Feel better now ?
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Feel better now ?
Last edited by mister_e; - 3rd April 2008 at 03:07.
Steve
It's not a bug, it's a random feature.
There's no problem, only learning opportunities.
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It's hard to argue that one isn't it? I don't go out of my way looking to pick people up on their errors, but I just couldn't ignore your comment, because it goes against the very foundation on which electronics is taught. You will never have a true appreciate of electronics without it. Just tell yourself that is was a typo -- because I do indeed believe that you are crafted with this "appreciation" and just happened to have overlooked it this time. My reasoning for saying this is because you haven't argued it.Originally Posted by mister_e
Feel better now ?
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Dave, I have never seen a max life value from Microchip for a PIC - do you have a reference for this?
Trent, I have never seen reference to microchip PIC life reduction if run at the high end of datasheet-listed allowed speeds (or voltages for that matter). Can you provide reference to this?
Trent, Would Einstein not have been correct with his theory of relativity if he had been challenged and had not replied? (ref: TRENT - My reasoning for saying this is because you haven't argued it.)
Paul Borgmeier
Salt Lake City, UT
USA
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You sound like my university tutor marking me down in an assignment for not referencing something in an essay. Best I could do is hand you a 300pg text book on basic electronics and let you decide for yourself as to whether or not there is questionable truth in what I'm saying. I say this because there is no one paragraph, or even just a couple of pages that could be used to support it. You need the whole book, even then you may not conclude that what I'm saying is true.
I know it's besides to the point, but Einstein was actually challenged in his younger years.Trent, Would Einstein not have been correct with his theory of relativity if he had been challenged and had not replied? (ref: TRENT - My reasoning for saying this is because you haven't argued it.)
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http://ww1.microchip.com/downloads/e...cs/00097AB.pdf
Not max life values. Just the reliability report.
Dave
Always wear safety glasses while programming.
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In the kind of things ill be making (disco lights / pinball machines etc) i would be happy if the chips lasted 10 years. The biggest heat problem i have will be my pinball machine. There are so many lights under the playfield and in the ones ive done in the past it gets quite warm in there but i dont think its enough to harm anything. The drive chips got hotter than the bulbs and they still work fine... except that one that was connected to the wire i accidentally shorted out :P The new one will be slightly ventilated anyway.
Is it just heat that makes a higher speed shorten the life? Could it be possible that doubling the speed doesnt make it heat up too much and so it doesnt shorten the lifespan much? (just a thought)
So, as long as theres no power issue (like running from a battery) and the lifespan isnt critical then using a faster resonator doesnt really make any difference? I suppose it does give you the chance to use that speed in the future though without having to solder a new resonator in
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Hi,
The main problem is not run time, but ON/OFF powering count and "violence" ...
design carefully your power supplies, take care of your I/Os , use the "cool startup" features now provided, and your Pics will last ... How much is the MTBF given in Dave's document ???
LOL !!!
Alain
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Why insist on using 32 Bits when you're not even able to deal with the first 8 ones ??? ehhhhhh ...
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IF there is the word "Problem" in your question ...
certainly the answer is " RTFM " or " RTFDataSheet " !!!
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If you are worried about heat, get the industrial version. The 16F877A for example will handle 85C. Check the end of the data sheet for the PIC you plan to use.The biggest heat problem i have will be my pinball machine. There are so many lights under the playfield and in the ones ive done in the past it gets quite warm in there but i dont think its enough to harm anything.
And like Alain, design carefully.
Dave
Always wear safety glasses while programming.
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The difference is negligible, but it is important to be aware that a difference does exist. We're talking nano watts of power with many integrated circuits, (increased thermal dissipation is negligible) but if we were to turn the subject into say watts then difference could become very significant.
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Whats MTFB? Im guessing mean time before failure and yeah, they seem to last quite a long time.
Im not that concerned about heat. My pinball is probably the hottest place they will go and that should never go above about 30 degrees even on a hot day (yeah, our hot days are about 15 degrees!)
The on/off count i expect to be high while testing things. I always put safety switches on to cut the power to the whole playfield as soon as you lift it up and i do tend to turn things on and off a lot when im testing (maybe a few times a minute). Once everythings up and running i expect they will stay on most of the time (might turn it off at night).
How do i take care of I/Os? All my outputs will go directly into some driver chips and the inputs will go to switches with a 10K grounding resistor. Is that fine?
Whats cool startup?
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An unsupported argument against the claim that Einstein was a poor student: http://www.abc.net.au/science/k2/moments/s1115185.htm
An unsupported premise for it: http://findarticles.com/p/articles/m...57/ai_68648469
I think the truth is somewhere in between.
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This is what Microchip told me
Steve
It's not a bug, it's a random feature.
There's no problem, only learning opportunities.
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Well that clears that up!
Dave
Always wear safety glasses while programming.
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I agree completely with the Microchip reply...
However, doesn't it looks too much like a 'canned statement'?
I wouldn't doubt that, all other things being equal, a PIC running at 20Mhz would fail sooner than that exact same PIC running at 4Mhz.
But how much sooner? What kind of time scale are we talking about here? Would any of us, or our offspring be around to mark the time at which one or the other failed? Kind of like measuring how long an EEPROM will hold data. EEPROMs haven't been around for the 100's of years it would take for one to supposedly degrade and lose data.
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