Variable Bench Power Supply for Less than $12! (USB-C PD)

[@BrianLough]

It was my goal to release this on Monday (12th) but I was 5 minutes late, oh well! Let me know what you think of the Video!

[@AitoLaikoSamoMoaCawfy]

its an informative video but is this school project or something cuz this has more details than my pv

[@dogukancil5128]

You "can" set a specific voltage with PD, it is called PPS. A 100-watt PD charger that supports PPS will be able to push any voltage between 3.3 and 21V and can limit the current in 50mA intervals, some even have a higher resolution. Therefore, if you have a pps charger you actually just need a pps trigger board, which is around 6 dollars on Amazon.

[@afurryferret]

I can't find any PPS boards that will actually let you configure current limiting, do you have a link by chance?

[@dogukancil5128]

@@afurryferret PPS protocol is able to limit the current but there would have to be an MCU to communicate that. PPS triggers that I know of wouldn't be able to do that. For battery charging you could just use voltage to limit the current. Alternatively, an easy way would be to use a small arduino to monitor the voltage and current being output and incrementally short the voltage increase or decrease buttons on the PPS trigger to get the desired current.

[@hexefx]

When the current limit kicks in, the supply goes into CC (Constant Current) mode. The output voltage is a result of the ohm's law: U = I*R, where I is the max set current and R is the load resistance. Hence the output voltage is not going down to 0V. PSU is regulating the voltage to keep the current at constant value.

[@BrianLough]

Thanks for the explanation!

[@andymouse]

What a neat little supply for the money ! ...nice work Brian...cheers.

[@BrianLough]

Thanks 👍

[@MartynDavies]

Thanks Brian. I will definitely build one of these, as more and more USB-PD power supplies are now turning up. Re: your power switch: I built a power supply a couple of years back and have often wished that I put the main switch on the front panel, since the power supply now sits underneath a monitor and I can't easily reach the back.

[@IanSlothieRolfe]

These modules are designed to be capable of being used to power industrial equipment like CNC machines, so defaulting to "ON" makes sense in that context, you'd want to power up the whole device with one switch if you have separate modules powering the different axis, for instance. They give you the option to select because they are also designed with charging batteries in mind (NiCd and NiMh and possibly lead acid). These goals make them ideal for a cheap bench power supply as you have found. I recently bought one of these and ran it through its paces, and it seems pretty solid, more so than the more expensive module I bought 18 months ago, and the user interface is easy to use. The use of a PD module is an interesting idea, although at the moment the only power banks I have will only supply 5 or 9v so that might be a future upgrade - at the moment I am using an old 45w laptop supply whose irreplaceable connector broke forcing me to replace the whole supply. The case I designed has a sloping top like yours - great minds think alike!

[@PMcDFPV]

Good stuff ! I just ordered the parts :) month or so and they should be here, but i have time to refine the case design till then :) thanks sir !

[@BrianLough]

Hey Paul, a few people have worked on new cases so maybe there will be one that works better for you, I'll update the description later with them

[@bitluni]

*pause* I don't have a scope.

[@daviddavid-up1jc]

Somebody send this man an oscilloscope please

[@vince086]

Built something very similar recently, super useful for my projects and takes up barely any desk space. Also added a XT60 connector so I power it from a LIPO when traveling. Used the RIDEN DPS5005, it only does step down so when using type-c I'm limited to the max of PD, wish I had known about the module you used. Although the interface on mine is way nicer.

[@BrianLough]

Thats a good idea! I don't have any high capacity LIPO so my power bank will do for the portability I need. I can only imagine it's nicer ok! I just wanted to make the cheapest thing I could and see what it was like, but as mentioned in the video, I was surprised that it was actually decent! I think you'd get used to the interface on this, other than the slowness of changing values.

[@Leif_YT]

I'm in the same boat. I build two based on the DPS5005 and so far i never ran into a situation where i needed a voltage boost so i'm very happy with the DPS5005 and its user interface. For the input i've used an USB-C Module like Brian did and a barrel socket for laptop power supplies.

[@TheTinkerDad]

Nice project Brian! If I remember correctly, a year or so ago Seon, you, me and some other guys talked about USB-C via Twitter and I remember that back then I didn't see all the goodness USB-C brings. Oh boy I was wrong! :) I wonder what else USB-C will be useful for in the future.

[@BrianLough]

It is pretty amazing! I did get a 100W supply recently and a Load that is able to draw that, and in fairness it did output basically that, was pretty surprised (and scared!)

[@jerril42]

Thanks Brian. This is great. I've been thinking how I could make a portable electronics kit. A couple of batteries the PowerBlough with a TS80 and this PSU covers a lot of the basic needs.

[@BrianLough]

Cool idea! yeah it would cover most things ok!

[@allthegearnoidea6752]

Bugger you beat me to building this by two years! ❤ great video

[@pault6533]

Nice job. For better heat dissipation through natural convection the top could be vented above the heat sink, because hot air rises. To avoid dust these slot openings could be louvered. The colder air will flow in nicely from the existing slots in the base.

[@wandersonsilva-fx1cs]

I'm intending to build this font, and I really liked your project. Well explained. Thanks

[@justicator]

Hi Brian! I built one similar to this using a WZ3605E, but fried it when i attached it to a battery, (not sure what happened?) I want to rebuilt it and saw that this board you used is basically the same spec, but cheaper. Hoping it works well.

[@jerzeek]

I'm willing to work on the case :), Just ordered all the parts!

[@BrianLough]

I look forward to it! Please share here or on my discord if you get around to making it!

[@circuitdotlt]

how well does it limit current? If I set it to 30V 5A and connect to a 12V battery, what happens?

[@1982lifegoeson]

In this video found what I was looking for, I bought an earlier voltage controller motor but not working well as expected now I believe that this would go good on my project :)

[@darknessblades]

For the 3D printed case you can make it as big or as small as you want. [within limits] using smaller switches is also highly reccomended

[@edwardfletcher7790]

This is an excellent solution for hobbyists, I love the size compared to my stupid big desktop PC power supply ! Thanks very much for sharing ! You're doing some really great stuff on this channel, Subscribed ! PS: I found the ZK-4KX $3 less than that !

[@padraigwastaken]

really impressive! Would I be right in thinking I'd still need something like this for a device that uses a 12v 3a power supply even if the power bank can do 12v 3a or would it be okay to be feeding in the maximum current?

[@ericchang7706]

If someone wants to bundle all this stuff together, including the buck/boost module, I'd be interested in buying it. If you do, maybe add a separate DC input via barrel plug (for laptop power supply) as we all have plenty of those laying around and this module can isn't picky about input voltage.

[@tomb2623]

With this ZK-4KX you can use any old modem, router, laptop DC power supply, no need for fancy usb-c stuff :)

[@ezwizzard]

Nice video. If I buck the source power down, can a Kobalt 40-volt battery serve as a PD compatible source?

[@scellyyt]

I made a similar one using the latter module you mentioned and a 135w computer power supply brick. I've limited it to 60w because the connector I bought for the power brick plug is limited for that, but with the inefficiencies of the module I'd guess it's consuming over 75w.

[@skysharksingh]

Excellent video information and superb presentation. Thanks

[@BrianLough]

Glad you liked it

[@deankq4adj125]

I know that it needs improvements, but this was a great design and concept!

[@gelukken5246]

I have a simular module (WZ5005L), but it does a very poor job on over-current protection. It actually raises the voltage in steps to the set voltage, and only then after about 200ms it starts checking the current. If there is an over-current, it then drops the voltage to match the maximum set current. This means it will feed the circuit with at least 200ms of both an over-voltage and over-current, most likely destroying the circuit. What it should do is raising the voltage in (very) small steps at a reasonably high frequency, measuring the current in the process. If the either the current or the voltage is over the set value, it should stop right there and everything is fine. It can repeat that process if you lower the voltage or current. So be careful with this module, as it could destroy your circuit!

[@TBL_stevennelson]

I impulsively ordered all the stuff.

[@BrianLough]

Such is life when watching electronics youtubers :D

[@RobertShrimpton]

I plan to impulsively order all the stuff very soon!

[@joshuamichael4101]

Ehm can you reverse the role of that unit, so if you have a DC power supply and then you want to connect it to usb type c device for charging that device. Does it fits the 2-in-1 solution or it cannot and you have to make another product for that purpose. Please answer my questions, I really wanna know what would happen/can happen, thank you :)

[@Avipami]

would you recommend the lp2721 to be used for a 20v 3a led light ? are there many pd chips that dont require programming to use a specific pd profile ? I saw that the cypress chip has this setup through a choice of resistors

[@BrianLough]

If you are careful about the chargers you plug it into it would work fine. (Cause it can only negotiate 20v, it doesn't know it can /can't do 3A) Yeah the cypress should work too

[@Avipami]

@@BrianLough thanks for the input. Maybe ill have to go about another route for this.

[@mumbaiverve2307]

I have got one of these units. The CC does not seem to be working as expected.Suppose I set the voltage to 5V and a max current of 100mA, if I short the output or put a sufficient load ,the output current stays at 60mA.Also the CC LED does not light up.Any suggestions ??

[@BrianLough]

That's the version with two USBs right? The version I have only has one micro USB, we are dubbling the other one "cyd double USB". I've ordered one but it hasn't arrived yet. I was discussing it with someone on my discord and they confirmed it doesn't work with a USB C-C cable, indicating the designer forgot the resistors on the cc lines. It does work on a A-C cable, so you can use it with an adaptor

[@mumbaiverve2307]

@@BrianLough Thanks for the super quick reply ! I am actually testing the ZK-4kX Buck Boost module. I am supplying with a 12V SLA battery just to check the operations and settings. Everything else works as expected,except the issue I mentioned. The current is getting limited, just that it is not hitting/holding the set CC value of 100mA.

[@NicksStuff]

I wonder if the efficiency would be better with a PPS power source

[@curiousworld6644]

Thanks for uploading this video

[@davidgunther8428]

Great video! A lot of videos just show the construction of the project, not how to use it too.

[@james10739]

Ya I believe qc3.0 is supposed to be able to do .1V steps but I haven't seen a power supply like what you built that could use it

[@user.A9]

ZK-4KX - is there a way to lock the controls so people can’t change them?

[@james10739]

I think I'd use thicker wires for the output but I think I saw 2.5A at some point so 22awg probably isn't far off

[@___Eldritch]

So I know it's been a minute since you made this video, but assuming a throw 1000amps into this buck boost converter am I going to destroy it or will it still step it down to 4 amps on the output 🙄

[@JaveedChip_Smith]

Ehat happen i f we Connect a 5v battery in input and make it rechargeable? It will be ok?

[@dariomateo7801]

Do you sell the complete system already set up?

[@ChimeraX0401]

Does anybody know where I can get the schematic diagram and data sheet for ZK-4KX, I really need it for a presentation, so please can you link it, thanks....

[@nidusa1]

would you be able to make an EPR PD3.1 bench power supply for at least 5amps/28V or 140W ? Apple sells a PD3.1 charger that is 140W.

[@BrianLough]

The PSU module I use is limited to 50W, 140W would require something significantly better, I'm not sure you'd be able to get anything like that for cheap

[@PedroLarroy]

Is this earth referenced or floating?

[@blackrat9712]

Hey, could u pls show how to use the esp32 gamepad library cause i want to make my own android arcade style gamepad but i only have a analog joystick and buttons

[@hulkgqnissanpatrol6121]

Wow, I just found 5 of them for $4.67 USD including postage and tax 😂🤣 Thanks for the run-down 👍

[@24pavlo]

10:00 "As for ripple, don't worry, according to the listing it has a low ripple ... I don't have a scope" I almost pissed myself here.

[@PlasmaJunkie]

I had a good chuckle at that one too.

[@adilislm-th2jy]

ZK-4KX DC DC Buck Boost Converter I can run a 12 volt 2 amp fan with it ?

[@johanrynjah8241]

Yes, you can easily run a fan of that power rating through this module. You can also use this module to speed-up or slow-down the fan.

[@nutty4u2c2002]

Can the ZK-4KX be reset to factory settings.

[@giorgiob.6437]

Great video!

[@ghadysmith]

how are you supposed to charge an 18650 with this

[@joliettt]

Great job.

[@EasyOne]

nice

[@MrTolin23]

👍👍👍

[@j5892000]

If you boost voltage your power bank needs to supply much more current..just to boost.. then take into account the device being powered amps needs. You'll likely Not have much current to work with lol

[@BrianLough]

That is covered by setting the power limit.

[@Serghei1958]

Video!

[@jgbelmont]

Dont go too high on the amps. Those modules are junky and overrated.

[@SebastianScholle]

worst interface ever ;-)