I need to throw a 12V 1.5A power supply into a box that’s roughly 5"x5"x3" and still have room for a board I’ve been asked to make. The board can be as small as .5"x3" depending on how tight I’ve got to make those components. Luckily, I’ve got very small chip options.
I’ve looked for transformers that will fit in a case that size, and while I’ve seen dozens of switching power supplies that are that small, I’ve not been able to find a transformer rated at my needed current levels that’s small enough (and preferably pcb mounted) to handle the job. I’ve used EI-30 form factor transformers for lower power jobs and have been happy, but at 2VA, they’re obviously unsuitable.
Anyone have any favorite options?
Must the supply be mounted inside the box? If this box is going to be AC wall outlet powered anyway not something like this:
Unfortunately, the transformer etc must all be inside the same (small) box as the MCU itself. Shielding and other concerns are going to have to be dealt with.
see here www.jameco.com/ mybe one fit for you
Thanks - I had looked at those earlier. I'm looking for (essentially) as small a version of THIS as possible:
It just strikes me that with the rather large number of (smaller than this) wall warts that are in the 12v/1.5A range, that there might be smaller (than this) units out there bare like this.
How about this one?
Could you also accept 2 smaller units?
Make sure to get all your grounds connected so every one is at the same ground reference level.
Crossroads, are you suggesting that i buy these and take them apart? I’ve considered doing just that, but it’s not a good long-term solution for me.
This is closest yet:
It's still larger than what would be found in the smallest DC wall warts. My issue if getting this wouldn't be having space for my board, but would be having space for my board + one accessory connector + (the big one) shielding between the psu and mcu.
The 1st one I suggested just use as is, connect the 2 pins to whatever AC receptacle you are using.
If you have a 5"x5" box, that raises up 3" this can lay in the bottom and still give tons of room in your box - 3"x3"x5".
Or cut an opening, let the square part and the power prongs stick out, plug an extension cord on the end of it. Couple of small holes and secure it to the face with cable ties.
Wish I had a way to post a quick drawing.
No, I see where you're going. The issue is that this is a commercial product, not one of my arduino projects. Gotta look classy
I'm using an IEC C8 for the power cord, so there is a bit of space taken up there (I've accounted for this space before giving dimensions above)
In case anyone isn’t aware of the type of jack I’m talking about:
Well, if you can’t find a little bare board to put in, then trim the AC plugs and solder wires from the plug to the trimmed legs.
Have you considered what effect 15 Watts is going to have in an enclosure that small?
This one might meet your requirements, though it'll take a little finagle'in with PC Pins.
CONV AC/DC 20W 12V OUT 1.65A
2.06" L x 1.07" W x 0.93" H (52.4mm x 27.2mm x 23.5mm)