On Tue, 24 Feb 2015 14:43:10 +0800 Li Ang <lll...@gmail.com> wrote: > I saw people talking about using 74AC to square the signal, what's the > difference between 74LVC and 74AC? 74AC is not easy to get.
These are different families of chip production. You can see the 74HCxx as the grandfather, 74ACxx as the father and the 74LVCxx as the son. IIRC the AC (Advanced CMOS) was introduced in the 80s. The process which they were produced got superseeded and also the voltage levels went down. The LVC (Low Voltage CMOS) and LVX families are the current choice for logic gates. The main difference is that the node size (those nm measures people boast with, when they talk about chips these days) went down and with that the threshold voltage of the FETs and the maximum voltage the chips can withstand. Of course there are differences in the timing specs as well. TI's Logic Guide[1] and their Logic Migration Guide[2] contain additional information. Attila Kinali [1] http://www.ti.com/lit/sg/sdyu001aa/sdyu001aa.pdf [2] http://www.ti.com/lit/ml/scyb032/scyb032.pdf -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.