original 7409 logic chips

rwgast_logicdesign

so ive been sorting a huge pile of logic chips most are all ttl 74sl which kind of sucks but they should work fine with a bs2 or arduino as far as learning and expermenting goes.

I also have some waaay old chips the 4000 cmos kind and the 7400 series ie 7402 no letters original logic family. I looked at a data sheet for a plain 7402 chip on digikey and idk if im reading it right but the switching speed is 3.5 to 12ns???? that seems reasonably fast am i just reading this wrong

http://www.ti.com/lit/ds/symlink/sn7402.pdf

frank freedman

Sorta. The letter designation was a sub family of the original 7400 series. Figure optimized for certain trade offs. The letter tells which. The LS was for reduced power needs, the trade was slower Tpd. The S series as you have seen went in for speed, so fast yes, but a bit power hungry. Get hold of the TI logic family handbook. It is all on there.

FF

RDL2004

I think this TI Logic Guide is the one Frank is talking about. He posted the link in one of your other threads. It's one of the best I've seen.