Ok, I just dont get it-FINAL PROJECT !!!???!!!

[3v0]

I agree there are basics everyone needs to know. But things are rather specialized these days and people quite good in their own area may look quite stupid to you.

Here what is wrong if you want to do some thing. You start at step A go to step B then to step C. You see what A and B did to get to C. I like C Can't you just give me C that's all I need
And that what's wrong. I like it when some one tell's me what I did wrong with A and B so that in the end I can get C all by myself.

 

[BeeBop]

I agree there are basics everyone needs to know. But things are rather specialized these days and people quite good in their own area may look quite stupid to you.

No kidding!
I have seen this in many ways, but most recently, I have watched native English speakers for the past couple of years, and many of them seem to think that if a second language speaker is struggling with their English, then that person is not intelligent. The fact is, often, that the second language learner is a lot more intelligent than the person making the judgment.

Not much different than the example you pointed to.

 

[Mikebits]

I have to agree with this, and I think anyone who understands electronics should understand a 555, which is just a simple integrated circuit, made of a few transistors ... not too tough to do an analysis to understand how they work

And they do, still show up in many commercial designs...

I never said students don't learn about 555 chips. What I said is that they are not covered at great length as they are not the end al be all of IC's. I also stated that they probably get one lecture during a course.
Granted they are a nice chip, but they are not the Mcshizzle they are made out to be by some on this forum.

Even the book the Art of Electronics warns of the pitfalls with this device and other analog/digital devices like the LS123. Quote from book. "Over usage of these devices is the sign of a neophyte".

I must admit, I do not have much experience in consumer based electronics so Nigels experience would most certainly trump mine and it may very well be that I am completely wrong.

With that said, I would chalk this up to a difference in design philosophy.

While I was under the tutelage of more senior engineers, they always had me stay away from above mentioned devices and warned that they were a poor design practice. All solutions that can be done with a 555 can be accomplished with digital circuits and have a much higher degree of reliability. Then again I never worked on cost sensitive projects either, such as making 1 million game machines...

 

[Nigel Goodwin]

While I was under the tutelage of more senior engineers, they always had me stay away from above mentioned devices and warned that they were a poor design practice. All solutions that can be done with a 555 can be accomplished with digital circuits and have a much higher degree of reliability. Then again I never worked on cost sensitive projects either, such as making 1 million game machines...

Again, you keep saying 'reliability', yet you've probably never even used one - 555's in a properly designed circuit are perfectly reliable, just as much so as a digital circuit.

You seem to be prejudiced against a chip based solely on advice from people who have also probably never used one, and never had to design in the real world.

I would imagine that the said 'senior engineers' were digital only, and had no analogue experience - which cripples their usefulness (just as the other way round would of course).

 

[q5101997]

Education

I'de figured why a BJT has 3 pins at 9 YO. I'de figured out that a CPU needs a ROM at 14. If I had been formaly trained I probably would have had my degree by 18. The education system in Australia is pitiful.

 

[be80be]

Again, you keep saying 'reliability', yet you've probably never even used one - 555's in a properly designed circuit are perfectly reliable

Just run It on 5 volts then
you can say it's digital 0 volts logical Low 5volts logical high
It's all good we the learners need to learn more. And you know the last part.

 

[3v0]

If a circuit need logic it makes sense to use a microcontroller rather then a 555. The 555 is about 20 cents. A 6 pin baby pic at about 50 cents and 8 pins for 70.

For that reason I doubt you will find many 555's anymore outside of hobby use. I do not look inside a lot of equipment like the repair guys so I am guessing. But it seems to make sense.

 

[dknguyen]

Personally, I find it very difficult to find a charge pump IC capable of 18V. 555 timer seems to be the only one. For timing purposes...yeah I probably wouldn't use a 555 since there seems to be lots of other "digital" things available. But how many digital ICs do you know that run off 18V? 555 timer strikes me more as a switching controller for power purposes rather than digital logic device.

 

[DSGarcia]

Engineers can't light a light bulb? I found this blog on the Control Engineering web side. Graduating MIT engineering students couldn't light a simple light bulb using a battery, wire, and a flashlight bulb.

**broken link removed**

The blog references the 55 minute video "Minds of Our Own" and is worth viewing (a free registration is required) found at: **broken link removed**

 

[OutToLunch]

I would hope any graduate would know about 555's, they are a very useful chip for all kinds of purposes, and often used in industry and domestic products. Perfectly reliable chip for a great many purposes.

I don't see any reason why you would want everyone who graduates to know about the 555 or the 741 or any other general purpose IC that you can think of.

What really needs to be taught is the ability to read a datasheet and other supporting documentation for any IC and getting a good understanding of how the IC works and what its limitations are prior to its use or even selection. I can't even remember if I was exposed to the 555 while in college. I can tell you I've never used it since. I can't recall ever using the 741 outside of college labs either - yet they stuffed that amp down our throats as much as possible (they must have gotten a boatload of them for free). One thing they never did was to go through the datasheets and point out how to extract the useful information from them. That's something I had to learn on my own.

 

[Nigel Goodwin]

I don't see any reason why you would want everyone who graduates to know about the 555 or the 741 or any other general purpose IC that you can think of.

Would you employ a supposed Electonics 'graduate' who had never heard of a 555 or a 741?. Both chips manufactured in the multiple millions (if not billions?).

Any such graduate obviously doesn't have the slightest interest in Eelectronics, which I would consider a serious failing - I must admit I've hardly ever used 555's myself, perhaps ten (if that) over all it's life - but using and knowing how to use are totally different things.

Over the years I've interviewed various people for service engineer jobs, and also kids on work experience - three things I ALWAYS do:

1) Ask them if they know their resistor colour code.

2) If they say YES - then I throw them a 'difficult' resistor
2) If they say NO - then I throw them an 'easy' resistor.

3) Ask them what projects they have built.


The third one is the really telling one, anyone worth employing will have made all kinds of projects, will be able to bore you to death about them, and generally lose their nervousness while doing so.

For a graduate I would expect to hear about projects he did long before he went to Uni - I wouldn't want anyone who didn't have the 'drive' and 'enthusiasm' for electronics before then.

 

[mvs sarma]

The level of knowledge should be such that an Engg graduate when he comes across ( as most of us come across many many new chips in daily life), should be able to analyse it from the data sheet and be able to use it or solve a problem(as and when presented) using his acquired abilities. At lest he should not say like a child that this obsolete and I am modern. In real life many engineers come across old equipment and old designs.

I clearly mean, an education can create capability but not thoroughness of all chips made so far. But one may not say i don't know this, at least without putting some effort and be able to analyse the principle behind.

This is what the enthusiast are able to do. This is what is lacking in modern engineers coming out of the academic centre to takeover the tech community.

These two chips are called by my mentor, as Industrial workhorse and industrial timer those days way back in70s.

 

[Mikebits]

By reliability, I am not talking about part failure, rather repeatable results from lot to lot, temp and voltage.

I have worked in the real world more so than you might guess. I worked at a Company that did well, hired the best and afforded me the option to retire early and persue other interest. For example; going back to school.

The senior engineers I speak of did not become senior level because they were limited.

 

[Nigel Goodwin]

By reliability, I am not talking about failure of the part. Rather repeatable results.

This is like an engineering problem - you don't specify 2.5 inches, you specifiy 2.5 inches +/- your tolerance. If you want a simple squarewave oscillator at 1KHz +/- 20% a 555 is just as good as any expensive digital solution you care to name - if you want 1KHz +/- 0.001% it's an entirely different thing.

You seem to be prejudiced against a chip based solely on advice from people who have also probably never used one, and never had to design in the real world.

The real world? Do you not consider cellular base stations real world?

No, it's a very tiny specific niche market - and I fully agree that there's likely to be very little use for a 555 in that field

I would imagine that the said 'senior engineers' were digital only, and had no analogue experience - which cripples their usefulness (just as the other way round would of course).

Well you imagined incorrectly. Many of these engineers were experienced ex M/A Com Linkabiter's. The name should speak for itself. The company I worked for was an offspring of Linkabit, which became Qualcomm (Perhaps you heard of CDMA, The GSM alternative).

Never heard of any of those companies - and presumably they are almost entirely digital?.

 

[Mikebits]

Ah you answered my pre-edit... Ack your quick

 

[Mikebits]

Well, I am not trying to get your shorts in a bunch, I think we just have a difference in thinking on this matter... Fair enough
Like you said, I never worked on designs that allowed wide tolerance.

 

[Nigel Goodwin]

Well, I am not trying to get your shorts in a bunch, I think we just have a difference in thinking on this matter... Fair enough
Like you said, I never worked on designs that allowed wide tolerance.

Like I said - not in the 'real world'

 

[Hero999]

I've never understood why any one would use a micro rather than a 555 if all they want is a cheapy oscillator that doesn't have to be accurate.

I could solder a 555 circuit on a piece of veroboard quicker than I could program a micro.

A 555 also has the advantage of been able to drive a 200mA load and work off a very wide power supply voltage 2V to 18V depending on the type of 555 used.

For a simple oscillator glue logic also normally works out much cheaper than either a 555 or a micro.

 

[3v0]

Electronics has fragmented. Each fragment tends to have it own view of what is.

In my mind the scope of what you can do without a microprocessor is limited. A recent CC article used an AVR on a coil gun to monitor the output.

I've never understood why any one would use a micro rather than a 555 if all they want is a cheapy oscillator that doesn't have to be accurate.

I agree but do not often see a unicorn. Perhaps more exist outside my bragment.

 

[Nigel Goodwin]

I've never understood why any one would use a micro rather than a 555 if all they want is a cheapy oscillator that doesn't have to be accurate.

You wouldn't generally - but if you want it accurate, want it to have a massively greater range, then an 8 pin PIC has the same footprint and will out perform a 555 by an incredible amount.

For example - you want a timer that gives accurate settings of 1 hour, 2 hours, and 3 hours - not a chance with a 555, but trivial with a PIC.

On the other side, you want a timed (anti-thump) delay on the speaker output of your amplifer - no great accuracy is required, but a relay feed is - a 555 is a better choice than a PIC for that (unless you can find something else for the PIC to do?).

Choose the correct device for the job, don't get stuck trying to force a poor choice on something it's not good for - a big advantage of PIC's is that they easily improve most functions you use them for.