USB 5V 2A car charger how is it done?

Without a doubt, car charging is a useful thing.
I took a simple set of experiments to try.
The cable has already been tested previously.
redlightgreen.org/blog/aliexpress/28717.html
Charging is very compact and short - not every cigarette lighter socket is compatible with it, because may not get a central contact.




Charge naturally disassembled.



It consists of two soldered boards - getinaksovogo for the USB connector and fiberglass for the converter.
The installation quality is mediocre, the soldering is careless, the boards are soldered crookedly, but surprisingly everything works.
There is naturally no safety fuse
Charged based on HC8816 (2A, 4.75-25V, 350kHz)
The real scheme of the device.

Open circuit voltage up to 5.39V.
Under load on the connector itself, the voltage does not drain at all.
At the maximum declared current, 2A quickly overheats well beyond 100g and smells of singe.
More or less nominally without overheating, it keeps the output current up to 1.3A.
Although the declared operating voltage is 12-24V, charging cannot be included in the 24V on-board network, as there the nominal voltage is 28-29V and there are short-term voltage surges.
The minimum input voltage to provide an output current of 1A is at least 6V.
When installed, it looks like this


For comparison, I will show the insides of the Belkin 5V 1A auto-path
As the saying goes, feel the difference





The final conclusion is that this charge is best avoided.