Mortal Kombat II CMOS RAM LH5268A-10LL equivalent

[marcus.miranda]

Hello!

I have a MK2 board I "rescued" from the grave that's giving me the "CMOS CHIP U49 BAD" error message and does not hold any configuration.
It's presenting two "funny" glitches:
1) It will not enter the "game adjustments" section under the service menu.
2) It will not hold coin numbers after each versus battle
- often showing weird number like 1/255 or 30 (maximum reached) even though I didn't "insert" any new coin.

I changed the battery since the old one was measuring 2.8v to no success. Also, I can trace the 3.3v to the UH6 pin 1 successfully but the configuration are not being stored and the message persists at every boot.

I noticed the CMOS RAM chip at UJ11 (Sharp LH5268A-10LL) has some of its pins oxidized.
Pins 10 and 11 are slightly oxidized, and the pins 15 and 16 are heavily oxidized (tried co capture it on a picture but it doesn't show how it really is).


So I am looking for an equivalent for this IC since it's a 64k CMOS RAM (8k x 8).
Can I use a Toshiba TC5565APL-10 instead or any other else?

Thanks!

 

[mecha]

that oxidation is nothing. did you replace the CMOS battery? if the CMOS has no power when the game is off, it will erase. when you replace the battery measure the voltage at the + and - points on the underside of the board. if you have no voltage, then the battery holder is dirty.

 

[marcus.miranda]

that oxidation is nothing. did you replace the CMOS battery? if the CMOS has no power when the game is off, it will erase. when you replace the battery measure the voltage at the + and - points on the underside of the board. if you have no voltage, then the battery holder is dirty.

yup!
I didn't have a 2325 but put a 2032.
I can measure the 3.2v in MAX691 pin 1 but the U49 error persists.
I removed the UJ11 and put a socket in its place... found a brand new LH5268A-10LL laying around here and will test it.
I also removed UG12 and UJ12 for cleaning since UJ11 talks to UJ12 and will try the board today.

Thx for the tips!