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I am trying to replicate this charging connector on my board :

enter image description here

it's basically a magnetic base that charge via contact of the pins.

The only way I can think that this is done is via pogo pins:

enter image description here

Once the board is screwed inside the case, the pogo pins are contracted and contact is made.

Does anyone have experience with this kind of design? Am I right about the pogo pins and if yes, is it something reliable for a product used in rough conditions? (considering the pins only make contact with the board and are not soldered.)

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    \$\begingroup\$ The charger side seems to have those pins, while the device side has solid contacts, no moving parts. And there are plenty of solderable pogo like pins. \$\endgroup\$
    – Passerby
    Mar 28, 2017 at 1:41

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The design you show is done with pogos. Springs could also be used but pogos are cheap and typically have better industrial design appearance. These are widely used in medical and consumer industries.

The contact can be quite good if both sides are gold and kept clean by the end user. Datasheets tend to be ~50-100 mOhm and in practice I've seen closer to ~10-30 mOhm nominal connection. This does depend on your contact and spring force tho, so your mileage might vary. Various designs also exist that may conduct through the spring or through the shell of the pogo. Custom designs are possible to meet impedance requirements or current requirements.

Pogos are robust in axial loading as long as you stay within their working range. Pogos do terribly under lateral loads, usually worse than springs. A side force on them tends to fracture the solder quite easily or break the pogo. There are through-hole pogos but they are still not really designed for lateral forces. Usually the mechanical design requires that they are somehow protected (such as being placed in a pocket which ensures no side loading). The pogo side of the mate typically goes on the charger. The other side is typically just a puck and can be super robust as it can have no moving parts. It's better to put this side on the product (assuming you'd rather replace a charging cable instead of the whole product if misuse breaks the pogos). Pogos with a roller bearing at the top do exists and perform better under lateral loads to the tip but are more expensive and more limited in mechanical design freedom.

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If the pogo pins get grit in the shaft they will get stuck and not make contact. If the pogo pins get bent (by keys in your pocket etc) then they will not slide in and out normally anymore. You need to protect the hole where the pogo pins are visible on the outside of the case from dust ingress and physical damage.

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