Author Topic: Need help in finding BBSRAM replacement (decoding & comparing two datasheets)  (Read 2438 times)

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Online BravoVTopic starter

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Currently I'm looking for a possibility of a drop in replacement for the BBSRAM made by Maxim/Dallas DS1225Y with a F-RAM based memory made by Ramtron (Cypress Semi) FM1608-120-PG.

Both datasheets are attached below at this post.

I've checked both are pins compatible, also at the basic specification like the voltage rating and other basic operating conditions, its just I'm totally lost when it comes to comparing both at the AC timings and the logic conditions like for read or write activities.

I tried but still quite hard for me to make a conclusion if this F-RAM is suitable , also to be honest I'm kind of worry if I missed crucial details as Dave loves to say "trap for young player".  ???

Appreciate any helps, thanks in advance.
« Last Edit: April 04, 2013, 01:31:10 am by BravoV »
 

Online BravoVTopic starter

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Damn, finally found it myself, apparently this cool F-RAM just can't be plugged in to replace the pesky BBSRAM.  :'(

The DS1225Y only needs the Chip Enable (CE) pin to be enabled "once" for multiple read/write operations, while the FM1608 needs the CE to be "toggled" for every read/write, the memory address changed and latched on CE 's edge, not the state, what a bummer.  |O

Offline amyk

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Have you looked at the STK12C68?
 

Online BravoVTopic starter

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Have you looked at the STK12C68?
Yes, I've looked into that as well, but worry the complication on the Autostore feature at power up or down sequence.

Anyway, I've pulled the trigger on FM28V020-SG at Cypress Semi's store, after an intense reading and comparing them, even its 4 times bigger (32Kx8) vs (8Kx8), I'm planning to make a SOIC 28 to DIP adapter with a small DIP switch with 2 poles, soldered at the adapter for manually switching between 4 banks.

Theoretically, this should last for centuries.  :o

PS : This thread actually related to my other thread -> Here
« Last Edit: April 06, 2013, 06:09:53 am by BravoV »
 


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