DC-DC Adjustable Step-down Module 5A 75W (CE07271)

Support Product Questions
21

I’m looking to step down a 12V power supply to power several servos under load (robotic arm). In doing so I’d need a max current drawn of about 8A which this module can’t quite handle. I was wondering if it’s possible to put two of these in parallel to be able to supply 10A in total without any issues?

Thanks!

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22

Hi Domantas
Running 2 supplies in parallels OK for bench work for a short time where the set up is 100% attended. Has to be done with a schottky diode in series with both supplies and the 2 supplies have to be balanced to share the load properly. Schottky diodes are suggested here due to the lower forward voltage drop. If 0.6 or 0.7V can be tolerated then “normal” diodes will do. With bench work power supplies would probably be adjustable so this voltage drop would be immaterial.

This arrangement with 2 supplies and diodes is normally used for redundancy in case of a failure. In this case either supply has to be capable of the full load.

The short answer to your question is not recommended. I wouldn’t do it anyway except for the redundancy requirement where a hot standby is required.
Cheers Bob

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23

Hi,

I’m hoping somebody can help me with adjusting the current limit of this buck converter.
I have it hooked up to a bench power supply at ~5Vdc, I adjust the output voltage of the module to ~3.5Vdc and then I try to adjust the output current limit however no matter how many times I turn the “cc” potentiometer my mutimeter always reads roughly 4A. That value does change by a few mA, but it seems random and not directly linked to any input from me. I have tried this with 3 of these modules and all behave similarly so I don’t think its faulty hardware.

Am I missing something?

24

Hi Cuan
Sounds like something wrong with your measurement set up. Can you post a sketch showing EXACTLY how you are trying to set this.
Cheers Bob
PS. Also what current limit are you trying to achieve and what is the current capability of your bench supply.

25

Hello everyone,

:white_check_mark: I can adjust my voltage to 12V without any problem.
:x: However, I am unable to achieve an output current lower than 2A.

Do you know why?

Here is my configuration:

Input:
Switching power supply MEAN WELL RS-25-12 (12V 2A)

Output:
Amperemeter NEOTEK XL830L set to “10A”

Thank you for your assistance.

26

Hi Julien
I think you might need a little more than 12V in to get 12V out.
Are you aware that the adjustment potentiometers are many turns (probably 20) from end to end. ou may not be turning it far enough and the 2A you are measuring could be the Max A the MeanWell supply can deliver.
Try turning the pot further. When you get to the end of its travel it can keep going with no damage and you will hear a slight “clicking” sound as it ratchets over the end.
Cheers Bob

27

Is the XL4015 DC-DC step Down converter able to convert like 5 or 6v to 12v.
As i have a Powerful 5v battery and i need to power a 12v Module. Would this work

28

Hi Marcus
No. You will need a step UP or step UP/Down converter.
Cheers Bob

29

Oh, But isnt that a step Down converter

30

Hi Marcus.
Yes. But you say you want to go from 5V to 12V. That is UP in my version of English.
cheers Bob

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32

Hi Mark,

What sort of current are we talking here? The power lost in the diode is the voltage drop times the current, so that decides how wasteful it seems.

More importantly, how are you charging a 10S lipo! Most of the chargers I’ve seen only go up to 6S or 8S. Since you are stepping down anyway, could you go 9S or something to keep the step down happy?

Generally if you use a part at it’s absolute maximum voltage for even seconds you can expect damage.

36

Hey Mark,

Thanks for looking into the specs on that Step-Down Converter. I will pass this on to the rest of the team and get that page updated so that it displays the correct voltages.

Thanks again!
Sam

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37

So which trim is for which cunction and CC vs CV - using it to filter car 12v (13.2 - 14.8V) down to 9 v for Vin on Uno and 4 relay shield

38

Hi Linden
CC = Constant current or current limit.
CV = Constant voltage or voltage regulation.

I think you mean Function.
If you go back to the original post and Core product page the controls (CC & CV) are pointed out.
Be aware of the multi turn potentiometers. The subject was discussed in the first few posts.
Cheers Bob

1 Like
39

thanks bob …yes function …
need to click read more to get to 2nd image :<

40

Hi Linden
Go to the very first entry and click on the item description at the top or the “read more” link which will take you to the Core product page.
Cheers Bob

1 Like
41

Hey Linden,

For reference this is the product page link.

DC-DC Adjustable Step-down Module 5A 75W

CC = Constant current or current limit.
CV = Constant voltage or voltage regulation

As Bob mentioned before, to adjust the output limits with the potentiometers keep in mind “the adjustment knobs are 30-turn potentiometers that control the voltage and current limits. This means you may have to turn them up to 30 turns to get from the top of the output limit range (36V) to your target voltage.”

Hope this summary helps!

42

Can this be used to regulate power down from 5Vdc to 3.7Vdc?

1 Like
43

Hi Ravneet,

The headroom voltage of this regulator is 3V, so to get an output of 3.7V you would need 6.7V,

We might be able to help more if you tell us what are you trying to achieve?

44

Thank you for getting back to me!

I’ve got an existing LED system that uses a li-ion 5400mAh 3.7v internal battery, and I’m looking at remove that existing battery and upgrading it to be able to use swappable 6000mAh 3.7v batteries that are individually chargeable. The idea is to extend the operating time for the existing LED system. These swappable batteries would act as power banks essentially.

The existing board that runs the LEDs has +/- pads where the existing 3.7v battery is solders into.

The issue is that most charging boards_
for 3.7v li-ion batteries that I’ve looked at charge on your website offer around 200mA-500mA charging current which would take ages to charge a 6000 mAh battery. There is one board that I’ve found, however, that might be able to charge the battery at 2000 mA, but the only downside with that board it has a 5V boost circuit that outputs 5V 2A via a USB-A connector.

I’m uncertain if existing hardware on the LED’s board can accept 5V power, I can’t identify the parts to be able to look at the datasheet to check this. To play it safe, I’d like to be able to supply it with 3.7V.

I’ve flirted with the idea of using a PD power bank instead with a buck converter.

I’d definitely appreciate some suggestions!

Below are some links to the hardware that I’ve looked at on your website:

https://core-electronics.com.au/lipo-rider-plus-chargerbooster-5v24a-usb-type-c.html?gad_source=1&gclid=Cj0KCQiAqL28BhCrARIsACYJvkcLuEcZMngnPexel2jb7o-mABWvrGHv3aKlmelJV5m1pYQ2Mp-VKl8aAu9JEALw_wcB

https://core-electronics.com.au/polymer-lithium-ion-battery-6000mah.html

https://core-electronics.com.au/lipo-amigo-lipoliion-battery-charger-lipo-amigo-pro.html (just ordered this to try out)

Cheers,
Rav