This is definitely one of the most useful tutorials I've watched so far. All my questions that nobody bothered to answer, explained in one simple video. Thank you very much!

@RalphBacon

6 жыл бұрын

So glad it helped you, Marl3x, that's why this channel is here! Thanks very much for posting, great to hear from you.

thanks again

@RalphBacon

5 жыл бұрын

You are most welcome Big Rick's Haberdashery, I'm glad you like the video. Nice to hear from you.

Very nice tutorial! I'm going through a bunch more of your vids and learning a lot. I have seen many other vid creators but you have a way of explaining the right things in the right order, without a lot of fluff words that add no USEFUL info. The differences between linear/switched could be a little better demonstrated rather then explained with a few ammeters on the input and output sides. Aiming a digital thermometer at the linear heatsink, and running it up past 2 A would show the practical meaning of efficiency. Also a scope on the output of the switcher and then the linear would demonstrate the noise aspects. Consider it for another vid when you have some spare (ha!) time. :)

@RalphBacon

6 жыл бұрын

I'm sorry, Jim, I didn't understand that last sentence. Spare and time? What does this mean? I believe I've heard of the phrase but I assumed it was fictitious. Anyway, thanks for your supportive words and the critique which I will look into in more detail but unfortunately time (that word again) has beaten me here as Benny is due his supper. Seriously, thanks for posting, appreciated.

@jimbarchuk

6 жыл бұрын

I edited my post slightly. I hadn't meant to put a -strike- through the word useful. That NEGATED the word!! I guess you understood my intent. Adding - or * adds strike but I can't figure out how to add a bold or underline. So I added caps which is good enough.

@RalphBacon

6 жыл бұрын

To add *bold* to a post, surround that word with asterisks. Doesn't seem to work for two or more words though.

Thanks. I'm needing to power both an arduino nano and a 12v motor off the same supply (which the arduino controls via a relay). While the nano will take a 12v supply, I'd prefer to give it 5v so that the nano is not having to manage the extra voltage. The buck converter seems perfect for this.

@RalphBacon

5 жыл бұрын

Yes, it makes sense to do it that way, Chris. Just remember you MIGHT need to clean up the output a bit (simple resistor and capacitor) to get rid of any high-frequency noise on the buck output. If you have a scope you will be able to check this.

I'm back at 7:43. It would seem Benny sounds a lot like Scooter, as I just got back from attempting to let him in the door, and he was no where near. Not that my ears are much good after aircraft, rifles, and test tones. :) (I'm slowly catching up on your videos. Every one thumbs up so far, and played start to finish.)

@RalphBacon

4 жыл бұрын

It's safe to say that the quality of production gets better as you move forward in time, but hopefully the content is consistently useful throughout! Benny sends his regards and wishes you happy watching!

Great comparison between linear and the Buck ! 73 N8AUM

@RalphBacon

4 жыл бұрын

Glad you liked this video, vidas, nice to hear from you!

Hello Ralph, thank you for your teaching tutorials. They help a lot. What about the Quiescent Current of each one, I have tested the LM7805 with 9v in and I get about 3.1mA consumption with no load. I haven't tested the MP1584 yet but according to it's datasheet it should cosume around 100uA with no load which is a huge difference when using batteries on our projects. Now I'm a little bit confused because the datasheet is for the IC and not for the buck converter board that use this IC. The 100uA quiescent current applies for the buck converter?

@RalphBacon

4 жыл бұрын

Linear voltage regulators will always use more current (eg a few milliamps) and are not really suitable for any battery-powered project. A simple buck boost (or DC to DC converter) will take far less but you don't get something for nothing. 100µA would be a good figure - but if your Arduino goes into Deep Sleep and consumes just 0.2µA (as I showed in recent video) then it still seems too much! It very much depends on how critical power consumption is in your project.

Hello Ralph great education video. Can you please do a video of linear effect hall sensor powering a 5v led strip of 1m. Powered by 5v. Or can you suggest any places where I can buy the ready made module.

@RalphBacon

6 жыл бұрын

You are in luck, Ajay. Video #55 describes a Hall effect transistor and using that as the sensor to turn on an LED. You could easily use this as a basis for your requirement. Have a look and see how it goes.

A good explanation and easy to follow. Is is possible to use a buck converter and linear converter in series to get a more efficient stable output? For example have a buck converter reduce 20v to 7, then a linear converter reduce that to 5? Or would the linear converter not react quickly enough to avoid the ripple?

@RalphBacon

6 жыл бұрын

You *can* use a linear converter after a buck converter, BaselBantam, (I've seen that quite often in commercial designs) although you would not want to drop from 20v down to 7v as the heat generated would be huge (with a correspondingly huge heatsink) and thus loss of efficiency. What I've seen most is a drop from 5v to 3.3v using a linear converter that doesn't require more than about 1v above the output (that is, you want 3.3v out so the input has to be at least 4.3v). Some linear converters require 2v above the desired output voltage, not so good. However, that all said, if all you're doing this for is "stability" or to reduce ripple then forget it. Whilst a switched mode power supply (eg from a buck converter) does contain a tiny high frequency element of noise / ripple it's hardly enough to worry us in day-to-day Arduino use (unless you're using a radio frequency transmitter, for example, when it *can* matter).

@smithjonathan

6 жыл бұрын

Ralph S Bacon Thank you. That’s a thorough answer.

There a number of ways to get the ripple voltage down to something manageable. One is to place a larger cap or two you could place the linear regulator on the output of the buck converter which would be set to say .01 volts higher than desired. Am sure mate there are more ways but think the second one is cheaper component wise.

@RalphBacon

7 жыл бұрын

Yes, TechMan1219, ripple can be bothersome, but as you say a capacitor on the power rail (ideally two of them, separated by a *very* low value resistor) can do wonders to improve that. The thing to watch out for with linear voltage regulators is that they often require at least one or two volts above the required output and whilst they may improve ripple I'm not convinced it's the way to go as it negates the efficiency of the buck converter. But as you say there are many ways of doing this so thanks for your suggestion, others will benefit too.

Dear Ralph, what if we want to use the arduino to measure the voltage of lets say a battery bank and displays the real time voltage, does it need a special sensor for this purpose? can we manage to do this using the analogue input pins with out the help of any additional parts?

@RalphBacon

7 жыл бұрын

Hi Wael! It's fairly easy to turn an Arduino into a low-end voltage meter, but rather than me explain that you might as well read this article: startingelectronics.org/articles/arduino/measuring-voltage-with-arduino/ which explains it all! Good luck and don't apply more than 5v to any analog (or digital for that matter) pin!

@Waelshamsan

7 жыл бұрын

dear Ralph, that was exactly what I meant by my question, same as the link you give, to use the voltage divider rule to measure the battery banks voltage. Thank you very much Ralph for your reply.

For the buck converter do I need a capacitor like on a 7805 voltage regulator or can I install it just by itself If I do use a 7805 what’s better to use for 12-14 Volts in And 5 volts out the 7805 1 amp or 3 amp thanks for you’re time

@RalphBacon

2 жыл бұрын

For the buck converter it's always a good idea to put some kind of small capacitor on the input and output. For the 7805, whether the 1A or 3A depends on how much current you will be drawing. Remember these things can get really 🥵 HOT so a higher rated item will run (relatively) cooler but you still might need a heatsink. Hence my preference in using a buck (or boost) converter. No heat generated, hardly.

I am getting a current of 3mA from a LM7805. How to increase the same?? Is it linked to input voltage and input current?

@RalphBacon

7 жыл бұрын

Well, when you say you are "getting" just 3mA current, does that mean you have tried to draw more current into a low value resistor, for example, but did not get more? Remember that the INPUT voltage to this 5v device must be 1 to 2 volts more than the output (for the exact value you must refer to the datasheet). Then you will be able to draw up to 500mA (although you MAY need a heatsink as it will get hot). And yes, you won't be able to draw more current that the input current has available. If I have misunderstood please feel free to rephrase your question. I hope this helps?

how is it considered better is what I do not get since a lot of buck converters have a voltage regulator on them I have even seen them on ebay with a 7805 on them

@RalphBacon

7 жыл бұрын

Hello vorkev1, welcome to my channel. Now you say that you have seen buck converters with voltage regulators on them? Me too, like this one here: www.ebay.co.uk/itm/L7805-Buck-Converter-DC-DC-7-15V-9V-12V-to-5V-2A-Step-down-Power-Supply-Module-/172442662702?hash=item282662372e:g:HQUAAOSw6DtYTlL2 But this is NOT a buck converter, is it a standard linear voltage regulator! The whole point (as explained in my video) is that buck converters are EFFICIENT because they do not discard unrequired voltage / current as heat, they simply chop the voltage supply up into a wave that averages out to the required voltage. No heatsinks (usually) required (a big giveaway in that above ebay listing) as it is up to 95% efficient. The ONLY downside of a buck converter is that there can be some residual noise on the output rail so it can't always be used for highly sensitive circuits (RF modulators for example) without further smoothing and regulation. You can't assume that the ebay seller knows what he is selling; the term "buck converter" and "linear voltage regulator" may well appear to be the same thing to the seller, he just knows it converts voltage from one value to another! So it is up to us Arduinites to be aware of what is actually being sold. An excellent point you have raised for others to be aware of so thanks you very much for pointing this out, great to hear from you.

@RalphBacon

7 жыл бұрын

I'm also thinking that if you were to use a buck converter to convert, say, 12 volts down to 5v (very efficiently), then you COULD use a linear voltage regulator to convert the 5v to 3.3v to allow the user to have both voltages available - it might be a cheaper way of giving both voltages as long as the current drawn by the 3.3v was not high thus not negating the efficiency gained by the buck converter in the first place. Yes, I know, it's all a bit confusing. Just a thought...

@jimbarchuk

6 жыл бұрын

The 'buck converter' in the title and description are KEYWORD SPAM!!! Looking at the board if there's no coil and no small IC chip it can't be a switched power supply. Ebay is bloody screaming !RAMPANT! with keyword spam!! (I could show you examples of RC model products that would curl your toenails.) This one -is- a violation of ebay vendor TOS, could be reported and the vendor -should- be shut down till they fix it. But ebay doesn't care any more as long as they get their $cut$. Caveat emptor. That's not to say it's not a handy little PS module! It has 3 power input options, 3 output options including USB, nice little heatsink, a power switch and an LED. Very nice. No mounting holes, but that's what hot glue is for. ;) There will always be need for linear PS. The time saved hooking up these bits on a breadboard is worth the $, just slap it in and it's done. It's very useful for many prototype/breadboard quick-n-dirty 'I need clean isolated 5V right-->here right now' purposes.

Hello I want to install a voltage regulator in my car in the dash for temp and fuel gauges 12 volts in ground and 5 volts out to gauges would a buck converter work or voltage regulator which would be best thanks

@RalphBacon

2 жыл бұрын

Simplest, not necessarily the best, is a simple linear 7805 voltage regulator with a couple of 0.2uF decoupling caps. Watch the heat dissipation; the tab is ground so you can bolt it to the car chassis. For a car, it's the simplest option and no high frequency noise that might upset the gauges.

where did you buy your buck converter and how much did it cost?

@RalphBacon

9 ай бұрын

Probably AliExpress... let me see. Something like this: bit.ly/buckboostexample

if my input is 14v with 2v ripple on the top.. will it work?

@RalphBacon

4 жыл бұрын

Wow! 2V ripple? I wouldn't even call that a power supply! But, yes, I guess it would, although you need a large, electrolytic capacitor in front of _any_ voltage converter to try and reduce that ripple. At least 1,000µF, or several of them!

The car is a 1976 Plymouth can I use a buck converter instead of the lm7805 they both do the same thing right

@RalphBacon

2 жыл бұрын

Yes they do. 12v in, 5v out. Buck converter is more efficient, usually doesn't get hot (unlike a linear voltage converter) but does put high frequency noise on the output. Check what it's like with an oscilloscope if you have one. Or check your car's radio with it temporarily fitted to see if it introduces noise in that.