Dram chips

[Sky King]

I have some older circuits (from the '80) that I would like to build.
The logic chips are still available. I have one that uses 8-4164
drams and one that uses 2-41464 drams. I can expand the ram the
circuits uses to make them faster. If I swap the 4164's with 41256's
will that work? Or if I swap the 41464's with 414256's will that
work?

Thank you for helping me out with any info.

Thanks,
Sky King

 

[Lord Garth]

I have some older circuits (from the '80) that I would like to build.
The logic chips are still available. I have one that uses 8-4164
drams and one that uses 2-41464 drams. I can expand the ram the
circuits uses to make them faster. If I swap the 4164's with 41256's
will that work? Or if I swap the 41464's with 414256's will that
work?

Thank you for helping me out with any info.

Thanks,
Sky King

You'll have additional address lines for the deeper memory and likely
not for the wider memory. Most of these are CAS only refresh...be
sure the counter for the columns is the correct number of bits wide and
the correct depth to properly refresh the array or you'll have no
reliability. Don't forget decoupling capacitors near every IC.

 

[Sky King]

You'll have additional address lines for the deeper memory and likely
not for the wider memory.  Most of these are CAS only refresh...be
sure the counter for the columns is the correct number of bits wide and
the correct depth to properly refresh the array or you'll have no
reliability.  Don't forget decoupling capacitors near every IC.

Thanks for the info. I will have to check the refresh rate. Thanks
again.