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2021-01-15 10:27 pm
Learn about voltage regulators and buck converters that you can use to power up your electronic projects.
Full article at https://dbot.ws/pwrvolt
Today we are going to look at the somewhat mundane but absolutely essential subject of supplying power for your electronic projects. Trust me, this stuff is important!
Electronic devices typically require either 5 or 3.3 volts, sometimes both. Other common voltage requirements include 6 and 12 volts for motors and displays. Some complex designs (ie. a robot) require several different supplies with different current capabilities.
When you build your latest robot or IoT device you’ll need to consider how you'll supply these voltages in the real world. On the workbench you can use a bench power supply if you have one, a USB adapter, or even the USB port on a computer (just like with the Arduino).
But when your creation needs to exist on its own with a line-powered or battery power supply you’ll need to figure out how to get all of those voltages delivered to your components, preferably easily and inexpensively.
I have nine, yes nine methods of doing exactly that. Today I’ll show you a number of different voltage regulators and converters ranging from the classic 7805 3-pin voltage regulator to a tiny device that can supply a steady 5 volts even when your battery is about to die.
Check out the following Table of Contents to skip ahead to the power supply solution of your choice. Or just sit back and enjoy the show.
INTRO
00:00 - Introduction
03:00 - Breadboard power supply module
06:28 - Power Supply Basics
LINEAR REGULATORS
11:42 - LM7805 - 5 Volt linear regulator
14:32 - LM317 - Variable linear regulator
17:52 - PSM-165 - 3.3 Volt linear regulator module
19:47 - AMS1117 - 5 Volt linear regulator module
21:43 - L4931CZ33-AP - 3.3 volt low voltage-drop regulator
VOLTAGE CONVERTERS
23:51 - Buck Converter Intro
24:41 - MINI-360 - Variable buck converter
26:46 - Boost Converter Intro
27:37 - PSM-205 - USB boost converter
29.07 - MT3608 - Variable boost converter
31:06- Buck Boost Converter Intro
33:06 - S9V11F5 - 5 Volt buck boost converter
That last module is the one I was referring to earlier, it really is an amazing device and is perfect for your battery-powered projects.
As with all of my videos, there is an article at https://dbot.ws/pwrvolt Now go power something up!
"Never trust a computer you can’t throw out a window." — Steve Wozniak
2021-01-23 12:10 pm
One of the best videos in this channel. 😎
Thanks for pointing this out. It was a good refresher and, for me, an education on some new stuff.
If your code won't compile, have another glass of bourbon. Eventual the problem will be solved.
2022-02-03 11:06 pm
I've been blabbering over in the YouTube comments and thought this might be a better forum.
I'm having trouble understanding the capacitors on the 78xx series regulator. I'm wondering if I could hook one to a scope with and w/o caps and understand their effects? I ask because, the last time I hooked up a scope was in my college EE lab and I blew a circuit breaker!
Are the caps used to smooth out the transistor switching? I'm still at a loss at what they use to measure the output voltage! My linear mind cannot come up with anything that isn't proportional to input voltage. Is the BEC (battery elimination circuit) referred to in RC aircraft simply linear regulator. - Cheers!
2022-02-03 11:20 pm
The regulator uses feedback to do its job, but it's not fast enough in all cases. The input capacitor provides a reserve to prevent it from going into an oscillation mode.
The output capacitor helps provide a stable output buffering the possible variations in power in as well as power demanded.
Anything seems possible when you don't know what you're talking about.
FPVCurmudgeon reacted
2022-02-04 12:04 am
Thank you for the reply. I probably understand the feedback, which seems to be the voltage across the top resister, however, w/o the magic chip, that would be a simple fraction of the input and thus proportional to it. I'm at a loss how they come up with a reference that maps to the desired output voltage. I'm sure this isn't clear, but that reflects my confusion. I flunked most of my early EE classes and was rescued by E&M Field Theory, well, the math. lol
Inst-Tech reacted
2022-02-04 12:09 am
Maybe this will describe it better than I can ...
https://www.digikey.ca/en/maker/blogs/introduction-to-linear-voltage-regulators
Anything seems possible when you don't know what you're talking about.
FPVCurmudgeon and Inst-Tech reacted
2022-02-04 1:17 am
@FPVCurmudgeon, the voltage reference in a linear voltage regulator is called a Bandgap reference..it basically consist of a Zener diode shown in the attached
regards,
LouisR
LouisR
FPVCurmudgeon reacted
2022-02-04 1:28 am
Thank you! That will take a while to process. Great to have kindred souls to talk about this with! May save our marriage. 😀 🤣 😆
Inst-Tech reacted
2022-02-04 3:01 pm
@inst-tech Zenier diode, now that is a thing from my past, ran into Bode plots recently. I recall the names but that is about all. lol
Inst-Tech reacted
2024-10-24 6:00 am
Hi everyone,
I recently watched Bill's video linked to this topic as I was looking for a power supply board to incorporate into a project, namely to provide 3.3V supply for ESP32 boards and a separate 5V supply to power small servos (SG90 etc).
I was looking at the MINI360 buck converter, but when searching on Aliexpress, I came across a fixed voltage version, the MINI560, and thought it might be better than the 360, as Bill had mentioned the small trimpot to set the voltage can be tricky to adjust correctly.
Well I ordered some of the 560's, both in 3.3V and 5V and was hooking up a 5V one today to power some servos, and I've run into some issues.
As soon as the servo receives a signal from the ESP32 to operate, the MINI560 shuts down from what I'm presuming is an overload. Now, the specs on the 5V MINI560 says they are good for up to 3A, which I would have thought is plenty to drive one servo.
I have tried a few different servos, al with the same result. These servos have worked OK previously.
Just to prove it wasn't the servo, I connected it back up to my breadboard power supply (MB102) and the servo works perfectly.
So, I tried a second MINI560 and got the same result. It shuts down as soon as the servo operates.
Surely I could not have received two defective MINI560s.
Has anyone else used these before instead of the MINI360?
Cheers,
Ian
Ian Millard
Port Macquarie, NSW, Australia
ESP32/Arduino etc novice
2024-10-29 9:24 am
Hi everyone,
I recently watched Bill's video linked to this topic as I was looking for a power supply board to incorporate into a project, namely to provide 3.3V supply for ESP32 boards and a separate 5V supply to power small servos (SG90 etc).
I was looking at the MINI360 buck converter, but when searching on Aliexpress, I came across a fixed voltage version, the MINI560, and thought it might be better than the 360, as Bill had mentioned the small trimpot to set the voltage can be tricky to adjust correctly.
Well I ordered some of the 560's, both in 3.3V and 5V and was hooking up a 5V one today to power some servos, and I've run into some issues.
As soon as the servo receives a signal from the ESP32 to operate, the MINI560 shuts down from what I'm presuming is an overload. Now, the specs on the 5V MINI560 says they are good for up to 3A, which I would have thought is plenty to drive one servo.
I have tried a few different servos, al with the same result. These servos have worked OK previously.
Just to prove it wasn't the servo, I connected it back up to my breadboard power supply (MB102) and the servo works perfectly.
So, I tried a second MINI560 and got the same result. It shuts down as soon as the servo operates.
Surely I could not have received two defective MINI560s.
Has anyone else used these before instead of the MINI360?
Cheers,
Ian
If possible, try to test the two Mini560s separately.