I am designing a PCB for a project with an Arduino Mega, it controls 4 relays, a 4" TFT screen, 3 temperature probes, 2 flowmeters, push buttons, etc... Initially I made a prototype with a linear voltage regulator, the The problem was that it overheated excessively, since the output has a fairly high intensity, approximately 1.5A, and the voltage drop across the regulator is considerable, from 24V to 5V. Now I'm trying to put a switching regulator, now that supports greater intensity. I am not an expert on this subject, and it would be of great help if someone could advise me if the design is correct, or could be improved.
If more information is needed, I would be happy to provide it.
It looks like the example circuit for the LM2596 5 volt fixed version ( with inbuilt feedback voltage divider) from the data sheet: https://www.ti.com/lit/ds/symlink/lm2596.pdf
The physical layout of the board is important and a specimen appears also in the data sheet.
An alternative to designing your own is to use a ready made buck converter and mount it as a daughter board on the main PCB.
I have already looked at the datasheet, but my problem is that I am not an expert in electronics and I have a lot of problems to understand it, so I was wondering if any expert could tell me if the configuration is correct
Thanks
I have managed many specialist switch mode power supply engineers in my time, and have never come across one that can make a switched mode power supply fully work in less that three attempts at the layout.
Which means you have zero chance at getting this to work correctly. Your best bet is to buy one, and not from a Chinese suppler, because those are rubbish. Choose a proper component distributor like Farnell (Newark), RS, DigiKey or Mouser.
By correctly I mean under all load conditions from the lightest to the heavyset without it bursting into oscillation. That of course means you will need access to an oscilloscope and have the knowledge of how to use it.
Thank you very much for your point of view, but could you tell me if you see the diagram I sent as correct?
According to the data sheet, that design will provide up to 3A at 5V with input voltages up to 40V.
So it will meet your requirements.
However I would change C2 to a 330uF 35V capacitor as specified in the data sheet.
Do you not understand? The diagram is the very least of your worries.
It is bog standard date sheet diagram. In essence it is correct, but you need to know way way more than that. Do you even know the type of capacitor C2 is? For example what sort of ESR it needs. I bet you don't even know what the ESR of a capacitor is.
That inductor L1. Do you know what sort of core you need on it? This can make all the difference between it working or not. And as I said the layout is hyper critical.
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