Warning: OBSOLETE VERSION - If you don't plan to use the original DMG front PCB with the original screen I suggest to produce the DMG V2. Link here

VIS_Game_Boy_DMG

This project was born with the aim of saving corroded boards of Gameboy DMGs or SNES Super Gameboy adapters. For this reason, I developed replacement PCBs by using modern electronic components. Several exisisting DMG mods are included:

• Lipo power board that also provides the negative voltage required for the original LCD (this voltage can be turned off through a switch if an IPS screen is used). Thanks to a brand new 2.5A DC jack, a lipo battery can be safely charged at 0.5 or 1 A. In addition, it is possible to play while charging by using only the current coming from the DC jack.
• Audio board with all the audio circuits on it in which 1w speaker or the original speaker is directly connected (Audio is not sent to the front PCB, and, for this reason, any power absorbing on the front PCB does not affect audio). Audio amplifier can be disabled to save battery life or to use only the pro-sound jack.
• Integrated bivert chip.
• I also developed a replica of the OSD IPS (v4 or v5) board with button LEDs and tactile buttons.
• Housing shell doesn't require any cut apart from those required by the IPS LCD mod.

Videos related to this project can be found on my YouTube Channel.

Warning:

I have updated Gerber file of the mainboard to v1.1 on PCBway, in which an important fix has been done. If you have produced v1.0 of the mainboard, send me an email and I will tell you the fix that must be done.

Disclaimer

This is a DIY project for electronic enthusiasts. For this reason, I am not responsible for any damage incurred while attempting this project or after completion of the project. You alone accept all risk since you are 100% liable for damage to yourself or your property.

Security information for Lipo Battery

The battery is physically distant form the tp4056 linear charger. In addition, the following features are implemented:

• Overcharge and overdischarge protections achieved through the widely used and widespread combo FS8205A - DW01A.
• Load sharing: you can safely play while charging the battery since the battery is disconnected from the load while charging (I use the same circuit of SYF Game Gear since its creator allowed me to use it).

Credits

Gekkio for the DMG schematics

Switches/selectors

Before assembling the console, the following switches or selectors must be properly set:

• The switch on the mainboard to turn ON/OFF the bivert chip.
• The selector on the mainboard to use normal video or biverted video.
• The switch on the powerboard to turn ON/OFF the negative voltage required by the original LCD.
• The selector on the powerboard to set 0.5 A or 1 A charger.
• The switch on the IPS board to turn ON/OFF the button LEDs.

Finally, from the battery compartment, it is possible to ENABLE/DISABLE the audio amplifier without opening the console.

Required Donor parts

In this project, the strictly required donor parts are only

• the CPU (that can be sourced from a donor DMG mainboard or a SNES super Gameboy adapter).
• the link-port (that can be sourced from a donor DMG mainboard or from a 4-player adapter DMG-07).

Other optional components to desolder from a donor console are:

• RAM chips (can be sourced from a donor DMG mainboard or a SNES super Gameboy adapter) or the Alliance AS6C6264-55SIN RAM chips can be purchased.
• Card slot connector, volume wheel, and quartz oscillator can be sourced from a donor DMG mainboard or can be simply purchased on Aliexpress.
• Power switch can be sourced from a donor DMG mainboard, or a brand new switch can be purchased at any electronic components shop (see BOM file).

Required Parts to purchase or reuse

• All the electronic components reported in the BOM file.
• Housing DMG shell case (optional if you already have one).
• IPS LCD kit (optional if you want to use the original front PCB). If you want to use the VIS front PCB, you have to buy the v4 or v5 OSD version (see the FAQs here for more details). You can find (in the files of this project) the 3D model of the LCD bracket (IPS v5). You can simply 3D print it (I suggest transparent), and then you can prepare it with sandpaper and paint it with the color you need. This model of the bracket fully masks the entire LCD (it is useful if you use a transparent shell).
• 3.7V 125054 Lipo battery (optional if you want to use only the DC jack) (see the FAQs here for more details).
• 5V 2A USB-C charger with a DC jack adapter (it is shown at the end of the instructions).
• Kitsch-Bent full silicone buttons (optional).
• 1 Watt speaker (optional if you want to use the original DMG speaker). You can find (in the files of this project) the 3D model of the holder that you can use to take it in place without glue it to the housing shell.
• wires and ph2.0 housing connectors reported in the last sections of the BOM file (optional since you can solder directly wires on the boards).
• flat connectors 21 pin pitch 1.25mm if you don't find them you can simply buy the 22 pin version (clearly also a 22 pin cable) and use them by leaving unsoldered one pin on both the mainboard and the IPS board (in doing this you have to leave unsoldered the first pin on a board and the last pin of the other one).

Production file

Download/produce them from PCBway

Additional info here.

Setup instructions

The most difficult parts of the project are the following:

• Desolder the components from the donor console by using a hot air gun. For this step, I suggest searching videos on youtube regarding the SYF Game Gear setup in which it is shown how to desolder the game gear CPU. Desoldering with a hot air gun became extremely easy if you use the adapters shown in the following image (search by using their codes on Aliexpress to find them).

  

• Drag soldering a 0.5 mm pitch SMD component. Also, in this case, you can refer to the videos made for the SYF Game Gear since solder the Game Gear single CPU version has the same type of difficulty.

These instructions must be integrated by watching and following the youtube videos presentation video and setup video.

First of all, you need to desolder a gameboy CPU from a gameboy DMG or from a super gameboy. Then, from a Gameboy DMG or from a DMG-07 adapter, you need to desolder the link port connector.

OPTIONAL: you can also desolder the power button (that can be reused or that can be internally restored), the 2 RAM chips, and the cartridge slot reader (both can be reused).

IMPORTANT: Please be sure that the following connections are properly made:

• STEP 1 (OPTIONAL): Restore the power button (see the setup video from 00:54 to 06:38).

  Tip: Differently from the video, you can use the brand new power switch directly (you find it in the BOM file) because a perfect combination between the original and the new switches is very hard to obtain. If you use the new button reported in the BOM file, firstly, it is not required to shorter the black plastic, and then, to make it all good, you can add a little tape, as shown in the following photos, to fit the space better.

  

• STEP 2: Populate the power board (see the setup video from 06:39 to 13:28).

  

• STEP 3: Populate the mainboard.

  • First, start with the components required to test only the power board and the battery charging circuit (see the setup video from 13:28 to 19:45).
  • Then, test the power board and the battery charging circuit (see the setup video from 19:45 to 23:19). If the RED or GREEN LED doesn’t work probably, you have installed it in the wrong orientation.
  • Once verified that the previous steps are OK, you can populate the mainboard entirely in a standard way (check the setup video from 23:19 to 24:42 to understand how to solder some components in the correct location).

  • Check the installation and the various switches (see the presentation video from 03:11 to 05:00) without the audio board just to be sure that the first 2 boards are ok. NOT exceed 6v (I suggest using 5v) power supply; otherwise, you will fry the TP4056 charger chip (only this chip will be damaged if you provide a voltage until 24v.In any case, use 5v!!!).

    

• STEP 4: Populate the audio board.

  • Populate entirely the audio board paying attention to the inductances L1, L2, and L3 (they are very fragile). In addition, the location of the electrolytic capacitors must be very accurate.
  • Choose the R2, R4 resistors for the speaker that you want to use (the original 0.25w speaker or the 1w speaker).
  • Solder the 2 little PCB to add thickness (see the setup video from 25:03 to 28:58).
  • Optional (also populate the pro-sound board and solder its 2 little PCBs for the thickness).

  • Check the audio board and the switch on the mainboard to turn ON/OFF the audio amplifier (once assembled, the console this switch can be used from the battery compartment. This can be useful to save battery by disabling the audio amplifier or to use the pro-sound jack always by disabling the audio amplifier).

    

• STEP 5: Populate the IPS board.

  • Firstly, you can populate the IPS board entirely by skipping soldering the button LEDS, the button resistors, and the contrast wheel (see the setup video from 28:58 to 29:55). Here on the power board, you can turn off the unregulated voltage required only with the original LCD.
  • Then, you can solder and test the contrast wheel (also required to change the settings of the IPS panel) (see the setup video from 29:55 to 33:30). In the video has been used an old version of the board having problems with the holes for the LED (now don’t worry about this since it has been fixed).
  • Then, you can install LED buttons, LED resistors, and the switch to turn ON/OFF these LEDs (see the setup video from 33:30 to 35:01).

  • Finally, test the buttons and their LEDs.

    

  • Pay attention to the orientation of the tactile buttons (the circled part of the following image must stay on the left and right for all the tactiles and not on the upper or lower part).

    

• STEP 6: Clean all the boards from flux and assembly the board (see the setup video from 36:28 to 42:20). Remember to properly set the switches for various options: bivert chip ON/OFF, normal video signal or biverted video signal, 0.5 A or 1 A charger, unregulated voltage (used only by the original LCD) ON/OFF, button LEDs on the IPS board ON/OFF.

WARNING Don't do a bath of 15/30 minutes for the IPS board if tactiles are installed (keep them outside the IPA; otherwise, the glue that keep metal pieces will be dissolved and switches break). I solder the tactiles after the bath in IPA without using additional flux (I simply exploit the flux of the soldering tin).

SUGGESTED ITEMS: I suggest using a 5v 2A USB-C charger with the adapter shown in the following image to play while charging at 1A. I suggest you buy a 125054 Lipo battery that has a perfect fit into the shell.

Finally, I suggest to use full silicone buttons from Kitsch-Bent as shown in this short video.

NOTE: When you start to hear aliens coming from the speaker and the screen starts flashing, it means that you have to charge the battery. I have not disabled the CPU in this case to give you the time to attach the power supply without losing the game in progress!!!

Material saving

If you plan to use an IPS board:

• you can skip solder/buy components for the -21V line required by the original LCD. These components on the power board are: F1, D3, D4, C11, C12, C13, C14, C15, C19, U6, and TR1. Clearly, you can also skip soldering the switch that enables/disables this -21V line.
  • you can use a 1.25 mm pitch 22-pin FPC connector (on both mainboard and IPS PCB) and connect them with a 22 FFC-pin connector if you have a problem finding the 21-pin cables and connectors (clearly, when soldering, you will solder only 21 pins and one remain floating).

FAQs

link here.

Troubleshooting

link here.

Acknowledgements

I would like to thank Mathijs (the creator of SYF Game Gear PCBs) for his several suggestions, schematics, and help in this project.

License

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. You are able to copy and redistribute the material in any medium or format, as well as remix, transform, or build upon the material for any purpose (even commercial) - but you must give appropriate credit, provide a link to the license, and indicate if any changes were made.

Support VIS projects

I have several stuffs in mind, but since developing these things has a high cost in materials and prototypes, a little PayPal donation is appreciated.

Contacts

email: vis.modding@gmail.com

discord: you can find me as vis_modding on several servers (BennVenn, Mouse Bit Lab, Retrosix modding, Game Boy, Gameboy makers, Cybdyn Systems, Pixel FX Official Discord, Modded Gameboy Club).