I am looking for advice on the most efficient way to provide galvanic isolation between input and output DC voltages of the same value, i.e. if 12V was input, the output would also be 12V but with galvanic isolation.

A transformer with a fixed output would not be possible as the the input can range from ~5-24V so the output would need to mirror this value.

This would need to be achieved using smd components.

 

How much power would this isolated (and changing with input DC voltage) DC voltage need to supply to a load?
https://forum.allaboutcircuits.com/...-galvanic-isolation-feature.64680/post-443946

 

the most efficient way to provide galvanic isolation between input and output DC voltages of the same value

Likely an isolated switching supply, depending upon the output power required.

 

SN6505
Designed to produce isolated supplies to run galvanically isolated data transceivers

 

If you are asking about signals, the opto-isolator is a straightforward way to pass signals back and forth across an isolation barrier. The reason I am adding this suggestion is that your term "input and output DC voltages of the same value is not well defined since you say you are already providing galvanic isolation between the input and output.

Here is yet another PRIME example of the inadequacy of verbal descriptions of circuits. If you want an accurate answer, then please provide a properly drafted schematic diagram. If you cannot or will not do that then I suppose you can kick rocks until a mind reader joins the forum.

ETA: Where did you get the quaint notion that transformers have fixed outputs. The output voltage is a function of the input voltage and the turns ratio. How does that lead you to conclude that transformers have a fixed output voltage. You might need to review AC Circuits 101.

 

5-24V is quite a range. do you need to transfer power or just signals/information? how many channels?

 

This would just be the transfer of power and not signals. Current needed to supply the load would be <0.5A.

@Papabravo - An opto-isolator isn't an option as it's the transfer of power and not signals. The point I was making in relation to the fixed transformer output was if a 1:1 turns ratio was used (as this is what I would need). A lot of standard transformer driver options have an input of 3.3-5V and wouldn't provide the output I am looking. I am looking for transformer driver options or something similar that could have an input range from 5-24V using a 1:1 ratio.
P.s. I'll let you know if the mind reader ever appears on here whenever you get down from your high horse.


After a bit more research I found a SMPS transformer that meets the spec. Thanks everyone for their input and for the suggestion @crutschow.

 

From the title:

between input and output DC voltages

I am looking for transformer driver options or something similar that could have an input range from 5-24V using a 1:1 ratio.

Transformers do not work with DC. Get this out of your head.

An opto-isolator isn't an option as it's the transfer of power and not signals.

The opto-isolator would be used as a reference for an adjustable power supply. That is likely the simplest way to do this. You would need a device optimized for linear operation.

 

After a bit more research I found a SMPS transformer that meets the spec. Thanks everyone for their input and for the suggestion @crutschow.
[/QUOTE]
Next you’ll be asking for a circuit to drive it.

 

We shouldn't be too hard on people who use the term "transformer" in what people in NA consider "incorrect".

I have seen everything from DC-DC converters to LED drivers coming straight from the factory with the word TRANSFORMER plastered on the label in large block fonts.

 

We shouldn't be too hard on people who use the term "transformer" in what people in NA consider "incorrect".

I have seen everything from DC-DC converters to LED drivers coming straight from the factory with the word TRANSFORMER plastered on the label in large block fonts.

It likely has a switching transformer inside the DC converter. So that's correct, technically.

 

No, the labels don't say "contains a transformer" it labels the entire unit as a "transformer".

 

No, the labels don't say "contains a transformer" it labels the entire unit as a "transformer".

I'm afraid that it has become a common misuse of the word, where it has a more general "transform" meaning, thus referring to any device that transforms a voltage from one value to another, whether AC or DC.
For example, some AC wall-worts with a DC output use that term.

 

It's all about convention.

In NA we reserve the term transformer to describe a single type of component.

IE: magnetically coupled inductors.

Not every country or manufacturer follows this convention.

 

No, the labels don't say "contains a transformer" it labels the entire unit as a "transformer".

That's just your interpretation.

It's only looks like a DC-DC converter. There's more than meets the eye.

 

By your logic the label could just as easily say "DIODE".

 

By your logic the label could just as easily say "DIODE".

There is logic in badly translated/worded labels? I've seen some head-scratchers over the years.

 

For extra points for pedantry, don't forget that the device you find in a flyback converter is not a transformer (because it doesn't store energy) it is an inductor with multiple windings.

If the TS has in fact bought a switched-mode Dc-DC converter, it is unlikely to meet his requirements of having the output voltage equal to the input voltage.

 

For extra points for pedantry, don't forget that the device you find in a flyback converter is not a transformer (because it doesn't store energy) it is an inductor with multiple windings.

If the TS has in fact bought a switched-mode Dc-DC converter, it is unlikely to meet his requirements of having the output voltage equal to the input voltage.

It might even have a Mag-amp for regulation.