2116 and other old memory chips

I don't think the 2116's (now, this is from memory cells undisturbed in probably 20 years ... so be careful ... ) are much different from 2117's, which I've routinely interchanged and mixed with 4116's. The 2114's are single-supply 1Kx4-bit SRAMs, while the 2116's are dynamic and 3-rail. The single supply Intel 16-kbit DRAMs are the 2118's. The TI number for the 2114's was TMS-4045 and other vendors had part numbers similar to the 2114, e.g. 9114, 7114, etc. National had a 5290 instead of the 4116 designation, but the parts were similar. There are some "special" parts that need to be noted, particularly the 4115, from Mostek. These were devices the gate capacitance of which wasn't enough to hold their charge reliably for the entire 2 ms refresh interval, so they had the special designation of 4115 to indicate they required more frequent refresh, which often wasn't an issue, since they were used in applications where they were cycled very frequently because of video refresh or other system activities that cycled the row addresses faster than the 2 ms per 128-byte cycle requirement of 4116's. Intel's memory numbering was a mite confusing, as they had an old SRAM line with numbers like 2115 and 2125, which were 1kx1 fast (15-25 ns) srams while the 2114's were slow 1kx4's. They had lots of numbers, and the numeric series designation was often not at all indicative of the nature of the part. I've still got quite a few 4116's (200 ns Tacc, mostly) that I'll donate for the cost of shipping, to folks with REAL applications for them. I'm not interested in shipping them in quantity to folks building pop-art with 'em, however, as these work, and they don't make 'em anymore. Dick ----- Original Message ----- From: "Louis Schulman" <louiss(a)gate.net> To: <classiccmp(a)classiccmp.org> Sent: Friday, July 06, 2001 5:54 PM Subject: 2116 and other old memory chips