"Perfect" LED current limiting challenge

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jimandy
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Re: "Perfect" LED current limiting challenge

Post by jimandy » Sat Jan 07, 2006 5:14 pm

Just wondering, chris, is there something wrong with the period (.) key on your computer? You seem to end a lot of declarative sentences with a question (?) mark.

<small>[ January 07, 2006, 05:15 PM: Message edited by: jimandy ]</small>
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Chris Smith
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Re: "Perfect" LED current limiting challenge

Post by Chris Smith » Sat Jan 07, 2006 5:27 pm

Nope, its called leaving it open to interpretation. [not mine]

I actuall have to guess like every one else, so why pretend its a statment or fact if you dont know.

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Re: "Perfect" LED current limiting challenge

Post by jimandy » Sat Jan 07, 2006 5:37 pm

Ahhh, that's a good answer. So now maybe we can close the door on this topic and all go home.
"if it's not another it's one thing."

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philba
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Re: "Perfect" LED current limiting challenge

Post by philba » Sat Jan 07, 2006 5:48 pm

Originally posted by ian:
Guys, I suggest you stop trying to refute Chris' nonsense, believe me, he can go on forever spewing this kind of crap. For every dopey thing you refute, Chris will add two more.
I'm very familiar with his type. there are two traits that stand out.
1) he is a troller. always trolling for controversy to start an argument. I think he derives some sort of sick sustenance from fighting with people. I had a brother-in-law who was like that. always looking for something to argue about, what drag to be around him.
2) he is incapable of letting anyone else have the last word. I don't care how silly or stupid it is, he will say anything to get the last word in.

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Chris Smith
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Re: "Perfect" LED current limiting challenge

Post by Chris Smith » Sat Jan 07, 2006 7:45 pm

The other foot in the mouth person trys to recover a piece of his lost body parts?

No sale phil, you stuck your foot in it, but you can bow down and say you got it wrong.

People will accecpt it because we know you have never worked in this field before.

20,000 ns packets @ 50kcps 99:1
1% duty cycle

20 ns on
19,980 ns off
20,000 ns per packet

50,000 cps at 100 amps = Less than a 20 milliamp DC draw


200 ns on
19,800ns off
1% duty cycle

20,000 ns per packet
1000 cps at 100 amps = .002 amps

<small>[ January 08, 2006, 10:25 AM: Message edited by: Chris Smith ]</small>

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Re: "Perfect" LED current limiting challenge

Post by Jarhead » Sun Jan 08, 2006 1:17 pm

Chris,

Directly from one of the laser diode manufacturer's websites:

Sensors: Laser Diodes
Q: What is duty cycle?

A: Duty cycle or duty factor (DF) is the length of time the laser diode is actually lasing. It’s also referred to as the “on” time of a laser; and is usually expressed in percentage. For a pulse laser and quasi CW laser, the duty cycle is equal to the product of pulse width (Pw) and pulse repetition rate (PRR):

DF % = (Pw x PRR) x 100
http://optoelectronics.perkinelmer.com/ ... x?FaqId=90

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Chris Smith
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Re: "Perfect" LED current limiting challenge

Post by Chris Smith » Sun Jan 08, 2006 3:47 pm

Jarhead....As I have stated, there are many ambagious uses of the term "Duty Cycle".

This doesn’t make them correct or incorrect, just ambagious when misused or no attention to detail is considered.

However with out question or ambiguity, the term "Duty Factor" covers all the above because it is the only true total "accumulation" of all the terms or ratios.

When You consider that:

This is a duty cycle of 1%

"200 ns on
19,800ns off"

But this duty cycle is less than 1%

"20,000 ns per packet
1000 cps at 100 amps = .002 amps"

And it takes both to run a laser.

When you consider you must add both of these seperate equations above to state a value or rating, and both formulas above use the same term of Duty Cycle to come up with their individual sums, You must then use a final and un-ambagious term to describe both for your total formulae unless ambiguity is accecpted.

Thus the term "Duty Factor" is the CORRECT TERM for this exact reason and its general meaning in all fields of electronics is roughly the same.

“A sum of all the factors above”

Duty cycle does not cover this compound meaning but often is incorrectly applied with out thought or reason.

But then none of this gets us any closer to the statment I made which is that a 100 amp pulse circuit can draws less current and have less heat disapation than a DC 20 milliamp circuit running a led, for the reasons already stated, and then blurred by some.

When ever some one doesn’t want to learn, they side track and blur the edges instead of listening or learning.

They don’t question, they scoff or reject out right because they have no imagination or scope of thought.

I have met several here, and even more in real life, and all of them are very small minded losers.

And they never learn from their mistakes because they are proud to be ignorant.

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Re: "Perfect" LED current limiting challenge

Post by rshayes » Sun Jan 08, 2006 7:00 pm

Chris ignores the basic point. The purpose of a laser diode or an LED is to emit light.

Ian's original question was how to extend the battery life while operating an LED. In most applications, such as indicators and flashlights, amoung many others, the average light output is the significant factor. The human eye is an averaging device.

Operating an LED with high pulse currents does not solve this problem. It reduces the efficiency of the LED and requires such low duty cycles to control the heat dissipation that the average light output drops to practically nothing with no reduction in power consumption. It is not a solution to the problem that was posed.

If you read very many of Chris's posts you will find that they usually contribute nothing toward actually solving a problem that has been posed. In general, they are poorly written diatribes proclaiming everyone else's ignorance. Chris appears to see himself as a verbal Samson slaying the Phillistines. He is even armed with the same weapon.

Many of Chris's comments are more autobiographical than anything else. For example:

"When ever some one doesn?t want to learn, they side track and blur the edges instead of listening or learning."

"And they never learn from their mistakes because they are proud to be ignorant."

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Chris Smith
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Re: "Perfect" LED current limiting challenge

Post by Chris Smith » Sun Jan 08, 2006 7:52 pm

And again Steven, you speak from years of personal experience in this field?

Best to keep quiet Steven, when your foot is lodged and blocking the common sense from coming out.

What you know about extending battery life from a REDUCTION in power due to a smaller duty and factor cycle seems to parallel your experience in most matters and subjects here.

You try to de-focus from the issue soo well, but like your experience in all matters here, you fail in such a natural way as to make us believe you really are a shoe salesman.

If you cant be a good example
Be a Terrible warning

<small>[ January 08, 2006, 09:21 PM: Message edited by: Chris Smith ]</small>

rshayes
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Re: "Perfect" LED current limiting challenge

Post by rshayes » Sun Jan 08, 2006 10:08 pm

"And again Steven, you speak from years of personal experience in this field?"

Yes. I built equipment using LEDs in 1967, which is slightly before Chris dropped out of the ninth grade because he was too smart to be educated. After that, I worked on a project for several years using lasers to scan a scene and record it on color film. Since then I have designed and built many other types of electronic equipment.

"Jarhead" probably has more experience working directly with diode lasers, and he isn't supporting Chris either.

On other threads, Chris has talked about his extensive experience in a plant that plated chrome onto car grills for General Motors. I fail to see how this experience relates to the problem that Ian posed, or to LEDs or diode lasers.

He also has failed to explain how using the same energy to produce less total light will increase battery life in Ian's posed problem.

<small>[ January 09, 2006, 01:01 AM: Message edited by: stephen ]</small>

Mike6158
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Re: "Perfect" LED current limiting challenge

Post by Mike6158 » Mon Jan 09, 2006 5:11 am

On other threads, Chris has talked about his extensive experience in a plant that plated chrome onto car grills for General Motors. I fail to see how this experience relates to the problem that Ian posed, or to LEDs or diode lasers.
Well duh... LED's shine on chrome and it looks pretty...

By the way... that's not a slam on Chris. It's an attempt to lighten this pitifully vitriolic thread up. This thread has devolved into a huge pissing contest that's not much fun to read. The only reason I keep the email notification checkbox "clicked" is the hope that useful information will someday return to this thread...

<small>[ January 09, 2006, 05:14 AM: Message edited by: NE5U ]</small>
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Re: "Perfect" LED current limiting challenge

Post by ian » Mon Jan 09, 2006 10:27 am

Just trying to trigger NE5U's email notification box.........

Mike6158
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Re: "Perfect" LED current limiting challenge

Post by Mike6158 » Mon Jan 09, 2006 10:34 am

ROFL :D It worked... Gee whiz thanks a ton for the thoughtful and informational post :D
"If the nucleus of a sodium atom were the size of a golf ball, the outermost electrons would lie 2 miles away. Atoms, like galaxies, are cathedrals of cavernous space. Matter is energy."

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Chris Smith
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Re: "Perfect" LED current limiting challenge

Post by Chris Smith » Mon Jan 09, 2006 12:38 pm

Well actually we made Ford hubcaps out of plastic, and chromed them amongst many other things.

A science unknown to the world before Crown City Plating pretty much Invented it commercially.

Inventing and Getting chrome to stick to plastics is not for amateurs.

So as dirty or simplistic as this trade may seem, high tech was not left out as the company held more patents in chrome plating than any one else in the world, not to mention electrical techniques on how to accomplish it.

And Im sure that wont remain true for ever.

And then we used lasers to mark parts which also has nothing to do with chrome plating per se, and everything to do with lasers.

And then I personally have more than twenty years invested in Research on high power pulsing just for my own personal satisfaction.

But, when you look into the field of electronics, 99% of the technicians steer clear of optics and lasers because they just don’t have a level of understanding needed to accomplish anything.

Just One of the Reasons I found so much interest in it.

Its called, stay clear of the crowd, and you will always have a job.

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Dave Dixon
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Re: "Perfect" LED current limiting challenge

Post by Dave Dixon » Mon Jan 09, 2006 1:30 pm

Chris, I seriously must learn more from you. Your company invented chrome, as well as invented a procedure to stick it to plastic?
If it isn't too proprietary, could you give me a hint on how the chrome was stuck to the plastic using "electrical techniques"?
Did the company buy commercial "Off the Shelf" lasers and merely operate them, or were they designed and built there?
I don't think I want to know about "High power pulsing, for your own personal satisfaction" That's already too much information for me to consider.
I am interested in the electronics technicians that you seem to hang with. The techs that I know are generally knowledgeable with optics. 1% seems hard to believe!
With all DUE respect, thanks in advance for your answers.
Dave

<small>[ January 09, 2006, 01:31 PM: Message edited by: Dave Dixon ]</small>

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