The Goal: Add NiMH recharging via USB-C to a Game Boy Color, allowing use standard AAs, and allowing rechargeable AAs to be charged via USB-C.
Background/Overview: I see a lot of USB-C mods where people add LiPo batteries to the Game Boy Color with TP4056 boards to achieve USB-C recharging. This is cool, but it has a few downsides I really don’t like. First, it requires a lot of altering of the battery compartment, including both cutting out the plastic and removing the battery contact terminals, to fit a LiPo battery. These changes are permanent, and you will no longer be able to use standard batteries with that unit. Second, LiPo batteries drain pretty quickly when not in use. So if you’re a casual user, you will likely need to recharge your GBC prior to playing. This seems pretty inconvenient. Finally, LiPo batteries don’t last forever, but the mod requires you to integrate the battery with the unit. If you ever need to change the battery, you’ll need to solder again. For these reasons, this mod was never for me. That said, as much as I like to use standard AAs to power my consoles, having a USB-C recharging option sounds really cool. So I set out to have the best of both worlds – the ability to use standard batteries in my GBC, but also charge over USB-C. This tutorial walks through how I achieved this.
Warning: Don’t do this if you’re not comfortable soldering, or don’t want to potentially mess up your favorite childhood toy! I’m not an engineer, electrician, etc., I’m just a dude who did this through trial and error. If you want to try, do this at your own risk!
- Game Boy Color
- NIMHCRTA charging board
- USB Type C connector
- NiMH rechargeable batteries
- Soldering iron
- Insulated wire
- Hot glue gun
- Kapton tape
- Flush cutters
- Recommended: Dremel, de-soldering wick
- Prep the charging board: solder 4 wires to the NiMHCRTA board. The B+/B- will eventually solder to the Battery solder points on the PCB, and the others will go to the USB connector. I use different color wires for +/- to make my life easier, but this isn’t required. I recommend making the wires long since they’ll need to be routed around once they’re in the system. You can always shorten them if necessary!
I recommend insulating the board with some kapton tape.
- Prep the inside of the shell (Note, you’ll see I did some additional cutting to the frame and D-Pad. I’m only noting what is required for the battery mod here, but while I had the system open I also did an IPS mod and added an amplifier. I won’t point these out in the tutorial to avoid confusion).
First, use flush cutters to remove the post next to the D-pad
After, smooth it out and it should look like this:
- Place the board and route the wires. The LED on the board will sit next to the “B” button. I used clear buttons on this build so it’s clear when it’s charging. You can see I’m also doing an IPS mod, so my only option here was to have the LEDs face inside. If you’re using a stock screen, you can flip the board around and the shell will glow while charging. I positioned B+/- at the top and GND/VIN at the bottom. You can see how I routed the wires below.
- De-solder the the DC port. This is critical since it’s in the optimal place for the USB connector. You also need to bridge the two points shown below once you remove the board, otherwise the system won’t work!
- Cut the USB hole. Take your time here so it looks as good as possible. I drilled two holes and then slowly filed until I had a good fit.
- Place the PCB and solder charging board to the battery solder points, and GND/VIN to the USB connector. I didn’t take the best picture here, but you want to solder B+ and B- to the appropriate solder points on the board (where the terminals are soldered). As you can see in my second picture, I have more wires since I also added an amplifier. You can ignore those.
- Place and glue the USB connector. I recommend first insulating the USB connector with some kapton tape. Take your time with the glue, and make sure it’s dry before moving to the final step. Avoid using too much glue, or you might run into issues closing everything up.
- Close everything up! As always, be careful to make sure your wires don’t sit on top of any screw points! You can test that everything works by dropping in your NiMH rechargeable batteries and plugging in a USB-C cable. If you see a red glow, it’s working and the batteries are charging. Once they finish charging, the light will turn off. Your Game Boy Color can now use any standard AA batteries, and can charge and rechargeable NiMH batteries!