Simple 5V power supplys use a transformer and a diode bridge followed by a linear regulator like in the picture. You get these for about/under 1$ from china. I wanted to integrate such a circuit into an PCB, but I am not able to find an transformer as cheap as these 5 supplys (I don't want to solder on one of these crap PCBs). All transformers I found cost over 1$. So I wanted to ask if this transformer like component is really called transformer since I'm not an native english speaker and don't find anything relevant.
EDIT: cause in the comments high currents are often mention I wanted to say that I only need some mA for low Power µController.
Also corrected the wrong circuit description (phone charger to simple power supply)