Do any of you guys know any online courses, (free or fee), that are designed for beginners to learn the process of how to design power supplies for delicate audio circuits as well as LED lights etc? You're probably thinking, "Dude... there're 500k videos on YouTube about it" That's true, and I have watched most of them. However... the majority of "DIY Power Supply" videos are about bench top power supplies for analysis of other circuits as you design stuff. That's not what I am after.
I recently built a super bright LED panel light for photography and video lighting. Sure, it was no big feat of science, but it was the first project I've ever built quasi from scratch. I used an off the shelf PS and a small dimmer board from eBay. The power supply that was rated for 12V with a max of 10A. As a test, I left the light panel on for ~half an hour to see if it would... I dunno... explode, melt, flip a breaker...? Sure enough... after half an hour or so, started to turn itself on/off at about a rate of once per second. When I touched the plastic power supply box, it was so hot, it literally felt like the plastic was softening from so much heat.
I did the math; there was no way my LED strips (wired in series OR parallel) could have been reaching even 5A, much less the 10A max current draw of the power supply. They are standard run of the mill 12V LED strips; the whole 5 meter strip doesn't go over 5 amps, and I only used about half of the strip. I read online that cheap oversees power supplies are sometimes garbage that may say 12V, 10A, but achieve no way near those values in reality. I have a really nice BK Precision 388B multi-meter, but... as embarrassing as it is for me to admit... I don't know how to use it to test the max capabilities of a DC power supply adapter.
So, I've heard terms like... switch mode... linear... and flyback topology... etc. but... I'm looking for a real resource or class that will explain to me, like the newbie I am...
I recently built a super bright LED panel light for photography and video lighting. Sure, it was no big feat of science, but it was the first project I've ever built quasi from scratch. I used an off the shelf PS and a small dimmer board from eBay. The power supply that was rated for 12V with a max of 10A. As a test, I left the light panel on for ~half an hour to see if it would... I dunno... explode, melt, flip a breaker...? Sure enough... after half an hour or so, started to turn itself on/off at about a rate of once per second. When I touched the plastic power supply box, it was so hot, it literally felt like the plastic was softening from so much heat.
I did the math; there was no way my LED strips (wired in series OR parallel) could have been reaching even 5A, much less the 10A max current draw of the power supply. They are standard run of the mill 12V LED strips; the whole 5 meter strip doesn't go over 5 amps, and I only used about half of the strip. I read online that cheap oversees power supplies are sometimes garbage that may say 12V, 10A, but achieve no way near those values in reality. I have a really nice BK Precision 388B multi-meter, but... as embarrassing as it is for me to admit... I don't know how to use it to test the max capabilities of a DC power supply adapter.
So, I've heard terms like... switch mode... linear... and flyback topology... etc. but... I'm looking for a real resource or class that will explain to me, like the newbie I am...
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