I am looking for some information buck converter or switching regulator input 80 volts DC adjustable

sam_sam_sam

The picture below is about the testing phase of this project low voltage output transformer tap

I have built a ATX switching power supply auxiliary power supply board the output voltage is about 75 volts with no load if you have a load of 0.500 amps the voltage drops down to about 50 volts and at 50 volts you can load it to about 4 amps ( from a ATX switching power supply ) [ the ATX switching power supply board taps switching transformer outputs }

One note not all ATX switching power supply can be able to be modified like this and the protection circuit still function correctly as normal

I am looking a regular that it’s input voltage need to be at least 80 volts or higher I would like to be able to adjust the voltage down to 12 volts could be a little bit higher if need be

I can find a lot of voltage regulators up to 48 volts but I having a hard time finding what I looking for

Can anyone recommend a switching regulator or a buck converter that has the specifications

Thanks to anyone who can help with this project

If anyone is interested in this project please let me know and I will post more information about this project and how you modify the right ATX switching power supply for this purpose

Mickster

I know why you have the Owon
Bluetooth, right? 👍

sam_sam_sam

You are right and there are times that I do use the Bluetooth function when I want to track the voltage or current over a period of time

evanh

I'm guessing you're after decent amps. You wouldn't be going to such effort otherwise. Got a minimum and preferred 12 V current rating? Why not use the existing 12 Volts?

sam_sam_sam

Because I would like to use this for LED light module testing and other devices that have high voltage

Would this work

DC-DC Buck Converter Step-Down Power Supply Module in 20-70V Out 2.5-58V 30A

https://www.ebay.com/itm/DC-DC-Buck-Converter-Step-Down-Power-Supply-Module-in-20-70V-Out-2-5-58V-30A/124534306896?hash=item1cfed2b850:g:ecsAAOSwCi9gBloK

The 30 amps is over kill because the most I could probably get of this setup is maybe 5 amps maybe this is questionable if I get this much amperage with out tripping the over current circuit and I do not want to disable the protection circuit this is why went with the type of setup

I know that protection circuit works because I tested it several times just to make sure it still works correctly by shorting the auxiliary power supply board leads together

evanh

That's a dead link for me.
LED lighting power is configured as current regulator, not voltage regulator. Sounds like what you're trying to build is a bench-top lab power supply.

sam_sam_sam

@evanh said:
That's a dead link for me.
LED lighting power is configured as current regulator, not voltage regulator. Sounds like what you're trying to build is a bench-top lab power supply.

I fix the link above

Here is what I am trying to do is use the auxiliary power supply board to a buck converter board that has voltage and current that are adjustable “ building a bench power supply ) for the most part yes and be able to power other devices

I problem with one 30 amps current capability is way over kill I only need something that capable of about 6 amps or so

Peter Jakacki

If you are willing to go to such a bulky supply then how about considering an offline switcher device that normally takes rectified high-voltage AC and uses a flyback transformer rather than just an inductor. There's the TOP257 that directly handles 5.44A out and in this case you would just feed it a high DC voltage and these things work well at lower voltages, it's just up to the circuit values used.
I have run mains powered monitors from 48VDC without any modifications.

sam_sam_sam

@"Peter Jakacki" said:
If you are willing to go to such a bulky supply then how about considering an offline switcher device that normally takes rectified high-voltage AC and uses a flyback transformer rather than just an inductor. There's the TOP257 that directly handles 5.44A out and in this case you would just feed it a high DC voltage and these things work well at lower voltages, it's just up to the circuit values used.
I have run mains powered monitors from 48VDC without any modifications.

I am open to this idea the only question I have is what would the components value be for each component and where would I find this information

Thank you for all time and help with this

Peter Jakacki

Read the datasheet carefully and find any appnotes that they might have. Only you know what it is you want and what you don't want. After you have taken in this information, even if it doesn't make complete sense, you at least should be able to formulate a specific question and then understand the specific answer. I would think finding a suitable flyback transformer is the hardest part. Even if you work with the recommended values, you can always experiment by changing values. That's the easy part. The personal research is the part we can't do for you.

Alternatively, try feeding your 70VDC into a suitable 12V laptop style power pack and see if it does what you want.

Tubular

Perhaps the Riden RD6006 will do what you want, it claims to take up to 70 volts in, 6amps out, and is around the $50 mark with wifi a few $ extra

sam_sam_sam

@Tubular said:
Perhaps the Riden RD6006 will do what you want, it claims to take up to 70 volts in, 6amps out, and is around the $50 mark with wifi a few $ extra

I will probably go with this but I would have to put a little bit of a load on the output of the ATX switching power supply board output to drop the no load voltage down some like 65 volts or something close to it and I just put a load across the input of the device that you recommend

By the way thank you for your input to this project

Tubular

The ATX supplies do need minimum loads to perform their specs. The loading on other rails (eg 5v rail) does affect other voltage rails. You may need to experiment with getting a minimul load on the 5v rail