Small alternative to bench PSU

I can't justify a conventional bench power supply. (size / cost / amount of usage / etc)
Does anyone have anything good to say about something like this for powering small, low powered, projects?

They are inexpensive.


If you go this way, check it out well before you rely on it.

The pots/switches may be best removed and replaced with more convenient for your fingers.
Check out the short circuit protection capabilities.
Check out heat dissipation.
A ferrite bead on the output may help reduce switching noise.
Make sure the input supply to the converter doesn’t limit the converters capabilities.

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Yeah, usually modules like these work pretty well, in fact. No, not great if you actually hook a scope up to them and start measuring the noise, as they're usually somewhat noisy. But most digital Arduino-type circuits don't suffer much (or at all) from such noise.
Another caveat is that the maximum ratings are never very reliable. If they say 3A, then that 3A usually means "3A provided that the input voltage is between x.xx and y.yyy and output voltage is between a.aa and b.bb and additional cooling is provided for, and...etc.etc.". If you interpret it as "3A really means you can safely draw 1.5A and anything more is a bonus and should not be enjoyed for longer than a minute or so", all is well.

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An inexpensive self contained power supply:
≈ £ 90
https://www.digikey.ca/en/products/detail/stan-rubinstein-assoc.,-inc-dba-sra-soldering-products/KD3005D/10709902?utm_adgroup=Equipment%20-%20Power%20Supplies%20(Test%2C%20Bench)&utm_source=google&utm_medium=cpc&utm_campaign=Shopping_Product_Test%20and%20Measurement_NEW&utm_term=&productid=10709902&gclid=EAIaIQobChMIkISbnO308gIVQgnnCh25LgYvEAQYBiABEgKfFPD_BwE

What to you have to power (or think you might power). Could you use a 5V wall plug in adapter then a 5V to 3.3V voltage reduction board? There are a number of voltage / current displays.

with the board you asked about you would still need a battery / powersupply.

I have been pretty impressed for the price with a zk-4kx
btw - an old laptop PSU makes a good supply for use with one

Have a look at second hand units ?

If this is for Arduino type projects you could make something yourself with either fixed or variable output ( buy transformer etc etc ).
Batteries are another thing worth looking at , or a couple of wall warts ( say 5v , 9v ) ??

I’d be wary of cheap units available on the internet buy good , buy once

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Something good to say, they work! I tried it and got tired of looking for the screwdriver to change settings. By the time I had the RAW DC power supply, cables etc I was at just a little under what I could purchase a used lab power supply from my favorite online bid for it or purchase it supplier. I found this for you on the uk ebay site as an example of what to look for: Skytroniic 650.676 Lab DC Adjustable DC Power Supply 0-30V 0-3A | eBay
I am not sure if that is in your price range but they have others as well.

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Thanks all.
£90 is more than I can justify, but maybe a second hand bench PSU would be affordable. (I hadn't thought of that.)
That said, they're still inconveniently bulky for my situation.
I'll try a little one and see how it goes. :+1:

I don't know much about power supplies when it comes to the cheap ones, but I have a small unit that I got from ebay for about 10 GBP. It looks like this:


It takes around 7-36V in so perfect to run off an old 19V laptop brick power pack. I think the output is variable in 10mV steps from 1.2V up to 32V (assuming 36V in I guess). I don't know how noisy it is but it works fine for running my 3.3V and 5V Arduino projects.

Do a Google search for a ZK-J5X and they should appear.

An old desktop computer PSU can provide 12V in the 10A+ range. They also have rails for 5V and 3.3V (usually for hard drives, DVD-ROMs, etc)

What are you going to power it with ?

Now an ATX psu is something I hadn't thought of, but I might even be able to one for free.

If you do make a bench top ATX psu, add a reasonable sized fuse to 5V.

Example 2 Amp.

And/or a current limited output.

Think I’ve seen on eBay a facia for old computer power supplies with terminals etc and accepting the standard psu connector .