns out, the data sheet does not always reveal the year the IC was introduced. To clarify this further, the thing I really want to exist, would be like a web site, with a name like: www.howoldismyic.com, or www.howoldisthisic.com, or www.icdob.com etc. (Please note that none of those URLs point to actual existing web sites, at the time of this writing.) Moreover, I am fantasizing this web site would contain a form, for to enter the name of the IC to look up, and then after hitting the "Submit" button, it would magically tell me what year that IC was introduced to the world, and maybe also which semiconductor company gave birth to it. As some example input and output, the query NE555 would return:  NE555, 1971, Signetics(r) As an additional twist to this fantasy, the query, LM555, would return the same thing, and this magical web page would like, know, that LM555 was a later version of the same IC, except produced by a different manufacturer, namely National(r); i.e LM555 was National's version of the 555 timer . If you have read this far, I congratulate you!  And I appreciate your eyeball time! If you are wondering about my motivation for this question, it is just that think the year an IC was introduced would be a very useful metric, like for answering more specific questions, like: The SG3524 and LTC3780 are ICs used for making switchmode power supplies.  Which of these ICs is more modern? I.e which IC was introduced latest? It turns out, the answer to this question is: The SG3524 is older (introduced first).  The LTC3780 is younger (introduced second). The SG3524 was introduced (I am guessing) in 1977, and that guess is based on some cryptic scribbles in a data sheet for the SG3524, published by Texas Instruments(r). The exact characters were: "SLVS077D – APRIL 1977 – REVISED FEBRUARY 2003" and I am just naively interpreting that blurb to mean the SG3524 was introduced in 1977. Regarding the LTC3780, I think it was introduced some time in the 1990s.  Looking at its datasheet, from Linear Technology(r), I could not find an obvious description of what year it was first introduced, but the first page mentions some US Patent numbers, and looking up those patent numbers, gives dates circa the early 1990s. So the LTC3780 is the younger than the SG3524. However to find that answer, I kind of had to do a bunch of reading of datasheets, and US Patent numbers, and that method took a little bit of work. My question:  Is there an easier way to find out how old (or young) an IC is?  More specifically is there an existing resource on the Web, like a free database, or a IC history site, or something where I can essentially "look up" the year an IC was introduced. By the way there is no absolutely zero urgency attached to this question.  So please answer if you feel like it,  and don't if you don't. I thank you for reading this.  My name is Jack A Lopez, and I approve of this message.

Asked by Jack A Lopez 2 years ago | last reply 2 years ago


AVR, Variable resistors, USB

Hello everyone,What a great site this is, I've only seen like 50 projects so far and I know there are an incredible large amount still left to discover on the site.. for all of you who write the guides and articles, great job! =)So on to my questions..I'm trying to learn how to build and program a circuit with an AVR uC. Previously I've played with NE555 circuits and I've connected those normal HD44780 LCDs to the LPT port and so on..I've also worked with repairing TV sets earlier, replacing both normal components and SMBs..So I got some basic knowledge of soldering and reading schematics, so thats no problem.However the programming part is more problematic and also how to connect some components to the uC.. My wish to learn is how to connect variable resistors to the uC and connect the uC to a computer (via USB perhaps) and then read the values there and perhaps sending them further to another program.More simple, I want to be able to connect a variable resistor to a uC and then be able to read the value and use that value on the computer..In the long run, what I want to accomplish is a similar piece like the Aurora open source mixer. http://www.auroramixer.com/But first I want to learn how to connect lets say 2-3 variable resistors, which I believe should be connected to the ADC channels on the uC, right? Together with a low value resistor between the variable resistor and the uC, I've got that info from somewhere so I hope I'm on the right track.Ok, so that's quite simple, I guess.. But then, how do I read the values on the uC? I think the uC should poll the ADC pins with a few milliseconds in between, or does it work in some other way? Before I connect it to a PC, a simple way to see if it works would be to send the "value" from the variable resistors to a led for each resistor and increasing or lowering the brightness of the led depending on the value from the resistor.That should be quite simple to rewrite when hooking up the uC to a computer, just forward the info the PC instead of to the led.. or to them both perhaps..What would the code be for doing such?My "problem" as most people think, is that I learn by examples, not by books or pages on the net with advanced explanations.. I need to have it quite simple, even though I have no problem learning new stuff..I've been working with PHP programming for a few years and even though I know its far from PHP in a uC, its still programming so I have some sort of basic thinking, which I hope will be handy somehow =)I've searched through the net, also searched AVR Freaks and I've even asked on the forums of AVR Freaks who tells me, sure you can do that, you just have to start programming.. But I really dont know where to start..I learned PHP by downloading examples, see what they do, change a bit and see what happens and so on.. Sure I can do that with the AVR as well, but there are no examples that even read just one pin with a variable resistor connected.. if I had that I would be able to duplicate and make it read on more pins and so on..I should be able to emulate the code somehow with the AVR developer software, so somehow I should probably be able to emulate a variable resistor and find out what values I get from it.. but I havent been able to get something like that working either..Finally, I'm now writing here cause this page hosts a great load of great guides, from "how to sew your own panties" to "building your own waterbottle rocket".. and because I didnt get that much help from AVR Freaks..so you guys are my last hope, I hope you could help me out..// Chrisps. if someone would be interested in making a guide on how to accomplish this and perhaps even connect the uC over USB to a computer, that would be the best thing ever ;) but I'm not gonna go that far, just some help would be enough.. hehe .ds

Posted by toffie 9 years ago | last reply 9 years ago