Which AC-DC PCB power supply to choose


I’m currently working on a project which requires a AC-DC 5V power circuit to power my max 2W load consisting of an ESP32-S2, one 28BYJ-48, and one PH probe.
So I was searching on DigiKey, Mouser and Aliexpress for a AC to DC converter which can be soldered onto my PCB.

The following three power supply units are now on my shortlist:

I have the following questions:

  1. which one is the most reliable/safest?
  2. can I trust the HLK power supply?
  3. the LH05 seems to bee the only power supply with a good datasheet, or does the IRM-03 really not need any additional components such as a MOV or fuse?
  4. is there some other good option available? (preferably below 10€ and “easy” to by in germany)
  5. which one would you choose and why?

I’m grateful for every answer :smiley:

PS: I’m also searching for a good relay for an 230V 10A load ;D

Hi einsteinli,
welcome to this friendly forum!
This forum is intended to discuss things related to KiCad, so other forums like microcontroller.net
are the ones you should consider to see.
To answer your question:
YOU determine what you need! We (at least I) cannot figure that out for you.
My advice:
Visit a well known parts dealer, like RS, Mouser, digikey. I prefer Mouser.
They offer a really good parametric search. Needs a minute to get familiar with, but it’s worth the effort.
They generally do not sell crapp, so if the specs fit your needs, the part will be OK for you.
There is a datasheet in every parts describtion, you will have to read that to find out if external parts are needed, temperature derating and 1000 other details.
Next you could find out where to get the best price.
One more: meanwell and Traco offer a lot and relible parts relatet to power supply.
The same applies to relays: “good” is what fits your needs.
Have fun exploring the world of billions of parts!

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For supplying DC power to gizmo’s like ESP, Arduino, Pico… etc:
• for individual gizmos up to 9vdc, I often use typical Wall-Wart USB supply’s (5 to 9vdc)
• for up to 24V, 8A, I use these
• for Bench Power Supply, I’ve used several and these day’s, buy them on Amazon (example here). Look at user rating’s
• for Gizmo’s I design, I usually use LM7806 (for the 5vdc) - very inexpensive and ubiquitous (could use LM7805 but, I prefer the extra Voltage to cover any drops). Example (screenshot) of a recent circuit I made using the 24V, 8A unit to power the 7805’s (actually, the real hardware uses 7806 but I didn’t update schematic… I just reach into the bin and grab what I want…).
The Output voltage is Clean so, I don’t bother with Caps for cleaning them…

And, as ‘marera’ said, this isn’t the site for digging into design questions…


While we like to welcome new members, as @marera has mentioned, we try and restrict our conversations to topics relevant to the actual Kicad software and not general electronics questions.

If you are asking basic questions about mains powered power supplies, you need to check with someone who understands exactly what you need. This is a safety issue

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