Why are laptop chargers so small?

Question

Electronics

Previously, laptop chargers were healthy, but now, I noticed that almost all of them are comparable in size to smartphone chargers. What made this miniaturization possible?
I seem to be missing something in this life. Some new technology? New materials? Something third? What's the secret?

Answer 1

There are several reasons.
Firstly , the laptops themselves, on average, have become less voracious, they heat up less, and they need weaker charging.
Secondly, the elements are being improved, and ever higher frequencies are used in PWM. If earlier there were 40-60 kHz, then they began to use them at 100 and 150 kHz, and now at 500 kHz or higher (I won’t say for sure which ones they put in the new ones). And higher frequencies make it possible to reduce the size of pulse transformers and chokes. Plus, power elements become smaller and operate at much higher frequencies and at the same time heat up less - accordingly, they need a much smaller radiator (and sometimes they don’t need it). For example, a typical N-channel field-effect transistor (in a fashionable way, MOSFET) in the early 2000s is 10x10x4mm in size and for a voltage of 30V, a maximum current of 10A (30 per pulse). Now it's 3x3x0.5mm, and it's inside two transistors and PWM at once. With the same 30V input voltage, and output currents up to 10A. Or, 4x4x1mm, one transistor, 30V, 80A (!), and up to 120A per pulse.
Thirdly , they try to save money everywhere, just to meet the guarantee (or even less so that it works, because it is still necessary to prove that the warranty case is difficult for a power supply unit). Therefore, they put less capacitance of capacitors, simplify or remove some of the protections, make a thin, weak case. And for the case, which is immediately plugged into the socket, this is the easiest - after all, it is the pin of the plug that will break under load, and there is no smell of any guarantee here. And stepping on it will not work out very well, unlike the old power supplies that just lay on the table / on the floor / hung on a wire.
At the same time, the price for the old one is about 1500 rubles or higher, and for the new one it’s about 500 rubles, and no one will especially repair it, except to solder the wires or replace the capacitor - and it’s more profitable for the manufacturer, because. buy a new one, not take it in for repairs.

Answer 2

Prots in laptops began to eat less, due to slowness.