# How does this work?

Discussion in 'General Electronics Discussion' started by Name..., Apr 22, 2016.

1. ### Name...

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Apr 6, 2016

Can i please have an explanation?

2. ### Gryd3

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Jun 25, 2014
Picture is not showing up. Please try again, or ask a more detailed question.
What do you understand and what in particular do you have trouble with?

3. ### ramussons

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Jun 10, 2014
The IC is a comparator whose o/p is HI. When light falls on the LDR, it goes LO to trigger the 555.
Not too sure about the 555 wiring........

4. ### Gryd3

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Jun 25, 2014
Do you understand the remainder of the circuit?
I think the best thing for you to do is look at a diagram of the 555. It's a simple device really...
IC5 is a comparator. The opamp has a pair of comparators and a flip-flop internally.
The opamps simply trigger when a voltage raises or drops beyond the point set by the voltage divider which is also inside the opamp.
Take a peak, link the picture you are references, and ask again where you may get stuck

5. ### Colin Mitchell

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Aug 31, 2014
I think the best thing for you to do is look at a diagram of the 555
"It's a simple device really.."

Really ????

It's one of the most difficult chips to understand.
Why do you think I have written pages on the operation of the 555, just to get to understand it.

Minder likes this.
6. ### Gryd3

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Jun 25, 2014
I can write a ton of pages on things you can do/build with a hammer...
It's a simple device, it behaves in a known manner. Look up a block diagram to understand how the device operates, and use your imagination to think of different things you can do with it, or look up existing projects.
Just because there are a number of projects that use a 555 different ways, does not mean that the 555 is complicated.

7. ### Colin Mitchell

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Aug 31, 2014
"Just because there are a number of projects that use a 555 different ways, does not mean that the 555 is complicated."

How little you know.

8. ### Gryd3

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Jun 25, 2014
I will admit to not knowing a lot of things. It's what keeps me motivated to keep learning.
Unfortunately though, you seem to feel like you know everything which leads to you making some ridiculous replies and blatantly suggesting ill-suited circuits from your website. I guess in these instances you *can't* be wrong... I mean, you have a website so you must know what you're talking about.

So instead of pointing out how *wrong* somebody is, how about you share your paper on "Why Colin had trouble understanding a 555" with the rest of the class. Other's may find it useful.

dorke likes this.

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Aug 31, 2014
10. ### AnalogKid

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Jun 10, 2015
Does it ever occur to you, for just one millisecond, to disagree with someone respectfully? Do you even know how?

ak

dorke likes this.
11. ### ramussons

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Jun 10, 2014
Is this addressed to me or the OP?

and I think the OP has been truly scared off.....

12. ### Gryd3

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Jun 25, 2014
Sorry, that should have been for the OP

13. ### dorke

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Jun 20, 2015
The 555 is wired at it's most basic way as a mono-stable.
Pin 5 lacks the decoupling capacitor.

When there is light("constant " )on the LDR the output will be "high" ,
thus LED will light-up but the buzzer will be silent.
Is this a bug or a feature?
The op. should tell us...

14. ### Name...

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Apr 6, 2016
Guys dont worry, i know how this works. Sorry for the post from the first place.

15. ### cjdelphi

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Oct 26, 2011
The 555 is pretty easy to understand if you understand how it works

To me, one of the harder chips to understand is a phase locked loop, i've tried to get the damn thing working several times lol

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