Why do computer chargers need those big adapters? Why can’t you just connect the devices to the power outlet with a cable?
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Once upon a time you actually could. Of course, it was because the mains adapter was built inside your “laptop” [(i.e. a computer that barely fitted onto your lap)](https://imgur.com/a/dgJg9KH)
One thing most people aren’t covering, unless it has a motor that spins in it, chances are your device is modifying the AC in your walls to be DC at the device. Most products have discrete power supplies built into the device itself, or in the case of USB chargers and wall warts, they convert the power right at the outlet.
Fun fact, some low quality power inverters can produce an annoying hum.
They don’t need those bricks. They could put that piece into the laptop itself but then it would be much bigger and heavier all the time.
it’s the step down transformer in the adapter. your house outlet is 120 volts and your device is probably 12 volts or less. the physics of it does not allow it to be much smaller. it has two cores with many rounds of copper winding. the two cores don’t touch. the electricity is transferred via induction and stepped down from 120v to whatever you need. that’s why it’s usually external. it’s just too big.
in desktop pc’s you don’t have these adapters, bcs you have a power supply in the box, but in laptops it doesn’t fit so it’s located outside
Like a steam engine, the big piston works by allowing steam in either side alternatingly, pushing the piston arm back and forth. This is similar to how power works, a rhythmic cycle of push/pull.
Like the train wheel, the brick converts the back and forth motion of the pistons into forward motion only, moving the train down the tracks.
In computers, power doesn’t go back and forth, it goes in one direction, like the toy train on a track loop.
So the brick is the piston and wheel, converting the back and forth power of the wall into forward moving power for the ‘train’.
The parts needed to make this happen are bulky and take up room, so they make them a special place outside the computer so the computer can be small and thin for you, and not take up too much space like a big wall plug does.
In a desktop computer it’s inside and they call the special brick a ‘Power Supply Unit’, or PSU for short.
Saw a guy blow a presentation at work because his laptop died.
He thought it was an extra battery and he didn’t need to look for an outlet.
Tough time to learn that
Oooo I’m in an electronics class rn and we spent a while on this. More or less there’s a bunch of steps to change power from what works well for generation to what works well to power electronics and lights and stuff.
In power plants, there’s huge generators that turn and this rotation makes AC power. AC works much better than DC for long range transmission. Also, power lost due to “pumping” it over long distances like power lines is minimized if it is VERY high voltage and low current.
However, most devices use something like 5-12V and DC current. So to get that from the extremely high voltage AC to low voltage DC a few things need to happen. First is outside of the box, and a local station steps it down from power line voltage to your house and it comes out of your wall at about 110v if you’re in the US. It is still AC though.
Idk if you know what a sine wave looks like, but that’s how the AC voltage looks. Half of it is positive, half is negative before it repeats itself. The first thing that happens is a bunch of diodes (like leds but no light) act as one way valves and turn it all positive, almost like a bunch of McDonald’s arches. The problem now is that if you used this power it would flicker from bright to off, then bringht again.
So, the next thing that happens is a capacitor to smooth it all out. What this does is essentially scoop some off of the peaks and dump it into those valleys to even the whole thing out. It’s kinda like a buffer against too many highs and lows. Now it’s more or less a flat line with instead of arches it’s just a little ripple or wobble to it.
The last is some sort of a regulator that evens it all out to a constant voltage of whatever your device uses. There’s a few different ways to do this, which is why there’s different power brick sizes. However, the general idea is the same because the same steps need to happen.
Hope that helps, lemme know if you have any questions.
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