We’re working on a project that has a battery backup, but we don’t have any more coin cell holders on hand. No problem, we remember seeing a double pin header used for this. But when we… ...

It’s powered via a Micro USB connector, and has a small regulator on board to step down the 5 V supply to the requisite 3 V expected from a typical coin cell.

The two coin cells were in their own somewhat “elegant” removable holder in a pocket away from the PC board, and connected to the board by a pair of modest-gauge wires so they are somewhat independent ...

BTW, according to my vernier calipers, the 4.5 V AR18 coin cell measures 18.8 mm thick, 23.3 mm in diameter, and has a crimped seam around the middle with a 25.1 mm diameter, in case you are curious ...

Planned in the popular 2032 size (3.2mm thick, 20mm dia), it has been developed alongside a more traditional rechargeable 2032 cell for wearables such as watches and smart patches, and was promoted at ...