power for control circuits in high voltage applications

How do they obtain low voltage (5V/3VDC etc) for control circuits, in high voltage (220VAC) power applications in professional products?

Generally, with a separate power supply, the so-called "housekeeping" or "auxiliary" power supply. It can be a switching power supply or a more traditional one.
In high power switching power supplies, there are very often auxiliary supplies, too. Their only job is to provide power for the control circuitry, having nothing to do with the output. This is so because the complexity may require it and the added cost is only a small percentage of the total cost.

Actually i don't want to use linear ones because of the size. But i don't have any experience with the switching ones. So i don't want to spare time with designing it. What is the easiest way to make one? I need ready components or designs for
220VAC in, 5VDC@1A out. Also it musn't be very expensive as there ready dc/dc converter blocks which are very expensive (several tens of dollars).

probably for a cost effective solution you should do yourself...
there are several ICs to make low power low cost power supplies....they have internal mosfet and have a few pin count...
like top switch, tiny switch....
probably you can find an application note how to make something like your needs with those chips....

If volume of circuit is not important for you u may use a PC power supply for your need.
Thanks

atmaca said:

If volume of circuit is not important for you u may use a PC power supply for your need.
Thanks

Click to expand...

I'll embed it in a design so i need a seperate one.

Added after 3 minutes:

olemp said:

probably for a cost effective solution you should do yourself...
there are several ICs to make low power low cost power supplies....they have internal mosfet and have a few pin count...
like top switch, tiny switch....
probably you can find an application note how to make something like your needs with those chips....

Click to expand...

Sure i'll do myself but there musn't be a real design task. A product with a reference design which is low cost and needs low external components is ok.

seyyah said:

Actually i don't want to use linear ones because of the size. But i don't have any experience with the switching ones. So i don't want to spare time with designing it. What is the easiest way to make one? I need ready components or designs for
220VAC in, 5VDC@1A out. Also it musn't be very expensive as there ready dc/dc converter blocks which are very expensive (several tens of dollars).

Click to expand...

May be you can consider to use offline controller from On Semiconductor (e.g. NCP1200 https://www.onsemi.com/site/products/summary/0,4450,NCP1200A,00.html )
You can find few reference designs (with complete component lists, e.g. part#) at NCP1200 page.