Eli5 Why does heat slow down electronics?
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It doesn’t or at least not directly, it’s electronics that are intentionally designed to slow down as they heat up, because CPUs can generate a lot of heat, and if you don’t cool them down enough, they can overheat and fail, which is rather undesirable
Too much heat *damages* electronics. When modern computers and phones get near a dangerous temperature, they slow themselves down on purpose to avoid producing more heat so they do not get so hot that they are damaged.
On its own heat does not slow down electronics. It has some negative effects on some types of electronics but screens and batteries may be more effective at high temperatures. However extreme heat will damage all types of electronics (just like any item) so we artificially limit the use of hot electronics for protection
If it does depend on the electronics. CMOS transistors do get a bit slower because of how electrons move in the warmer material. Bipolar on the other hand gets faster. For most other components there is a not significant change. Resistance in wires does increase with temperature and it can have an effect. But this is not something that has a practical effect for almost all consumer products, you need to do extreme CPU overclocking for it to start to be relevant.
The main reason that computers and phones have reduced performance when warm is that the speed is intentionally reduced. It is not because they can’t operate as fast it is to stop them from getting too warm and avoid physical damage.
So the clock speed is reduced so the temperature in the chip does not get to high.
The efficiency of a cooling system depends on the temperature difference between the hot and cold object. So the rate of heat leaving a phone or computer is reduced if the surrounding air is warmer. The rate of heat can be removed from the device is often a limiting factor for the performance of the system.
Compare that to if you do physical work a warm vs cool day. You will get too hot a lot faster a warm than a cool day.
Heat won’t slow down electronics.
Excessive heat can damage them. Most electronics will deliberately limit themselves if they sense getting too hot to try and prevent overheating & damage.
Electronics slow down themselves down intentionally to prevent heating up too much, because heating up too much would break the electronics, permanently.
Silicon (the stuff in CPU’s) can destroy itself through thermal runaway.
As more power goes in, the hotter it gets, and it can take even more power, and get hotter, and take more power.
Eventually it will take enough power to destroy the circuits on the silicon.
[https://en.wikipedia.org/wiki/Thermal_runaway](https://en.wikipedia.org/wiki/Thermal_runaway)
The complete model for transistor behavior has the temperature variable all over the place. It even has a T^3 in one place. So, electronics operate outside of expected performance. When the temperature is too high or too low. Designers simulate temperature changes and validate performance up to and down to some temperature. Outside of that, things don’t work as they should. So, safety circuits are used to either slow the system (and thereby reduce heat) or shut the system down. your car and your iPhone both shut down for protection at high temps. Computers slow down first.
to be clear, it could be that in some cases the circuit could work better at high temperatures IF that was what it was designed for. But people design for nominal earth temperatures, so higher temps are outside of the design window.
My iPhone gets slow in the uk in a hot day what about countries that are constantly hot? Do they sell different iPhones for the climate?
Run a processor too hot and it can lock up and even damage itself. Hence liquid cooling systems.
In big data centers they blow cold air up from vents in the floor.
So is then goblal warming the solution to the robot uprising? Haha
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