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I've been trying to convert a high voltage input to a lower voltage (5V at around 3A) with no luck using these Modules

and all of the LM2596HV iteretions of modules out there and all seem to make some audioable noises with their inductors even with lower loads.

Now I'm looking for either a solution + explanation for it and or a better module product with quite a small form factor that can withstand these specs:

60V+ Input voltage

5-12V 3A output

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  • \$\begingroup\$ high mu ceramic ferrite and high Dk capacitors are crystalline materials and are known to be piezoelectric. To avoid this requires research and communication with the supplier and an understanding of the current crest factors and ferrite material and shape. \$\endgroup\$ – Sunnyskyguy EE75 Sep 7 '18 at 19:32
  • \$\begingroup\$ Hello Michael, welcome to EE.SE. Well what would you expect for $1.78? Try going to www.mouser.com, looking under power, then DC-DC converters. Pick the input ranges wanted, then 5v output. The resulting list will be quality parts that will all work well. eBay "modules" tend to be very cheaply made, with design optimized for price and nothing else. \$\endgroup\$ – rdtsc Sep 7 '18 at 20:56
  • \$\begingroup\$ digikey.com/products/en/power-supplies-board-mount/… \$\endgroup\$ – Matt Young Sep 8 '18 at 4:23
  • \$\begingroup\$ But still I can't believe such a regulator would cost so much in a product... I would maybe understand such a thing would cost just twice as much from the ebay listing. \$\endgroup\$ – Michael Sep 12 '18 at 9:46
  • \$\begingroup\$ see this rohm.com/products/power-management/switching-regulators/… \$\endgroup\$ – user19579 Oct 26 '18 at 11:32
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The inductors are likely poor choices for the switching frequencies, or specific voltage and currents used for the regulator, and the circuit layout may not be ideal to reduce electrical noise. As mentioned in the comments, this is a basic side effect of bottom dollar designs and manufacturing. You get what you pay for.

There is no practical solution for your existing modules. You could attempt some reverse engineering, replace the inductor with a quality one of the right inductance for the circuit, and voltages/currents involved, but that's not easy without years of power regulator design experience. Quality ones, will cost much more. Except sticking it in a fairly sound deafening enclosure.

Side note: The regulator itself could be the issue. The LM2596HV costs 3 USD a piece in 1000 unit purchases directly from Analog Devices (Who owns Linear who designed the original). It's a clone at best and a fake at worst. It could be out of spec and cause switching noise through the inductor even if the inductor is ideal.

That said, product recommendations are off topic here, so we can't guide you to a specific one. As mentioned in the comments, look for dc-dc converters on your average electronic supplier site, Digi-Key, Arrow, Farnell, etc.

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  • \$\begingroup\$ TI now owns National, not Linear :) \$\endgroup\$ – Peter Smith Sep 8 '18 at 10:45

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