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Learn about the 555

Picture of learn about the 555
In this instructable i will teach you every thing you would ever need to know about the 555 timer IC. If you already know about the chip you could check out my slide show titled "47 projects to do with a 555" it will teach you every basic project to use a 555 with, its great for beginners! 


I do not take 100% credit for this. source link on each step.
 
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Step 1: An overview of the 555 timer

The 555 Integrated Circuit (IC) is an easy to use timer that has many applications. It is widely used in electronic circuits and this popularity means it is also very cheap to purchase, typically costing around 30p. A 'dual' version called the 556 is also available which includes two independent 555 ICs in one package.

For the 555 to function it relies on both analogue and digital electronic techniques, but if we consider its output only, it can be thought of as a digital device. The output can be in one of two states at any time, the first state is the 'low' state, which is 0v. The second state is the 'high' state, which is the voltage Vs (The voltage of your power supply which can be anything from 4.5 to 15v. 18v absolute maximum). The most common types of outputs can be categorized by the following (their names give you a clue as to their functions): 

Monostable mode: in this mode, the 555 functions as a "one-shot". Applications include timers, missing pulse detection, bouncefree switches, touch switches, frequency divider, capacitance measurement, pulse-width modulation (PWM) etc
Astable - free running mode: the 555 can operate as an oscillator. Uses include LED and lamp flashers, pulse generation, logic clocks, tone generation, security alarms, pulse position modulation, etc.
Bistable mode or Schmitt trigger: the 555 can operate as a flip-flop, if the DIS pin is not connected and no capacitor is used. Uses include bouncefree latched switches, etc.

http://www.555-timer-circuits.com/an-overview.html

 
Nishi200113 hours ago

Im having a problem that my NE555 ics doesnt work in any circuit.ihave ne555p and ne555n

Greetings, i'm having a problem with a light follower robot im trying to make from C.V.Hariharans' project using 555 timer , could someone please help me because i'm not getting any answers from the instructables' author ?
TomK322 months ago

Regarding the name of the 555, you are wrong, Hans Camenzind himself stated that the name was chosen by the Marketing Manager because they excepted it to be a successful IC. http://www.semiconductormuseum.com/Transistors/LectureHall/Camenzind/Camenzind_Page2.htm

I just got some Texas instrument tlc555ip chips can I use them in any project that would require a 555 chip?
LGT3002 years ago
does it has to be ne555 or could be something else
Jimmy Proton (author)  LGT3002 years ago
I'm not entirely sure what the letters mean but I think it has something to do with the amount power it can take. You may find it in here.
Jcfowler3 years ago
Ok so... I'm pretty new to this 555 timer and I guess the first part I'm a little blurry about is the "trigger" pin.. It states that it detects 1/3 of the rail voltage (Which I'm assuming is the actual voltage source, I've never heard the term used) to make output HIGH. My question is that when making the output HIGH, is it making the voltage 1/3 of the original source?
Jimmy Proton (author)  Jcfowler3 years ago
I think is means energized as in if you were making an AC current it would turn off(LOW) and on(HIGH). Thats what I think, I dont actually know though.
http://www.ehobbycorner.com/pages/tut_timer.html
Thanks man. I found this link to be very helpful as well if you're still blurry on it.
I guess my hand at electronics isn't that good. First off, what is a 0v power supply? Plus, you may want to illustrate how (in step 2, description of pin 7) is, because it my mind it's jumping up and down from several terms in electronics. In short, I get confused at that part, so please do add some form of illustration.
Jimmy Proton (author)  nutsandbolts_643 years ago
0v is negative although it should be positive because electrons go from negative to positive (its talking about a DC power supply). and i dont know the answer to that question.
Oh... Once I get what you mean by the aforementioned description of pin 7, I'll attempt to make an illustration of how it works.
Jimmy Proton (author)  nutsandbolts_643 years ago
I didn't make this stuff up so I dont know what all of it means.
Oh.... OH, right, I forgot, you got the info from another source...
Jimmy Proton (author)  nutsandbolts_643 years ago
if you go to the link there's a contact page you ask it on.
AndyGadget3 years ago
Jimmy, this is an extremely good guide to the 555 but has been lifted from another website, as you partially acknowledge at the end. This guide also appears in other places on the web, but for it not to be in breach of copyright you need the permission of the original author, either personally or in his general statement of copyright terms.  Not doing so is against section 8f of Instructables rules.

Jimmy Proton (author)  AndyGadget3 years ago
I have permission from the author.
You may want to detail that in the instructable itself so that it doesn't get pulled when this comment thread is drowned amongst the others that will surely come.
Yep, put a credit to the author in the Instructable - Something along the lines of "Material used by permission of xxxxxx with content from XYZ.com."
It's always good to give credit where credit's due, and to tie up any potential ownership disputes before they arise.
Keep up the good work.
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