icaxe 08M lifetime?

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ChedderCheeser

Senior Member
Hi guys. What is the average lifetime of an o8M? I plan to run one for a long time, and.. just want to know.

EDIT: Picaxe! Not icaxe!
 
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NXTreme

Senior Member
The datasheet for the Pic the Picaxe is based on should help out a bit. But, if I was to just guess, I'd say that ten years might be normal, if the Picaxe is well protected in any and every way. Just watch out for those lighting strikes, they kill ;).
 
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MartinM57

Moderator
Good question :)

The 08M underlying PIC (PIC12F683) datasheet says:
Flash/Data EEPROM Retention: > 40 years
Click to expand...
So I'd say more than 40 years....(if operated within all other datasheet specifications)
 
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manuka

Senior Member
If you are only 12 yo., teenage turmoil may bring more destruction to your PICAXEs than lightning strikes. Report back in 2020 maybe!
 
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westaust55

Moderator
Data retention isbased on how long a program will "survive" without corruption once programmed into the PIC flSh memory.

A couple of other statistics which may Ned to be taken into account are:
The number of times that you can reprogram the PIC - Flash memory endurance, and
The number of time you can rewrite the data in EEPROM memory.

Again looking at the data sheet for the PIC chip will give this data.
See PICAXE manual 1 for a list of most PIC chips correspondingly used by Rev Ed. There is the new M2 release notice thread which gives a guide to the datashet for the corresponding PICs for those M2 parts.
 
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fritz42_male

Senior Member
I did my college industrial training with a chip manufacturer (Siliconix). We found that one of the main reasons for chip failure at the time (may be different now) was thermal stressing. The actual bit of silicon was bonded to the substrate of the package with a glue. The glue would stress with every expansion and contraction of the chip on power on/power off and eventually the glue would fail, the silicon break away from the substrate and for one reason or another, the chip fails. We had big stressing ovens to do our testing and one of my hobs was repairing the test boards - usually with Kynar wire (I used to be able to strip Kynar perfectly with my teeth - wouldn't chance it now as I have $thousands worth of veneers on my teeth!)

So, the lifetime was defined primarily from the number of power on and off cycles for the circuit.

As I say, it may be different now but I think the power on/off things still holds true so if the chip is continuously on (even in low power sleep mode) then it will probably last a lot longer than otherwise.
 
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Paix

Senior Member
Well, D2, the alarm LED appears to be reverse biased. D1 and D3 appear to be good.

I suppose that if the alarm goes off you might notice the blocked drain rather than the LED.

Sounds like a sound investment anyhow; thanks for sharing.
 
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Dippy

Moderator
"What is the average lifetime of an o8M?"
- if it's in one of manie's MOSFET circuits then probably about 3 seconds :)

I've got an electronic circuit that has been running since 1620.


Papa; no need, just promise us that you'll clean your drains more regularly.

PS. This is what my old college lecturer used to keep babbling on about wrt electronic failures.
http://www.weibull.com/hotwire/issue21/hottopics21.htm
 
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nbw

Senior Member
I've had an 18X running the espresso machine monitor for 3 and a bit years, every day, no glitches at all - and 5,253 cups. It does memory reads and writes (cup count updates) every day. Also uses a Rev-ed ultrasonic module to measure the amount of water in the reservoir, that's been working well too.

My wife says I will get a break once I've made 10,000 cups.

Maybe.
 
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srnet

Senior Member
The 08M I would not be worrying about.

Far more likley to fail, in my experience, are all the things that connect the chip to the outside world, IC sockets, connectors, switches, wires, solder joints, PCBs etc.
 
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John West

Senior Member
srnet said:
The 08M I would not be worrying about.

Far more likely to fail, in my experience, are all the things that connect the chip to the outside world, IC sockets, connectors, switches, wires, solder joints, PCBs etc.
Click to expand...
Bingo! In the long run, mechanical problems are the most likely suspects for failure, as long as good design practice and good power supplies are used with the PICAXE. Oxidation and corrosion and wear of all types in all mechanical components is a bigger threat than the electronic failure of a PICAXE.

I can't tell you how many times I've repaired expensive electronic equipment by simply re-seating IC's in their sockets. (Although most recently was last Friday.)

Which brings up one of my suggestions for maximum reliability. If you must socket any IC's, (although soldered in place is best) be sure and use machined-pin sockets for best reliability. The socket will cost half as much as a typical PICAXE, but they're worth it if you want your projects to keep on working year after year. I have yet to find a machined-pin socketed IC connection that was the problem in any defective circuit, however old.

Finally, I'd suggest properly sizing and using only the best high-temperature rated electrolytic capacitors in any project you hope to operate 24/7 for many years. From my experience, they are the most likely electronic failure point in long-running equipment.
 
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Dippy

Moderator
"as long as good design practice and good power supplies are used with the PICAXE"
and srnet's post.
- Wise words.

A circuit is a wholistic (I hate that word) thing; physical and electrical.
So often, especially with novices, we'll see a circuit that has been cut'n'paste from some Internerd site , or guessed at.
Or a good circuit compromised by tight-ass cheapo or unsuitable selection of components
I'm sure we've all been there at some stage. And hopefully we've learned.

It's all very well having a 40 year (haha) MTBF PIC but when you've got a red-hot regulator or h'penny ting-tong electrolytic capacitors then, as said above, the 08M is the least of your worries.

Read , Listen, Learn, calculate,test,measure,select,design, test, make.
And if you can't be bothered to do any of the above then you should stick to selling ice-cream :) and I'll have a 99.
 
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papaof2

Senior Member
Dippy;175284Papa; no need said:
Not my drain. It's the drain for the outside stairway to the basement at my daughter's house. It's possible to have enough leaf-fall in one day to block the drain, thus the alarm. It's saved the basement from flooding at least twice since it was installed, so well worth the time and small cost.

John
Click to expand...
 
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