Questions tagged [lifetime]
80 questions
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What happened to electrolytic capacitors in the 21st century?
We can sometimes see decades-old capacitors (such as ones made in the USSR) still working. They are bigger and heavier, but durable and not desiccating. Modern aluminium capacitors serve for about 11 years, if you are lucky, then become dry and…
Incnis Mrsi
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Why hasn't my LED burned out by now?
I have a 15 year old ReplayTV DVR. I got it used, I'm not sure when, but probably about a decade ago. It's turned on almost all the time, and it has a blue power LED on the front.
The LED FAQ says that many LEDs have a rated lifetime of 50,000…
Barmar
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Microcontroller shelf life
Our purchasing department requested the AT32UC3B1256 and the supplier has a few thousand in storage. However, those trays have a date code from 2009.
While shelf life is normally not much of an issue with integrated circuits, 10 years is quite a…
Rev
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Does (and when how) the lifetime of a LED depend on the PWM frequency
Let's assume two options for driving a standard LED at its rated current.
PWM set to 50% duty cycle at 10 kHz
PWM set to 50% duty cycle at 50 kHz
Technically both LEDs would produce the same amount of light and the 'blinking' won't be visible to…
Gilad
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Do components have an un-used lifespan?
Lets say for example, that I had a box full of transistors, resistors, capacitors, diodes, leds, this and that, and left it in a cool, average environment for lets say... 50 years.
Do these components have a lifespan while been unused? Do the…
user62118
21
votes
4 answers
Do conductors age under reasonable electric load?
Construction steels are prone to fatigue failure - they get structurally weaker when exposed to repeated mechanical stress.
Is there any similar process for conductors which makes them less usable once they conduct current for long enough?
In other…
sharptooth
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How do LEDs slowly degrade in normal use?
As I understand it, an LED normally has a service life of perhaps 25 years with output that decays exponentially as a function of time and current.
What causes the degradation? I'm guessing that the current is slowly moving atoms around in the…
Dov
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Wouldn't charging a lithium battery to 80% only defeat the purpose of putting the battery into longer use in the first place?
I see most smart devices (laptops/tablets/phones) now have the option to optimize your battery by charging it to 80% only.
But wouldn't this reduce your capacity i.e. your brand new battery now only has 80% of its rated capacity, which means more…
GuitlyofNtAsking
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What causes loss of power over lifetime of a magnetron?
The power of a magnetron declines over time\$^1\$. While not noticable for most consumer applications (A 2000-hour lifetime would last over 20 years if the device is used only 15 minutes a day), this is a problem in industrial situations.
What…
Joren Vaes
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Life Expectancy of Power Supplies
There are many articles on the internet about life expectancy of switching power supplies, but most of them have discussed about the situations that the PSU is at near full load. I'm designing an electronic device that needs a standby state, I'm…
electro
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What are some ways to extend life of Nixie Tube?
I'm working on a Nixie tube clock and have read that nixie tubes have a life of about a year.
Does anyone know of ways to extend the lifetime of a tube?
Can you use a mosfet to switch the high voltage power supply using PWM or would that just end…
Shubham
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How are very long component lifetime claims ascertained/evaluated?
Its a common specification for household devices such as lightbulbs. However, I can't figure out how you'd truly evaluate/prove such a claim without running the device for the specified amount of time.
Consider a lightbulb that is said to have a…
midnightBlue
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Leaving the heater of a vacuum tube on all the time vs cycling it
I want to build a tube amplifier that will be on for ~7 hours/day. I was wondering whether the life expectancy of the tube would be higher if I left the heater on all the time and just turned the plate supply on and off.
The tube will most likely be…
Pentium100
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How deep should we discharge lithium batteries to maximise their lifetime?
Recently I posted an answer mentioning the very classic "lithium batteries like partial discharges, so design your system for limited depth of discharge". But then I wondered: with partial discharges, the number of charge/discharge cycles increases…
Mister Mystère
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Is my phone battery better / more capacitative than my laptop battery?
When we go out and look for phones, the first thing I do I always look at the battery capacity, usually 2000 mAh, 3000, up to 10000 mAh for a (external?) battery.
Looking at laptop batteries, they are much much larger and have only afraction of…
Gizmo
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