ฝัง
- เผยแพร่เมื่อ 28 มิ.ย. 2023
- 220VAC to 8VDC 24W Flyback Switching Power Supply
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Altium Designer + License (Free): www.altium.com/yt/myvanitar
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Altium 365: www.altium.com/altium-365
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OctoPart: octopart.com
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Article: www.pcbway.com/blog/technolog...
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Gerber/PCB Order: www.pcbway.com/project/sharep...
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Other Videos: bit.ly/2N9OlPa
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The most important part of any electronic device is the power supply section. Any instability or malfunction in this part causes the device to stop its operation or show weird behavior. In this article/video, I introduced an AC to DC Flyback Switching power supply that converts 220V-AC to 8V-DC, which can be used in a variety of applications. The 8V selection for the output makes this supply friendly for any type of linear regulator.
The maximum power delivery of this power supply is 24W, which means it can handle 3A at 8V output. The controller chip is DK124, which does not need any external supply, a startup resistor, or even an auxiliary winding on the transformer. The transformer's ferrite core is RM8, which is different from most supplies that use EE or EI cores. A small potentiometer allows you to adjust the output voltage and set it to 7.5 to 8V.
For the schematic and PCB design, I utilized Altium Designer 23 and shared the project with my friends for feedback and updates using Altium-365. The fast component search engine, Octopart, proved invaluable in quickly obtaining component information and generating the Bill of Materials (BOM). To ensure high-quality fabricated boards, I sent the Gerber files to PCBWay.
I tested the board for voltage drop and current delivery, output noise, and load step response. I used the Siglent SDL1020X-E DC Load, Siglent SDS2102X Plus oscilloscope, Siglent SDM3045X multimeter, and Siglent CP4020 current probe to perform all tests. I am confident that this circuit will meet your requirements for a compact and efficient power supply, providing reliable performance on your electronics bench. - วิทยาศาสตร์และเทคโนโลยี
220VAC to 8VDC 24W Flyback Switching Power Supply
First of all: Thank you very much for your very detailed explanation. I've been following your videos for a while. And this video is definitely one of the best!
A wish for the future: Could you record a video or write an article on how to calculate the number of turns and the inductance of the storage choke (transformer)? There are many ways to do this, I know. For example, Power Electronics offers software for dimensioning the storage choke. There is also a program for this calculation, the author comes from Russia, I think. But it would definitely be very interesting to see how you do it, how you dimension the storage choke.
You're welcome, thank you for your comment. I have a plan to make a practical course around this where you can easily follow and build whatever Flyback supply you like. I have not decided yet
Oh man, the way you test your designs, it's quite unique on all over the YouYube
Glad you like them!
Hello, thank you for sharing this, it was a lot helpful;) may I ask you please, what's the most advantage of using RM8? Thx
They are more efficient than traditional cores and less prone to saturation, so a smaller core can handle higher currents. also, self-shielding means they introduce lower EMI figures
how did you design the HF transformer? Through software or did you look for an off-the-shelf part that had the correct voltage and power specs?
I calculated it myself, It's very hard to find a transformer that matches the design specs. I explained how you can build one. I provide whatever information, but when I see you miss and just skip the content (which is clear from the question), I get very disappointed
Another solution is to ask the manufacturer of the controller IC for a suggested transformer. Many times they can provide you with an off-the-shelf part that will work in your designs.
hello, why the secondary winding does not rotate clockwise? thank you for this dedicated work.
it should not be clockwise because the polarity is in reverse
@@MyVanitar What is the reason why the poles are reversed? Thank you.
for the secondary, the negative line is up. you can wind and test it yourself. it's just 4 turns
Hi, what is the purpose of OC pin DK125 IC?
I have gone through the article, but there is no transformer design calculation, can you provide those informations?
OC pin is the same as the Drain of a Mosfet, where it switches the winding, regarding the information, I can not provide everything as a piece of cake, I'm sure you can't find any article/video with this level of details and tests anywhere
@@MyVanitar Sadly, my collection of chips does not include a DK125/Viper22a ... I do appreciate though, you are choosing very generic and inexpensive components. Aren't the transformer components the most expensive?
Yes, there are many components but when we can conclude something cheaper without sacrificing the quality, there is no problem. This SMPS chip is really cheap and works well!
Datasheet says 18w. are you sure it can provide 24w continuously without a heat sink ?
DK125 is 24W. DK124 is 18W
Can you curious if you did 5V instead with an embedded filter, can you go directly from SMPS to filter to MCU?(skip the linear regulator)
what can I say, in general, yes you can, but if you use an RC filter, it's good but causes a voltage drop and it is good for low currents, also any current change in the load, changes the voltage drop and causes voltage fluctuations. if you use an LC filter, the noise frequency might come close enough to the resonance frequency of the LC filter and increase the noise. The thing I mentioned in the video is what is used in good commercial devices. SMPS (like this design) is away from the main board in a metal enclosure and it is connected to the board with some wires, then some linear regulators or low-noise buck converters are used.
you can use a ferrite bead for high freq. filtering
don't forget to include some capacitors
Can you share me full step of the Altium Designer licence activation.
follow the link in the TH-cam video description, and register on the website with your Email. download the software and go to License section and activate your license
@@MyVanitar it is fully free of life time or not.?
do we need remake the transformer for 12V??
+/-1V is fine using that potentiometer, but for 12V yes. it's hard to find 7.5V-8V power supplies in the market, that was my motivation
@@MyVanitar thank you!
How to convert it into 12V 2A? Is there any easy method
it can be done with the same circuit, just the secondary winding and value of two resistors should be modified, but my intention was to build something that's hard to find in the market. if the need for a DIY for the 12V is high, I will design another one also
@@MyVanitar Thany you very much for ur reply . Yes I think 12V 2 A is much more required thing. It would be very helpful for us and for society. And as I can the voltage drop after full load is very less which is quite impressive.
if your need is 12V-2A continuous, you should use a supply with at least 2.5 to 3A output, for a long term run
@@MyVanitar Yes but for that we cant use DK125 as its max output is 24W. I have tested for continuous full load of 2A it works perfectly even for longer period of time .
This circuit is also with DK125, however even if it works I suggest you avoid using components at their margin. by the way, I put 12V-2.5A in my list for future publication