Available replacement for SRAM HM62256BLFP (low standby power ~ 1uW)?

[carl_lab]

I try to find an available replacement for SRAM Hitachi HM62256BLFP (low standby power ~ 1uW +/-).
3V, 5V tolerant
2.7V data retention voltage

Datasheet of original:
http://ee-classes.usc.edu/ee459/library/datasheets/hm62256.pdf

Can anybody help?

[YTSOC]

why not just order it of ebay?

[carl_lab]

Can't buy from ebay by business account.

[ap]

Digikey e.g. has them, even lower typ. standby current.

[carl_lab]

Digikey e.g. has them, even lower typ. standby current.

Can you provide the link, please?

[JFJ]

The search results for SRAM 32K on the Farnell web site provides several equivalents to the Hitachi SRAM, e.g:

http://de.farnell.com/lyontek/ly62256sl-55lli/sram-256k-32kx8-2-7-5-5v-28soic/dp/2253655

[carl_lab]

Great, thank you!
Can I use faster than original (55ns instead of 70ns)?

[Tomorokoshi]

Great, thank you!
Can I use faster than original (55ns instead of 70ns)?

It should be fine when it comes to data access.

Note that there are other parameters that have timing changes. For instance, t_CHG and t_WHZ. However, these shouldn't be a problem unless it is being accessed by something outside of a typical processor given the (for these days) relatively slow access.

Also compare the output load rating to the original part. This one is listed as "C_L = 50pF + 1TTL". For instance, if the slower original is rated to 100pF for it's timing, etc. then it may all balance out anyway.

[JFJ]

Can I use faster than original (55ns instead of 70ns)?

The address access time quoted is the maximum access time (no minimum time is specified). The price for the 70ns version is exactly the same:

http://de.farnell.com/lyontek/ly62256sl-70ll/sram-256k-32kx8-2-7-5-5v-28sop/dp/2253657

That might suggest that the 55ns and 70ns versions are identical, with just the markings changed.

[carl_lab]

Also compare the output load rating to the original part. This one is listed as "C_L = 50pF + 1TTL".
For instance, if the slower original is rated to 100pF for it's timing, etc. then it may all balance out anyway.

Exactly!
Dataheet HM62256B:

HM62256B-5: 1 TTL Gate + C_L (50 pF)(Including scope & jig)
HM62256B-7/8:  1 TTL Gate + C_L (100 pF)(Including scope & jig)