NEEED INPUT: 24-100V DC DC CONVERTER AND OUTPUT: 5V

[markobetti]

GUYS HELP,

Cant find this : NEEED INPUT: 24-100V DC DC CONVERTER AND OUTPUT: 5V( total power 1w or 2-5w)
Does it exist or needs to be manually made .. I would prefer of the shelf solution

Thanks in advance

 

[amberwolf]

Check out your celphone charger.

It may well operate down to 24VDC (though some won't start working till 35-50VDC)

 

[markobetti]

yeah , but this will be used for battery input voltage ad needs to be smaller than that...and also ready to buy xx pcs - for on board computer display ...

 

[amberwolf]

Ah. If you didn't need to just buy a bunch of readymade ones, it could be made a lot smaller by taking the PCB out of the casing, as most of the ones I've opened up are not even 2 square inches of PCB in there, maybe a centimeter tall at most for component height (capacitors, transformer).

As for input, all the celphone chargers I've got here except an old heavy Nokia one are SMPS and will work from a DC or AC input supply. If you bypass the bridge rectifier then they'll work on about 1.4V lower DC input than before.

But I don't know if you can buy standard lots of the PCB part, without the rest of it assembled around it--if you could, that'd probably be a usable solution for you. Perhaps even have them potted with just input and output leads coming out.

 

[bigmoose]

Marko, I have been starting to do the background engineering on such a device. None of the National Simple Switchers go to 100 V with margin. I have had to go to a "roll your own" type design approach, that includes designing and winding custom magnetics. I am months away from stable prototypes however...

That said, your input range of 24 to 100 Volts is the most challenging. The converter is most stressed at high output load and low input voltage. To raise the 24 V low end would be most beneficial. Also 1 W and 2-5W is a significant range when designing the magnetics. Again the upper end needs to "really" be needed as it drives the core size required.

Give another scrub on the input voltage and output current, and if you can share a bit on the footprint you are looking for. For input voltages below 75 Volts I would use one of the National parts, around $4/ea in low quantities.

Edit: Checked and you can push towards your limit with the LM5116 in a buck arrangement. Works out to about 23 discreet parts with a BOM cost of about $5.90 in 1000/quantities. The LM5116 has a max voltage of 100 V, so no margin for spikes.

 

[markobetti]

Bigmoose thanks, maybe its just a right thing , i have to check. Also , amber thanks for advice, but its just too much complication for what we re doing.
That kind of dc converter is needed for display system we are testing

 

[regmeister]

deleted

 

[rolf_w]

maybe Synqor has what you need? e.g. this has not exactly the input voltage range and too much power but is available very low cost on ebay. Wider ranges and lower power might be available as well? r