I had the similar requirement for Flow meter application before...
I had done only paper design work....

My requirement was -

Input-
85VAC-265VAC 50Hz
18VDC-36VDC

Output- 15W

Means i wanted to implement a single SMPS design which works with above range.

I wanted to give free hand to customer that whether he power up the flowmeter either by 230VAC or 24VDC at a time.


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Mod note:
Please don't hijack other member's thread, now you have your own.

This thread was split from --
30VDC to 480VAC Input range to 24 V 10 Amp powersupply.

 

Us knowing what voltage the flow meter worked at would have been helpful.

Also for factory made off the shelf devices they typically have a specific input voltage requirement and related connector which for the most part rules out the need for a single input wideband power supply to power them.
laptops, for example, are such a device. They are either being powered by standard AC line voltage which is supplied by a dedicated power supply with a specific shape of input plug connector for said AC power sources that does not and will not fit any standard direct DC power source, like those found in automotive environments, where such power outlets are the DC power port type. Or the reverse where they use a power converter unit with a specific range of DC input power.

There is no DC source plug that will fit into a standard AC power outlet either so the related power converter unit only needs to work with the ranges of voltages that would be commonly found in such DC-powered environments.

The closest hybrid you can get is the dual power type 5-volt USB chargers units and even they use two separate types of plugs and internal voltage conversion systems in them. One two prong AC one with its dedicated SMPS conversion circuit and one automotive power port type with it's dedicated DC - DC buck converter circuit.

Simply put, in this application, the two ranges of power inputs needing to be supplied through a common singular input connection point which are to be converted to a specific output are a non-issue.