DS1250AB Nonvolatile SRAM reliability

[Lawrence101]

Hi folks, just re-joined. I have a couple of DS1250AB Nonvolatile sram ic'c that i got from Dallas semiconductor over 10 years ago, was planning on using one of them in a circuit i but concerned about its reliability. havent looked at the data sheet in awhile but i believe its internel batttery has a life expectancy of 10 years ? Anyone have any experience in use these or something similar ? I saw something awhile back of a guy that used a dremel tool to cut the package open to replace the battery, or should i just toss it in the garbage ?

 

[Pommie]

I wrongly assumed it was a Dallas One Wire device but looking at the datasheet I see it's got full address and data lines. I did notice in the datasheet this line,

• Lithium energy source is electrically disconnected to retain freshness until power is applied for the first time

Not sure how that works but it may be worth trying to power it up.

It also states,

• Replaceable snap-on PowerCap provides lithium backup battery

Again, not sure what that means.

Mike.

 

[Nigel Goodwin]

If it's ten years old, and the expected battery life is ten years - it doesn't really matter if it's been used or not, the ten years is presumably the shelf life of the battery. It 'might' be OK to 'play with', but it's unlikely to be worth using in an actual project, I would expect battery failure isn't far away (assuming it's not dead already).

Years ago, in an early PC, I added a similar style battery backed clock module with built-in maintained RAM - it plugged in a DIL socket on the motherboard. That too had a similar estimated life - and it died around that time.

 

[Lawrence101]

Thanks for replying guys very helpful.

I wrongly assumed it was a Dallas One Wire device but looking at the datasheet I see it's got full address and data lines. I did notice in the datasheet this line,

• Lithium energy source is electrically disconnected to retain freshness until power is applied for the first time

Not sure how that works but it may be worth trying to power it up.

It also states,

• Replaceable snap-on PowerCap provides lithium backup battery

Again, not sure what that means.

Mike.

Mike , yes thats about my understanding of it as well. i posted a comment on the guys video and he said much the same thing i.e connect it in a circuit and see what happens.

Nigel, Yes i was concerned it might work for a short while and die, i doubt DS has them anymore ( obsolete part ) , hate to just throw it out, for nostalgia reasons ( only electronics enthusiasts will understand ) . I'll plug it into my BB and power it up when i get around to it, will post if it works or not.

Lawrence

P.S. I beleive it will still work even if the internal battery is dead ? if its sole purpose was for data retention ? Guess it would then be a volatile sram.

 

[Nigel Goodwin]

P.S. I beleive it will still work even if the internal battery is dead ? if its sole purpose was for data retention ? Guess it would then be a volatile sram.

I would have thought so, it's essentially just a static ram and a battery.