41256 DRAMs discontinued?

[mikeb]

:idea:   :shock:  :?:  :twisted:  

[puretube]

...rumour has it, there are similar devices like the PT2395
(formerly produced by Mitsubishi - now discontinued by them...-)
out there, that can/need to address external RAMMMMM.

:?:

[wstephens]

All,

These 3 256k*1 dip16 DRAMs have matching pinouts. Would they work?

from Mouser:
NTE replacement Memory DRAM 256K/150 DIP-16 $9
http://www.nteinc.com/specs/21000to21999/pdf/nte21256.pdf

THis place has 3 41256  $2
http://www.weisd.com/store2/JSH41256-12-S.html

Jameco.com has 41256 (part no. 117659) for $.73 (and volume discounts)

Bill

[puretube]

hey, thank you, man!  

Welcome to the forum - been working thru all the back-threads?

[Peter Snowberg]

Welcome Bill.

Yes, those three should all function the same. SHOULD is the operative word.

With the 41256 was a generic part by the end of it's run and there were lots of sub-variants with different behavior for page mode, different refresh period, different setup times, etc. so most chips will work in most designs but it's not 100%.  Try to always go for the 120ns parts for maximum compatibility with everything. I seem to recall the 150ns parts being the more "unique" versions.

Back when those chips were more current, I bought quite a few from Jameco and never had a probelm with the devices I used them in. (I lived about 25km away from Jameco so I would order will-call constantly)

[wstephens]

Puretube,

Yeah, just catching up.  I joined a while back but haven't contributed much.  A long modulated delay is high on my want list.

Bill