ฝัง
- เผยแพร่เมื่อ 28 ก.ย. 2022
- 40V 30A Adjustable Switching Power Supply (DC to DC Buck Converter, DC to DC Step Down Converter)
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Altium Designer + License (Free): www.altium.com/yt/myvanitar
OctoPart: octopart.com
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Article: www.pcbway.com/blog/technolog...
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Other Videos: bit.ly/2N9OlPa
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A DC-to-DC converter is one of the most commonly used circuit topologies in electronics, especially in power supply applications. There are three main types of DC-to-DC converters (non-isolated): Buck, Boost, and Buck-Boost. Sometimes a buck converter is also called a step-down converter and a boost converter is also called a step-up converter. A buck converter reduces/steps down the input voltage while increasing the output current.
In this article/video, I introduced an adjustable buck converter circuit that can deliver up to 30A and handle up to 40V at the input. The output voltage is adjustable from 3V to 37.5V. Several PCB design rules were followed to enhance output stabilization and current handling, also to reduce the radiated emission, and noise figure.
To design the schematic and PCB, I used Altium Designer 22 and the electronic search engine (octopart) to easily and quickly collect information about the necessary components. To get high-quality fabricated boards, I sent the Gerber files to PCBWay and finally tested the current handling, output stability, and noise figure using the Siglent SDL1020X-E DC load, Siglent SDM3045X multimeter, and Siglent SDS2102X Plus oscilloscope. Just build one and have fun!
Specifications
Input Voltage: 6-40VDC
Output Current: 30A (max continuous, See text)
Output Voltage: 3-37.5VDC Adjustable
Output Noise: 50mVpp, 4mVrms (18A load) - วิทยาศาสตร์และเทคโนโลยี
40V-30A Adjustable Switching Power Supply
You're great MyVanitar. 👍 I enjoy your videos so much.
Thank you so much 😀
any other channel I watch, just test power supplies with a Lamp! but you use equipment and no question or any doubt remains. This is a nice tight regulation. the output is very tame :-)
Wow, thank you!
Very very good job!!!
Thank you! Cheers!
Nice video ! The buck converter is very well designed, congrats ! Btw you didn't add the article's link yet ?
Thank you. definitely, It will be added soon. check back again later.
Great video.Thank you
Could you add more details about toroid cores? what is part codes or manufacture codes also what is AL value of cores .
Also what is wire thinknes and count number I know 5 paralelel 1 mm thicknes for big toroide but how much meter?
Thank you for design
because you are not bounded to exactly use them. if your cores have bigger height, doesn't matter, even better. the big one is T201-52 from Micrometals, Inc, and the smaller one is T130-52. you can use other manufactures, with the same size.
Your UC3843 switching controller has is ISEN pin connected to ground. Generally current mode controllers do not produce any ramp internally but measure the inductor current to obtain a ramp for PWM generation. Alternatively the UC3843 timing capacitor ramp can be coupled into its ISEN pin, as shown in its datasheet.
I recommend you to check your contrtollers' PWM output. Due to the lacking ramp waveform it is likely not a nicely regulated constant duty time when a constant load and a constant supply were connected. Should you have problems with dynamic loads you may also add a parallel capacitor to the compensation network (R1)
That's for a different purpose and I had tested it before. This works constantly and my setup allowed me to test up to 18A. constant supply and constant load. Build and test yourself
Even it passes the step response test which I'll show in the next video probably
What is the reasoning for bigger clearance with high current traces/polygons? Can you link to this IPC standard you talked about?
This is one calculator for this, enter 30A and peak voltage to 38, see the last row for the external traces: www.7pcb.com/trace-width-calculator
@@MyVanitar I am not asking about the size of the copper tracks, I am asking about the clearance between the copper tracks and ground. At @5:44 in the video you point to the difference in clearance length between signal traces and high current carrying traces. And you said at @6:05 that this is the IPC standard. So I was asking for the reasoning / explanation for this larger clearance and which IPC standard you are referring to.
man, as I told you the last row of the calculator gives you the minimum clearance between tracks (0.8).
@@MyVanitar I understand. However I was looking for an explanation for the increase in clearance length, as in the video it sounded like you had a specific reason and you read that somewhere in an IPC standard. So I was just curious where you read it or just in general your thoughts about why the clearance needs to be bigger. If you don't know or misspoke then just say that. its okay not to know things
You use two power supplies at the input, one for pwm and driver (uc3843, ir2104) and the other for switching, is it possible to use just one in combination with a minimum input of 15V to get 12V for pwm and driver regulation (uc3843, ir2104) for example using a zener diode and an NPN transistor?
You can do that, 12V input is not something special, you can inject from any source because the input and 12V grounds are the same. but 12V should be fixed and regulated. Please check the article. I will provide the link in the video description soon.
The limitation of your suggestion as you said is for when the input voltage is below 12V, which I had to cover in my design, but this is not your case since your minimum input is 15V
@@MyVanitar many thanks sir
How about making it digitally adjustable? Or even with an analogue input or PWM?
the resolution and step size matter, I should work on that, but who sponsors my time, whenever I had time, I will publish something.
@@MyVanitar I've got the same problem with being too busy. I'm using a "cheap" DC/DC with digital interface, for a cathodic protection project. But it has a strange behaviour where on power on, it briefly produces a short (I forgot where), so I'm using a relay to isolate it temporarily. I've been looking at designing my own for a while, but power electronics isn't my forte.
Does it short the output even without any connected load?
@@MyVanitar No, it was something like shorting one of the output lines to one of the input lines. It wouldn't matter if the output is isolated from the input, but I'm sharing the ground.
i want to try it bro .. can you please share design files
I will publish the article soon where you can read more details or even order the PCB
@@MyVanitar thank you :)
Now all Indian amateurs - can you share your design 😂😂😂
hahaha, Yeah, exactly. They asked. check other comments. I think they just check 15 seconds of any video
Not all Indians amateurs came here to ask you... guide them, make a path for them, it's ok if don't want to share. Afterall, every human being is amateurs until they prove themselves better than the others. 😁😁
first, his comment is just a joke and for fun, second, his point (and mine) is that some visitors don't even invest some time to watch because they are impatient, mostly they are amateurs. I hope this solves the misunderstanding.
Yeah, i got you. Btw nice video 😊
@@MyVanitar I believe 15 seconds are enough to get the general concept of buck converter from your video