Anybody w/ 512x8 Proms?
en
Anybody have any? And, does anyone have a datsheet on these?
I've got the NS 1985 databook w/ the 74S472.
AMD = 27S29
MMI = 6349-1 , 6349-2 , 63S481
Motorola/Harris = 7649-5 , 7645A-5
Nat. Semi. (1985 datasheet) = 74S472 or 74S472A
NEC = UPB424
Raytheon = 29621 , 29621A
Signetics = 82S147 or 147A
TI = 28S42 , 18S42
.
news:3E4E0F2E...@sprintmail.com...
I checked on these numbers and basically verified that they all cross to
each other.
My best results came from an 1984 vol. 1 IC Master. There are two pages of
ordering
data and cross ref. numbers on the TI part 28S42. I can scan and email them
to you if
you like. Unfortunately, most other part numbers have info in 1984 vol. 2
IC Master
which I don't have.
I've had limited success finding datasheets using partminer:
http://www.freetradezone.com/ (requires login)
Some potential sources for these parts are listed below. I deal with
military electronics so
obsolescence is a constant problem. If anyone else in this NG knows of
obsolete part
sources please post them whether or not they're mil.
Obsolete military electronic parts links:
http://www.atradeworld.com/ (requires login)
http://www.expediters.com/
http://www.militarycomponents.com/
http://www.electrospec-inc.com/
http://www.gauinc.com/
http://www.harrykrantz.com/
http://www.lansdale.com/
http://www.linearsystems.com/
http://www.lukechips.com/
http://www.icparts.com/
http://www.nevratech.com/
http://www.nowelectro.com/
http://www.omegacomponents.com/
http://www.qp-labs.com/
http://www.rocelec.com/
http://www.tweusa.com/
Long shots:
I suppose you could check ebay but I find it usually isn't worth the trouble
for obsoletes.
There is also http://www.ioffer.com/ which originated as
http://www.ewanted.com/.
en
> "en" <en...@sprintmail.com> wrote in message
> news:3E4E0F2E...@sprintmail.com...
> > Hi, I'm looking for some old schottky bipolar proms.
> > Anybody have any? And, does anyone have a datsheet on these?
> > I've got the NS 1985 databook w/ the 74S472.
> > AMD = 27S29A
> > MMI = 6349-1 , 6349-2 , 63S481
> > Motorola/Harris = 7649-5 , 7645A-5
> > Nat. Semi. (1985 datasheet) = 74S472A
> > NEC = UPB424
> > Raytheon = 29621A
> > Signetics = 82S147A
> > TI = 28S42 , 18S42
> I checked on these numbers and basically verified that they all cross to
> each other. My best results came from an 1984 vol. 1 IC Master. There
> are two pages of ordering data and cross ref. numbers on the TI part 28S42.
> I can scan and email them to you if you like. Unfortunately, most other
> part numbers have info in 1984 vol. 2 IC Master ... snip ...
Hi, I went to opamp books and found a '84 IC Master. The cross is ok, but
there's a problem between AMD and National Semi. NS has a faster Access time,
and is 5ns faster than the AMD. I'll have to find as many of the datasheets
as I can before I start buying.
from AMD databook, 1986, Bipolar/MOS Memories
AM27S29A , 4096-bit, (512x8) Bipolar PROM
Tri-state
Address Access Time 35ns
Delay from Output Enable Valid to Output Hi-Z 20ns
Delay from Output Enable Valid to Output Valid 20ns
from the National Semiconductor, 1985 Databook
DM74S472A (512x8) 4k-bit TTL PROM
Address Access Time 25ns
Enable Access 15ns
Enable Recovery 15ns
thanks
Ed