Setting Up the Buck Step-down Power Converter Module

[@PaulFillmoreIII]

Boy was this note helpful! " Several users of this module have complained that the output voltage does not change when the small brass adjustment screw is turned. Try turning the screw counter-clockwise MANY times. It may require 10 or more counter-clockwise turns before the output voltage begins to change."

[@peterfenwick2540]

Thank you Jeff, please don't ever take this video down as I am sure to be looking for it again in about a year or two.

[@YesThatDan]

Was considering this converter for a project, and went to KZbin to see if there was a video. Yours was the first hit. Very helpful. Thanks a million! 73, ----Dan

[@RealAstronomyBoy]

I'm pleased that you found my video helpful, Dan. 73, Jeff

[@AdamAve93]

Thank you so much for clarifying all of that for me. I was having trouble figuring out how to drop a 7.5v power supply to the 5v connection needed. Very helpful!

[@kevin6685]

Thanks, I want to make a swamp cooler bucket and the power supply for the blower fan is way much greater than the intake fans that i want to use

[@Rick_Cavallaro]

You're my hero. Well done! Thanks! I found that you can also select the current output display mode, hold the rt button for 2 secs, and calibrate that display just as you did with the voltage display.

[@RealAstronomyBoy]

@@Rick_Cavallaro Thank you!

[@Rick_Cavallaro]

@@RealAstronomyBoy I also found the answer to one last question I was looking for... The display modes go through voltage, current, and power (in watts). For some reason, I was too dense to figure out what 0.1P meant.

[@RealAstronomyBoy]

@@Rick_Cavallaro You have provided some very good information. Once I learned how to use this module as a voltmeter and voltage regulator, I did not delve into the current and power display modes. So I'm sure you know much more about those modes than I do.

[@Rick_Cavallaro]

@@RealAstronomyBoy Thanks. If I know more about them, I've only known it for about 30 mins. But I've gotten to where I write everything down in a file so I don't have to do the research again. Wait'll you become a geezer. You'll see. :)

[@NoHandleNameScrewTube]

Wonderful I have this module and had ordered it months back and had no instructions. This is awesome because I didn’t figure the most important part calibration. Thanks

[@madhusudanm6529]

Whats the price??

[@93556108]

You're a good instructor and I have subscribed to your channel. Thank you.

[@macknack2650]

In Germany we say - This Video has Hand and Feet - thumbs up !!! Only this video shows the correct calibration to get minor deviations. Edit : By the way - there is also a output-calibration mode.

[@techydog7854]

Bought one Ebay without even knowing how to use it. This video changed that.

[@RealAstronomyBoy]

Glad I could help.

[@GeorgeWilloughbyZ]

Thank you so much for posting this. I was struggling and about to send the module back !!! All working now :-)

[@RealAstronomyBoy]

Glad I could help, George. Without instructions, this module is difficult to figure out. - Jeff

[@englishrupe01]

Amazing change in price over a couple of years......i just bought 10 of these for 22 cents a piece! Crazy good value! Thanks for the video!

[@downundergarage6968]

More updates please. Best video on it so far.. Cheers

[@rcthomas7090]

Thx for makin this vid. Like so many, i received my modules with no instruction and did not know how to calibrate. You have been a big help! Once i calibrated, my module would not switch display between in and out reading, but disconnecting input for a few minutes and re attaching corrected that. Thx again Jeff

[@TheObaby18]

Great, simple instructions. Thank you.

[@neatpleats11]

Thank you so much. I bought a 1.5 watt solar panel to keep my battery charged and the solar panel will change voltage depending on how much sunlight. I wanted to lock the voltage to match the 12 volt battery and this should keep the output at the 12 volt output I want.

[@Peppermint1]

The reason for the Voltage not changing is the adjustment screw has a brass contacts which oxidize over time and no longer make electric contact. Unplug the unit, then grab the screwdriver with two fingers and start rotating the screwdriver back and fort quickly for a few seconds. This friction should clean up the brass contacts quickly. You may have to repeat this every once in a while

[@FynbosGarden]

Big thumbs up. Crystal clear. Thanks

[@RealAstronomyBoy]

You are most welcome. After I learned how this module operates, I wanted to share the information. - Jeff

[@preciouss5254]

Thanks that's what I was looking for to convert 12v down to 5v, thanks for the video

[@RealAstronomyBoy]

I'm pleased I could help. -- Jeff

[@VechnyiStrannik45]

I didn't know it had a calibration mode - thanks!

[@RealAstronomyBoy]

Glad I could help! - Jeff

[@mmtruckingllc657]

Excellent video very helpful and informative!

[@RealAstronomyBoy]

Thank you!

[@jeoffer]

Great information on how to use this module.

[@roybarrett8296]

Brilliant video, really well explained, for a newbie like me this was just what I needed. So I went to EBay and ordered one Thankyou

[@javierramirez691]

Thank you, very helpfull and informative video!!

[@RealAstronomyBoy]

I am glad to help.

[@compubyte2010]

Excellent stuff..a bit slow for me. But hey, small price to pay for great information like this!!

[@Peppermint1]

I have a question. If the input voltage will vary slightly (such as feeding from a battery that is discharging), will the lower output voltage stay constant ?

[@RealAstronomyBoy]

I have not tested this module with a varying input voltage. I invite anyone with a variable DC power supply to perform some tests and post the results in these comments. Thanks - Jeff

[@AlienWacker]

I hope you're still watching the comments... 🤓 I bought 3 of these from China, and I came here to see if I was doing something wrong - when I adjust the screw at the top, nothing happens.... Thank you for letting me know what the buttons do, and yes I was looking at the output voltage... I suppose I could just use them as volt meters, they do seem quite accurate for that, but I would rather have them as regulators... 😵

[@RealAstronomyBoy]

Try turning the small adjustment screw counter-clockwise MANY times. It may require 10 or more counter-clockwise turns before the output voltage begins to change. I have five of these modules, and all of them have required at least 10 counter-clockwise turns. - Jeff

[@paps69shed]

@@RealAstronomyBoy thanks Jeff. I was just about to get rid when I read this. Lots and lots of turns then eventually the voltage started to fall :) works great on my tiny water pump!

[@RealAstronomyBoy]

@@paps69shed Many users of this module have given up on it before realizing that many turns of the adjustment screw are required before the output voltage begins to change. I am pleased to hear that your module is now working as expected. - Jeff

[@paps69shed]

@@RealAstronomyBoy thank you

[@mjfirthau]

Very well described, thank you sir, mine came without any instructions. Now I know.

[@RealAstronomyBoy]

You are very welcome - Jeff

[@javier_dogue]

Justo lo que estaba buscando, gracias por el aporte!

[@kenthompson420]

Jeff: I'm trying to use this to maintain the charge on a LiFepo battery from a standard AC wall wart. Idea is to maintain the battery for extended periods at 12.9 volts. Maximizes battery life. Battery has no load on it, standby for emergency radio use. But it doesn't seem to hold at the set point. Any thoughts on what I may be doing wrong? Wish I had watched your video before I started with this project. Written instructions are not clear, at least to me. Thanks for your clear video instructions. Ken

[@RealAstronomyBoy]

Ken - I'm glad the video was helpful. I know nothing about battery charging LiFepo batteries, so my comments may not be especially useful. You do not state the input voltage to the converter module. The input voltage must be about 2V higher than the desired output voltage. Thus, if you want 12.9VDC out of the converter, you'll need at least 14.9VDC on the input. Also, you'll get a more stable output voltage if the input voltage is regulated. Many wall wart power supplies are not regulated. - Jeff

[@flavioalmendrales9090]

Gracias! Excelente explicación para poder ajustar este modulo.

[@anicetomaldonado]

How about a video on the lm2596 something something. It has three pentoimeter screws along the positive side. Everyone's guess, small battery charger? I would love to hear your explanation. I understood everything you said as you demonstrated what was happening. You got my attention.

[@royallan3717]

Hi Jeff, I am looking at 3 phase dc motors used in a/c. Spinning fast I get 160 v dc. Input will be variable from wind speed. Would this be suitable ? I have a cheap voltage selector for constant output. Than you for this video

[@RealAstronomyBoy]

Hello Roy. It is not clear to me exactly what you hope to do with this module. Please understand that the maximum input voltage for the module is 40 VDC. The highest voltage I have ever applied to the module is 15 VDC. -- Jeff

[@philc.9280]

do you know if there is a converter that will take a 12 volts DC source to run my laptop at 19.5 volts DC ? I'm trying not to use a 12 volt DC to 110 volt AC inverter. Thanks.

[@cri8tor]

Hi. I purchased a little step up/down power converter (LM2577S) with a 3-digit display, much like the one you use in this video. Please consider a short review and how-to tutorial for this unit. Cheers

[@RealAstronomyBoy]

I'll need more information than that! Where did you purchase your converter? Do you have a photo of it? How about a link to the seller? - Jeff

[@cri8tor]

Listing title on eBay, "Digital Display DC-DC Step Up Step Down Boost Board Buck Converter Power Module." Link: www.ebay.com/itm/Digital-Display-DC-DC-Step-Up-Step-Down-Boost-Board-Buck-Converter-Power-Module/253284321017?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

[@RealAstronomyBoy]

Well, if I ever feel like experimenting, perhaps I will purchase one of these boards. However, I do not have a need for one, so I probably won't be buying one. - Jeff

[@Davidsmith218]

I had one tried to step down 24v to 12vdc to run a 12vdc 1 amp led strip and it got hot and stop adjusting volts so now put in 24vdc it steps down to 22vdc and 14vdc to 12vdc ? Becarful of the equipment your attaching it may burn up your equipment or something more valuable have fuses

[@RealAstronomyBoy]

Thanks for that report, David. It's the first I have heard of that sort of problem. It makes me wonder about how much quality control to expect from a $2.00 circuit board. - Jeff

[@CCCcCCC00210]

Sir, if I input a small Dc generator and this input is turned by hand and the input is not consistent(like 12~ 28V), can I use this device to output 5V? Can't it be used if the input is not constant?

[@RealAstronomyBoy]

That is a good question! Unfortunately, I do not know the answer. If anyone has experimented with a variable input voltage, please tell us your results. Thanks! - Jeff

[@claudioabado6246]

Can you solder an external potentiometer? For convenience? I need to be able to vary the output voltage with means other than a screwdriver to drive LEDs for visual color matching experiments with students. Thanks for your patience and help.

[@RealAstronomyBoy]

I have not attempted to connect an external potentiometer, but it should be possible. On the modules I have purchased, the blue multi-turn pot has a value of 10K = 10,000 ohms. You could set the on-board pot to its highest value, solder wires of a convenient length to its three terminals on the bottom of the circuit board, then connect the wires to an external pot. If you do this, your external pot will be a parallel with the on-board pot, so it may take some experimenting to find an appropriate value for the external pot. Alternatively, you could de-solder and remove the on-board pot and connect an external 10K pot in its place. - Jeff

[@russellmoore1312]

Like this sending my customers who I sell to, to this link

[@jonathanrodriguez8219]

Nice explanation!

[@krishnakumarphy1]

Solar panel open-circuit Voltage: 40V Battery 12 V (AGM Controller : PWM controller max input voltage 28V I need to step down from 40V to 25V and connect to solar charge controller to charge the battery. Will I lose energy in this converter in step down mode? Or the module will convert in to Amps from Voltage while step down? which buck converter would be the suitable one? Thanks, Krishnakumar

[@RealAstronomyBoy]

I'm sorry, but I know nothing about the requirements for your application. - Jeff

[@safefix]

Do you know anything about this unit having a timer? The last couple of years I've used these units powered from a car batteries to power small sets of Christmas LEDs (current draw is way below the 2A max. and operating at 4.5V). Because the car battery has enough energy to run them continuously for at least the 3 weeks needed, I leave them on 24-hours. However, they seem to switch on and off at around 8-hour intervals, though I don't know the exact timing - I'm not going to sit there watching them and wait! Is there any specification sheet that mentions this and is it at all programmable? I'm pretty sure this is a timer issue and not a duty-cycle/power shutdown because, as I say, the output load is very low, about 35mA. Thanks.

[@RealAstronomyBoy]

Hi John -- The LM2596 chip around which this module is designed does not contain a timer function. I have read numerous descriptions of the module but have never seen any mention of a timer. With that being said, I have never operated this module for more than 2-3 hours at a time. The module does have a thermal shutdown feature, but if you are really drawing only 35mA, it seems unlikely that the module is overheating. In other words, I am stumped! -- Jeff

[@viaoutdoors]

Thank you! Great explanation.

[@jonogunn]

Mine was working just fine when I first tried it but suddenly stopped outputting voltage. I tried to adjust the output via the screw but it doesn’t change. I have turned it counter clock wise 100 times now and still doesn’t do anything

[@RealAstronomyBoy]

My guess is that your board has failed. I initially purchased 5 of them, and in the past 6 years, one of my boards failed.

[@jamescowpersmith4318]

Video very well done!

[@TheTechLab]

nice video , vary informative , i wont you as my teacher

[@samds]

Hello. Can we add 2 devices at the same time on the out side? (2 12V fans in my case) Cheers.

[@RealAstronomyBoy]

As long as the two devices together draw less than 2A, this should work. - Jeff

[@compubyte2010]

And I'm assuming voltage can't exceed max, when combined??

[@nlreversespeech]

Thank you! This calibration method also works for the cc cv xl4015 model with two potmeters and 4digit lcd. Quite surprised I found this video because keyword 'calibration' is only found in the comment section of this video. That's why I mention it also works for the 5A cc cv model with usb socket, for those looking to calibrate it.

[@RealAstronomyBoy]

Thanks for mentioning 'calibration.' I've updated the tags for this video. - Jeff

[@crankygrandpatech3894]

Great info thanks so much! well done!

[@markwallis7199]

Thanks for the video, the input calibration worked great. However, nothing that I do changes the output voltage from the input voltage, there isn't even a drop between the two. I can change the display to read whatever I want but it doesn't effect the output, neither does turning the trimmer pot. It would be nice to see your voltmeter on the output.

[@RealAstronomyBoy]

Mark - You may have to turn the small brass adjustment screw 10 or more turns counter-clockwise before the output voltage begins to change. If the output voltage does not change, you may have a defective module. Although it's not on the video, I did have my Fluke voltmeter connected to the output during testing. In fact, I used my voltmeter to calibrate to module so that the output voltage matched the displayed voltage. - Jeff

[@markwallis7199]

@@RealAstronomyBoy Thanks Jeff, I got there in the end as I hadn't expected it to require this process and of course it came with no instructions. I did get it very confused at one stage whereby it wouldn't come down below a previous set point but perseverance paid off. Now I'm suitably impressed.

[@RealAstronomyBoy]

@@markwallis7199 Glad you got it working, Mark.

[@changxiyuan9241]

Hi Thanks for the great video, may I ask is this XL4015?

[@RealAstronomyBoy]

I am pleased that you like my video. The module in the video uses a LM2596S regulator. - Jeff

[@syedzaharudin06]

If we reduce the volt...is the amp also reduce?? Example... 18 volt 8am battery? Reduce to 12volt??

[@RealAstronomyBoy]

This module can provide a maximum of 2 amps. It can never provide more than 2 amps no matter the specification of input power source. - Jeff

[@victororo462]

Thanks for the upload!! I tried mine and the voltage output would not drop! I turned it many many times and still nothing. Finally..after turning it like crazy, the voltage started dropping. Very cool! I thought that I was losing my mind for a while.

[@RealAstronomyBoy]

I'm glad you persevered and got working, Victor. Well done! -- Jeff

[@wernhereksteen4360]

Do you need to power it by a power supply or can you connect it directly to a battery as the power supply?

[@RealAstronomyBoy]

I have not tested this module using a battery, but it should work -- for a while. My concern is what will happen as the battery discharges and its output voltage decreases. As the battery voltage decreases, the output voltage of the module may decrease as well. This applies to any battery, but a high-capacity automobile battery (for example) will maintain its voltage under load longer than a smaller low-capacity battery.

[@salsepulveda494]

Example: The input to this LM2596 is 14.4V at 0.70A - Does this unit maintain a constant 2.0A even though the input current is 0.70A? I understand that you can't get more voltage than what is put into it, but what about AMPS - the same situation?

[@RealAstronomyBoy]

This board is not a constant current device, if that is what you are asking. More to the point is that you'll never get more POWER out than you put in. Power is measured in Watts. 14.4V at 0.70A is about 10W. Theoretically, if the board is 100% efficient, you could operate with an output of, say, 5V and draw 2A, which is also 10W. However, the board is NOT 100% efficient, so you might be able to get 3V at 2A or 5V at 1A, or something of that nature. Power OUT can not be greater than Power IN. - Jeff

[@justinerigali3236]

Great video! Thank you.

[@DupczacyBawol]

If you set the output to 5V and the input voltage would not be reliable and change in time from 6V to 19V does the device keep always the 5V on the output?

[@josecarlosmarquesjuniormar244]

Readme .txt Keeo at least 1,8V above your reference voltage. Yes it keep a constant voltage on output.

[@pandaencolere3160]

hello, I would like to power a camera back between 3.7Volts and5volt (380Mah max). when I go to adjust the step down in + -3.7Volts how many amperes I would have in output?

[@RealAstronomyBoy]

According to the specifications for this module, you will have 2 Amps available. - Jeff

[@pandaencolere3160]

thank you, it will save me from killing my FPV cam! it is written 3.7V 380 Mah max. I can hope to find a step down or I would have max 380Max, or I have to stop looking? I spent my day on ebay :( and hello everyone from France@@RealAstronomyBoy

[@RealAstronomyBoy]

Your cam will draw only as much current as it requires. The module can provide UP TO 2 Amps. That does not mean your cam will draw 2 Amps. - Jeff

[@pandaencolere3160]

Thank you very much, you answer my question ... The amperes I did not understand much the concept, I understood now when you say, it can provide up to 2 amperes. I am bad in electricity, sorry@@RealAstronomyBoy

[@douglazamar8889]

is there such module which would take say 5v and do output say 3v to 32v? my similar module tskes say 15v it can lower to like 1v and up to 15 of input but it wont give anything above it, is it defective?

[@RealAstronomyBoy]

If you are using the device shown in my video above, it will NOT produce an output voltage that is greater than the input voltage. - Jeff

[@TW39]

Can I use a 3.7v lipo batterie on the input and adjust the output to 6v

[@RealAstronomyBoy]

No. There are two things to consider. 1) This a step-DOWN converter. The output voltage will never be greater than the input voltage. In fact, the input voltage must be at least 2V greater than your desired output voltage. If you want 6V output, the input voltage must be at least 8V. So you will need at least three 3.7V lipos in series to get 6V from this converter. 2) The maximum output current this converter can provide is 2A. Therefore, you must be certain that the load connected to the output of the converter draws less that 2A. In addition, you must also be certain that the maximum continuous discharge current of your lipos is at least equal to the current required by your load.

[@milvolts1]

Bought one and the digital voltage readout stopped working. Would you have an idea as to what it could be. I know they're cheap. But I hate waiting a month for another. Thanks for your great video

[@RealAstronomyBoy]

I'm sorry, Mario. I do not know what cause the problem. These modules are not expensive, so I suggest you purchase more than one. - Jeff

[@nilsz7354]

I've got one but i used it a few times with 12v and now it doesnt turn on and the transistor near the input gets hot. Is there anything i've done to destroy it?

[@RealAstronomyBoy]

We Are Anonymous You might have drawn too much current. These boards are specified for a maximum of 2A; if you attempt to draw more than that, components on the board may overheat and eventually be damaged. On the other hand, you might have simply purchased a defective board. - Jeff

[@Fredericvda1]

Hi Jeff, I need to transfer power from a fully loaded (car) battery which is 13,7V to max 12V to supply power to my 12 volt led lamps. When I use 13,7 V directly on my 12V led lamps, they last only a few hours. Some sources say, when difference between input and output is to small (1V or less) , it will not work. What will eventuelly happen as the battery discharges. As you have the module, can you confirm me if this is true? Thanks in advance!

[@RealAstronomyBoy]

Hello Frederic. I have a power supply with a fixed output of 13.9 VDC. Using this power supply, The highest output voltage I can achieve from the module is 13.0 VDC. This tells us that the input voltage to the module must be at least 0.9 V higher than the desired output voltage (at least in this voltage range). This suggests that you'll maintain 12 V out of the module until your battery discharges below 12.9 V. Of course, your LEDs will continue to work at less than 12 V. The LEDs will simply get dimmer until the voltage declines so far that they no longer turn on. LEDs draw so little current that your car battery should last a long time before its voltage drops too low.

[@papapika4920]

i want to step up my power supply to 13.8v and i need about 20 amp,can i use this?

[@RealAstronomyBoy]

NO. The module described in my video is a step-DOWN power converter. It is used to reduce the input voltage to a lower output voltage. Also, the maximum output current this module can provide is 2 Amps. - Jeff

[@ajosin]

Is the output always on or can it be switched on/off by pushing the buttons. Thanks for the video 🙏

[@RealAstronomyBoy]

The output is always on. You could add an external switch on the output if you wish. - Jeff

[@ajosin]

@@RealAstronomyBoy ordered. Thanks!

[@randyrowe1182]

Do you know what project box would fit this unit. Thanks. Great video.

[@RealAstronomyBoy]

This board measures 2-3/16 x 1-3/8 x 1/2 inches or 56 x 35 x 13 mm. There are no doubt hundreds of project boxes that will fit this board. - Jeff

[@Kelly_Soares-l1w]

Does it amplify the voltage? Does it convert a lower voltage to a higher output?

[@RealAstronomyBoy]

No. This module is a STEP-DOWN converter. It can only convert the input voltage to a lower voltage. - Jeff

[@Kelly_Soares-l1w]

@@RealAstronomyBoy Thank you!!

[@jakevlogs1258]

Can i have a question sir? This dc to dc step up converter can set in to 13 volts and can, charge the 12.6 18650 battery pack ?

[@dejanzdravkovic9010]

Ja,i allready tried with li ion and lipo...it works perfekt!

[@jakevlogs1258]

@@dejanzdravkovic9010 ok thank you

[@LOTPOR0402]

If u connect a 12v battery to it and set the output to say 6v ,then connect a 24v battery will the output still be 6v ,or do u have to reset Reason for asking is i want to use it with a 12v solar panel to charge a 6v battery {solar voltage changes with the sun } Thanks

[@RealAstronomyBoy]

Mark -- I have verified that the output voltage remains constant for small changes in input voltage. For example, when changing input voltage from 9V to 14V, the output voltage does not change. I do not have a DC voltage source greater than 14V, so I can not test larger range of input voltages. -- Jeff

[@erwin2tarmac305]

can i use this to power a laptop (19 volts) using six 18650 batteries in series as input

[@RealAstronomyBoy]

Possibly. This module can supply a maximum of 2 Amps of current. If your laptop requires less than 2 Amps, it might work. - Jeff

[@erwin2tarmac305]

@@RealAstronomyBoy I think i need to buy 2 and connect them in parallel and use a car battery instead, will it give me 19 volts 4 amps?

[@RealAstronomyBoy]

@@erwin2tarmac305 NO. This module is a step-DOWN voltage converter, not a step-UP voltage converter. The output voltage can never be greater than the input voltage. A fully-charged car battery produces about 12.5 V, perhaps a bit more. So, when connected to a car battery, the maximum output voltage of this module can never be more than 12.5 V. Another point: I don't know if these modules can be operated in parallel. I have never done it, nor have I heard of it being done. - Jeff

[@erwin2tarmac305]

@@RealAstronomyBoy Oh my bad, i mistook it for a 6009 boost converter

[@fatimazahraejaaouan2529]

Thanks for the video, it's very well explained, i have just a question about if i could use it to get high voltage in the output than the voltage in the input (step UP converter)

[@RealAstronomyBoy]

Hi Fatima - NO. This module is a step-DOWN voltage converter only. The output voltage can never be greater than the input voltage. In fact, the maximum output voltage is approximately 2 V below the input voltage. - Jeff

[@fatimazahraejaaouan2529]

@@RealAstronomyBoy Ah i understand it. Thank you

[@drchan5893]

very good sir i use already to power cordless drill because the battery no more work

[@n0spam911]

Im planning to run with 18650, what happens if input V drops below recommended 4.3 V?

[@ApocGuy]

i think they run from 1.5 or 1.8V onward. but would suggest to check data sheet before connecting anything.

[@compubyte2010]

We will All die !! .. maybe .. so don't let it go below 4.3 lol

[@moleszzsolesz6389]

Hy. mine just down to translate, no high. What problem? input voltage may be down, not up

[@RealAstronomyBoy]

With this device, the output voltage can not be greater than the input voltage. -- Jeff

[@deanlane]

HI, Thanks for the detailed video. This is exactly what I was looking for. Question: I want to convert my 12v down to 5v BUT i still want the 12v power supply to run a LCD screen. Can you split the 12v wires and run one set to the step down and the other to the screen OR can you run the wire directly from the input clamps. Hope this makes sense as im only new to this so go easy haha. Thanks

[@RealAstronomyBoy]

Hi Dean -- Your idea will work fine provided your 12V power supply can handle the load. For example, if your 12V supply is a tiny "wall wart" type, it might not provide enough current to operate both things at once. Assuming it's a larger 12V supply, it should work fine. - Jeff

[@deanlane]

Thanks Jeff for the reply. I assume a wll wart power supply means those small square wall plug and not the ones with a big brick attached? I do have a smaller supply which is 12v 3a. Since I would like to run a couple of 5v devices off this then Ill may grab a larger supply. I need to run a raspberry pi, google chrome cast and a small suet of usb speakers on the 5v line. Im hoping to split all that on a usb hub. Thats the plan anyways. Sounds like I have more research to do. Thanks again Jeff

[@federox86]

i ve a battery in 36v 20ah, i ve a 12v dc 600w 52amp motor (for boat). the question is: if i use a step down power can i use this battery for have much ah? in theory 36x20 720ah. is correct? thx for response.

[@RealAstronomyBoy]

I do not know the answer to your question. Maybe some else will post an answer. -- Jeff

[@imtoouncreative8263]

The motor will take as much ah as possible, but as stated in the video the driver can only output a max of 2ah

[@miteshdhanani]

How can we connect it with 3w 6v solar panel

[@adjgamer]

Just ordered a pack of 5 of these for servos for my drone because I don't have a good 5v out for them

[@mixme8655]

Thank you very helpful as beginner

[@jago5300]

See going in on the input at 120 v + amps?/ or is it DC ? + Amps?

[@RealAstronomyBoy]

This is a DC-to-DC voltage converter. Maximum input voltage is 40 VDC. - Jeff

[@dlerhajiagha]

Why mine tiny screw not respond? I do the same procedure.

[@RealAstronomyBoy]

Turn the tiny screw many turns anti-clockwise (counterclockwise). It may take 10 or more turns before the output voltage begins to change - Jeff

[@jago5300]

So the input is DC not AC, it's dc-to-dc is that correct

[@RealAstronomyBoy]

That is correct. This is a DC-to-DC voltage converter. - Jeff

[@jordani-colts9671]

Thanks for this video! Great work! I bought one of these... but mine is the 5A version. Would it still do the same job with say 3A of input voltage? (Just curious... Im into electro-chem. and plating... so I'm not really much of an electrical engineer lol) PS: Any idea where the heat sink is supposed to go lol!

[@RealAstronomyBoy]

Please note: I have no experience with a 5A version of this module. With that said, the phrase "3A of input voltage" is rather puzzling. Amps is a measure of current, not voltage. Perhaps what you are asking is whether your module can power a device that draws 5A of current if the power supply for the module can provide only 3A of current. The answer is: probably not. As for the heat sink, I've never used one with my modules. However, I have seen small aluminum heat sinks that are meant to be attached to the LM2596 on the circuit board. The LM2596 is the black chip-like device with 5 contact legs protruding from it. - Jeff

[@skrya1248]

Is it trustworthy enough to power a Raspberry Pi4? I recently bought another step down (bit pricier) but 7,4V supply voltage wasn't enough. I kinda scared powering expensive stuff with these cheap converters. Anyone has any experience?

[@RealAstronomyBoy]

I suggest purchasing a dedicated power supply for your Pi4. Here is one power supply that will work: www.adafruit.com/product/4298 - Jeff

[@thulasiramanp1033]

Hi Sir can I get the purchase link Sir

[@aldiband9171]

bang, what is the function of voltage regulation ???

[@RealAstronomyBoy]

In the context of this discussion, voltage regulation is the ability of a power supply to provide a constant output voltage over a range of load conditions. For the circuit board shown in my video, the output voltage will remain constant for a load of up to 2 Amps. - Jeff

[@aldiband9171]

if the settings are in the middle according to the video, I want to make a battery, bro ..

[@CriticoolHit]

Thank you!

[@joesam8113]

Jeff can use this unit for changing my car battery?

[@RealAstronomyBoy]

Sorry Joe, but I don't have any idea if you can charge a car battery with this module. Perhaps someone else will have an answer for you. - Jeff

[@m.saad0501]

Thanks man

[@GeraltOfRivia69]

If i press the button for a very long time.i can change from -5 to +5, what is this -5,+5??is it amps?

[@RealAstronomyBoy]

I do not see this behavior from the boards I am using. It is not amps, because the board can source a maximum of 2A. If you try to draw more than 2A, the board will probably overheat and may be damaged. - Jeff

[@DelooPabet]

Your unit only has one button? If so this is a universal voltage caliberation across both input and output to display + or - 0.* volts

[@DelooPabet]

If your reading 4.9 volts but supplying 5 and you can calibrate to +1 to get to it to display 5, but your output display will also add the 0.1 to its display and may be off

[@DelooPabet]

Also i believe that unit is a voltage step UP converter not the step down unit in the video

[@GeraltOfRivia69]

Deloo Pabet it is a step down converter,with only one button.i think you are telling the right thing.i think it is a calibration thing

[@chrismagallanes8858]

Can i use this to shock a motherboard to see what mosfet is bad?

[@RealAstronomyBoy]

Hi Chris -- I have no idea what it means to "shock a motherboard." So I cannot tell you if this module can be used for that purpose.

[@chrismagallanes8858]

@@RealAstronomyBoy so i have a motherboard that is fried but i need to inject voltage to see what mosfet is damaged

[@RealAstronomyBoy]

@@chrismagallanes8858 As long as your application does not draw more than 2A, my guess is that it will work. But since I have never done this, I take no responsibility for any problems that may arise. - Jeff

[@hdofficialstudio6824]

Thankk youu👍👍👍👍👍

[@zoranpocrnja2646]

If you press the button for 3 seconds gives you other hacks on voltages;!

[@eviloctober]

Can you use this as a dimmer

[@RealAstronomyBoy]

What is it that you wish to dim? - Jeff

[@ChapuDelValle]

What is the thing that has 101? Whats its purposes

[@RealAstronomyBoy]

That component is a 100uH (micro-Henry) inductor. Looking at the schematic diagram for this and similar modules, I have noticed that power converters based on the LM2596 regulator chip utilize an inductor. However, I do not know what purpose it serves in the circuit. Perhaps someone more knowledgeable than me can provide us with that information.

[@fouzanjaved5441]

thank you, sir.

[@alexabadi7458]

Mine never worked, can't change the output voltage.

[@alexabadi7458]

IF THE "OUT "VOLTAGE DOES NOT WORKS (DO NOT CHANGE) THEN DO THIS: TURN THE DIAL COUNTER-CLOCKWISE AT LAST 10 TIMES AND IT WILL START WORKING AGAIN !

[@glenemo2079]

@@alexabadi7458 Fabulous and critical advice Alex - on mine was completely unable to change the o/p voltage no matter how I adjusted the trim pot. So as Alex says I disconnected the unit and turned the trim pot "counterclockwise" (holding board so that the input of the brd was on my left) more than 10 turns then powered up the unit and the o/p voltage displayed at about 1.2V, then by turning the pot I was able to finally adjust the o/p voltage to the level I needed... That's what you need to do to get this module working properly...

[@milvolts1]

Can I charge 18650 batteries with this. Thanks

[@RealAstronomyBoy]

I know nothing about using this device to charge batteries. - Jeff

[@milvolts1]

Jeff DeTray I thank you for the reply. But what do you use this for?

[@RealAstronomyBoy]

mario sellet I use these to (1) monitor and display the output voltage of a power supply and (2) provide 5 VDC for low-voltage circuits. These boards are so inexpensive that it makes sense to dedicate each one to a specific purpose. - Jeff

[@DelooPabet]

For example you could add these units to a side box on the shown 13v power supply each with its own posts and have several different voltages from the power one power supply. 13v 5v and 3v if you had 2 units

[@nx5515]

What if the output is not accurate? How to adjust that?

[@RealAstronomyBoy]

I've tested five of these boards. In all five cases, after the input voltage has been calibrated, I have found that the displayed output voltage is accurate and does not require calibration. Jeff

[@tubebechard]

Jeff - I have a couple of these boards, but adjusting the potentiometer doesn't have any effect on the output reading. I've tried with a 17v IN and a 5V IN and in both cases the OUT matches the IN. Turning the Pot does nothing. Thoughts?

[@RealAstronomyBoy]

Try turning the voltage adjustment screw 10 turns (or more) counter-clockwise. It can require many turns before the output voltage begins to change. - Jeff

[@michaeljohnn2598]

It's been a while since this video My question is can I use battery with 3.7V as INPUT to get 12V OUTPUT any idea I will appreciate everyone who helps me Thank you

[@RealAstronomyBoy]

Hi Michael -- The answer is NO. The output voltage will always be less than the input voltage. That's why this module is called a "step-down power converter" as stated in the title of the video. - Jeff

[@RealAstronomyBoy]

@@michaeljohnn2598 Please look closely at the banggood page. It says: >> The input voltage must be 1.5V higher than the output voltage or 1.5V above.

[@michaeljohnn2598]

@@RealAstronomyBoy now I understand the funny things is i bought 30 of those LM2596 seem I will throw them away Because I can not use them i want to use battery with 3.7V for led with 12V once again Thank you Jeff i Sub :-)