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I'm trying to design a PCB to use some large capacitors. I recently discovered that there is a much wider and cheaper range available as long as the capacitors are snap in style.

How exactly do the footprints work for these? The datasheet just shows two holes as usual, is there anything else needed? Do the leads fold over as the capacitor is snapped into the PCB? Is any additional clearance needed around the cap to account for the folded leads? Are they easy to replace once the electrolyte dries up? I want to make my device easily serviceable. Standard capacitors can easily be desoldered, but I wonder if snap ins are as well.

To install, you just put the leads through the holes and push down until they fold over?

Do snap ins have any disadvantages?

Edit: I realize snap in capacitors still have to be soldered, just wondering about how they physically "snap in", and if the larger leads prove more difficult to desolder, and if you can "unsnap" them to replace them if necessary.

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    \$\begingroup\$ it looks like the the "snap-in" function is just for mechanical anchoring without having to fold the pins over ... you still have to solder the pins \$\endgroup\$
    – jsotola
    Dec 24 '19 at 4:18
  • \$\begingroup\$ I think these parts are soldered in. the snap action (a temporary positive action like on a 3.5mm jack) only retains the capacitor during wave soldering. this is not a solderless mounting methid like pres-fit terminals provide \$\endgroup\$
    – Jasen
    Dec 24 '19 at 4:46
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As others already commented, snap-in is to temporarily fixate the capacitor on the PCB.
TDK states about snap-in:

The snap-in aluminum electrolytic capacitors feature two pin or three pin snap- in terminals making them perfect for easy mounting on the PCB of the application. (source)

And

Snap-in solder pins to hold component in place on PC-board (source)

$$$$

I think this drawing from Würth Elektronik shows how a snap-in capacitor just fits and therefore "snaps" in and how the capilary solder joint should look like.
Note the leads are not (further) bent.

enter image description here

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  • \$\begingroup\$ Thank you so much for this, this is exactly what I needed to know! :) \$\endgroup\$
    – cat pants
    Dec 24 '19 at 20:35
  • \$\begingroup\$ Do you know what the "fixing material" is? Is that glue? \$\endgroup\$
    – cat pants
    Dec 24 '19 at 20:36

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