Tatsujin Oh repair log #2

Another board from the ‘portughese’ box : Tatsujin Oh, a great shoot ’em up released by Toaplan and known outside Japan as Truxton II.

Board was booting but sprites were mostly missing and other GFX glitches present too:

There was an obvious reason of this.The custom ASIC  ‘GP9001’ (which is the graphics controller of the system) was damaged : some pins were missing, other bridged, two traces going to it were ripped too.

Here’s a close-up under a microscope:

Given the extent of the damage the only possible solution was the replacement of the ASIC which is a very delicate operation (not for everyone…) because of  its package (208 pins in a QFP package with very fine pitch).For this purpose I’ve been sent by the owner a dead FixEight PCB as donor:

I removed the damaged part and cleaned the area preparing it for the trasplant:

The spare removed from the donor board :

After soldered it I took care of rebuilding the ripped traces using some AWG30 wire :

Testing was successful, board 100% fixed.