View Full Version : raplcement chip question

25th May 2006, 10:21 AM
Hi there

I am repairinga terra force board with gabled grpahics

I think the TMM2064p-15 RAM might be bad

It is a 64K static MOS RAM - For the life of me I cannot find any
cross-reference info (not in my paper ECG guide or online). Even the Toshiba site has nothing.

Toshiba released a pin compatible 64K static CMOS Ram, the TC5564. I
have found lots of cross reference material for this chip.

Can i use this TC5564 or its equivalents instead?

Am i being too naive and simplistic. Apart from the MOS/CMOS
difference, I cannot find any real difference on their datasheets?

Thanks for your help


25th May 2006, 01:16 PM
Ric the 5564 will do the same job ,

the 2064 is very common , when searching for information take the TMM , p and other information off , the TMM will limit your search to only that manufacturer.

EG: if you google for TMM2064 CMOS Ram you will get about 4 hits
If you google for 2064 CMOS Ram you will 15,700 hits :)

25th May 2006, 01:58 PM

thanks for that

I have just started to do board repair for pcbs and have found chip cross-referencing to be the hardest part so far


27th May 2006, 03:36 AM

The chipr directory . A good information database.

Chip Numbering 101 :)

Most of the time, only the numbers are really important, althought on any of the 74 series, you have to know what you are doing to substitute another class of chip there. All got to do with how many other gates it needs to drive plus distance, timing, or one oth those bloody pcb's that has to have the same type chip. Grrrr.