The most important part of any electronic device is the power supply section. Any instability or malfunction in this part causes the device to stop its operation or show weird behavior. In this article/video, I introduced an AC to DC Flyback Switching power supply that converts 220V-AC to 8V-DC, which can be used in a variety of applications.

The 8V selection for the output makes this supply friendly for any type of linear regulator.

The maximum power delivery of this power supply is 24W, which means it can handle 3A at 8V output. The controller chip is DK124, which does not need any external supply, a startup resistor, or even an auxiliary winding on the transformer. The transformer's ferrite core is RM8, which is different from most supplies that use EE or EI cores. A small potentiometer allows you to adjust the output voltage and set it to 7.5 to 8V.

More details check here:

https://www.pcbway.com/blog/technology/220VAC_to_8VDC_24W_Flyback_Switching_Power_Supply_88bf6837.html