CR1616 Holder for GB Cartridges

Recently, a friend of mine got a GB Operator. I’ve always wanted to dump some of my old cartridges, so I dug up an old copy of Pokemon Yellow and Silver that I’ve had for ages, collecting dust in a box of old games and keepsakes. They haven’t been used in a while for good reason: the internal batteries died years ago, and my last GameBoy Advance made its way into the hands of my younger siblings, so I haven’t had much reason to replace them. I didn’t want to give him a nonfunctional cartridge though, and there’s not much point to playing on a cartridge if your save data won’t stick around.

There was just one issue. There are several revisions of GameBoy cartridges, and they use different sizes of battery, but they all make use of these annoying solder-tabbed batteries. They’re difficult to replace, and since they’ve fallen out of fashion, there are no name brands (that I can find readily available, at least) producing them. You could always solder tabs or wires onto off-the-shelf batteries yourself, but that’s messy and even less friendly to do, not to mention that the heat can be detrimental to the battery life. So instead, why not adapt a battery retainer to the footprint of the solder tabs already on the cartridge?

HDR’s CR2Retainer

Some internet searching led me to a project by GitHub User HDR, the so-called CR2Retainer (I cannot seem to find this project posted under their GitHub so apologies if this link is out-of-date). This was perfect for one of the cartridges I needed to do a battery swap on, which uses a CR2025, so I checked that off my list.

Unfortunately, I couldn’t find anything for the older board with the CR1616 footprint, so I once again fired up KiCad…

Design

The first thing I did was take a few measurements off the board. I measured pads sizes and clearances so I knew the footprint I would have to work with. This drove my component choice for the battery holder, and I settled on the Keystone Electronics 3012TR. It’s unfortunately a bit taller than I wanted, but availability for holders in this size is pretty limited, and I didn’t want to design around an EOL component, so I ran with it knowing I could modify it if necessary.

There are some silkscreen markings that run over the edge of the board, but they’re just clipped in production and unnecessary for anything other than visual alignment, so it’s not a big deal. I had to design a footprint for the 3012TR myself, and the silkscreen doesn’t perfectly align, but I didn’t have one to actually measure and there weren’t dimensions for the angled cuts in the spec sheet.

I placed the order for both the holders and the boards (don’t forget to order them with the flexible PCB option, otherwise they won’t fit!), and a couple weeks later everything arrived.

Eveything fit together snugly, and admittedly the top of the retainer obstructs sliding the cartridge cover smoothly, but with a little persuasion everything came together. All in all, an easy and quick project, and I’m happy with the results! I’ve pushed it up to GitLab, if you want to hack on it, and you can order one yourself right over at OSH Park.