How do electronics eventually break? Do the connections on the motherboard get weaker or thinner over time?
In: Technology
One thing that wasn’t mentioned is connections on a silicon chip degrade due to electromigration. Basically electrons can hit atoms, causing them to move. This can cause a connection to fail or short on the silicon die itself.
There are many different ways that electronics can fail. If the electronics experience a significant amount of shock or vibration, that can cause connections to weaken or break. Some components age and fail, such as electrolytic capacitors. Some components are sensitive to overheating, overvoltage, or just in general having the power be out of spec. Solder (especially lead free solder) can develop tin whiskers that cause short circuits. And there are numberous other ways.
Sometimes solder connections aren’t very strong, and they corrode slightly, which breaks a connection. Sometimes (if it’s an item that sees temperature or humidity fluctuations) the environmental fluctuations will cause problems. There may be corrosion in power connections, there might be physical failure of an electrical connection from expansion and contraction…
Sometimes individual components will fail. Electrolytic capacitors can fail, because they’re complex for their size (layers of foil, insulators, and liquid parts).
As electronics get smaller, their power demands decrease. The electrical paths (wiring, circuit board traces, and the internal traces in integrated circuits) are smaller by _a lot_ than in 1980s electronics. Older electronics were more robust, but required more power.
The delicate nature of more modern electronics can cause them to fail in ways that aren’t apparent, since variation in electronic components may happen inside an integrated circuit, or somewhere invisible to the user.
Time, environment, and random chance make a difference.
I have a GPS unit in my car that is actively dying, and the circuits that provide the information are fine. The display, however, is losing contact with the circuit board. The connections for those are often a conductive rubber strip, adhered to the contacts of the display. I can squeeze the sides of the GPS and the map displayed clears up, but it’s clear that the age of the GPS is there. It’s fallen off my windshield a lot, which seems to have loosened a lot of connections.
There can be different causes of failure. The circuit board will usually have exposed copper and tin which will over time corrode and wither away disconnecting the components from each other. Tin is also quite brittle so if the device is dropped the tin might develop cracks which after repeated drops can go clean through the connection. A similar thing can happen to the circuit board itself. If you drop it the force from the mountings to the components will go through the circuit board which can cause it to crack. These cracks can sever vital traces and prevent the electronics from working. But the chips themselves can also stop working for various reasons. They are made of different materials which can expand at different rates when the temperature changes. This may cause tiny cracks that eventually cuts a wire inside the chip. Transistors may also wear out with use. This is especially noticeable with the transistors used in flash memory as they can be permanently damaged after just a few thousand write operations.
Electronics can suffer physic damage such as being dropped or banged which can damage the parts. One of the most common problems is damaging the power outlet connector because the adapter sticks out from the machine so it’s more prone to breaking the connector.
Many electronic devices have physical moving parts like fans and motors that wear out with time.
There’s also environmental factors. Electronics do not like heat and the accumulation of dust will cause parts to overheat in time, which can cause solder joints and individual electronic components to wear out.
Oxidation is another problem. Rust can accumulate on the parts causing corrosion damage and an oxidation layer can block electrical contacts.
Well, there’s a lot of reasons they can break but the most common ones I’ve come across are bad capacitors. They’re devices designed to temporarily store a charge or smooth out current. Many of them contain an electrolyte, a conductive, often acidic goo that can leak out overtime and cause corrosion that damages electrical connections on the board. Or sometimes they just pop and release the “magic smoke”. Or in the case of a lot of really old components, they can degrade and internally short circuit, which cause cause a chain reaction that damages other components. Which is why you shouldn’t turn on a vintage radio without checking the caps first, as these shorts can damage the vacuum tubes. Particularly the rectifier tubes used to convert AC to DC current. It’s not always easy to replace those components versus just replacing old caps with modern ones.
Vacuum tubes go bad due to air leaks which cause internal components to rapidly oxidize and burn out. They can also die due to contaminants in the manufacturing process leaching out. Overheating and electrically overloading tends to kill transistors pretty quickly.
OK – lets set some expectations. Industrial electronics will last 20 years or more and work nearly 100% of the time when they are being used. That is a hell of a record for any machine, as electronics are still simply machines. So yes, the circuit boards can get rickety but a well constructed one will last forever, and I am not joking about that they just don’t go bad nearly as often as we give it credit for. I ran a phone system (an Avaya with MaBell scratched off and Avaya penciled in) with massive digital cards that were installed in 1993 and they lasted until the phone system was retired in 2013. The system had never been rebooted.
That is best case scenario, the electronics are robustly made and are in environmentally controlled areas. If the magic smoke (look it up) escapes, it is usually because a meatbag spilled water on it, plugged the wrong kind of power into it, or dropped it. Occasionally a surge will happen from grid power, that normally blows up a power supply instead of the circuit card itself. I have replaced electronics that were hit by lightning, I don’t care if you have the grounding cable properly seated and the power supply is designed to fail open, that much static electricity will blow up the circuit card.
So, barring the obvious, the issue is normally not with the circuits themselves, it is with the software programming. Simple programming lasts forever, complex programming eventually breaks down if it isn’t patched. There is a term for this in CS called ‘software rot’. Think of it as entropy specific to software. Without modification, eventually the code will rot out. If it is simple it will last a lifetime, the more complex it gets the more likely to suffer this entropy.
Latest Answers