Hello all,
I am studying electronics at college and have been asked to compare the TTL Low Power Schottky (74LS) and CMOS (4000B) logic families.
I have searched the internet for figures to compare but it seems that everywhere I look gives different values for the specifications that I require. Would any of you be able to give me general values for the:
-Logic high and Logic Low Input current and ‘Fan In’
-Logic high and Logic Low Output current and ‘Fan Out’
-Propagation Delay
-Noise Margin
-Logic high and Logic Low input voltage levels
-Logic high and Logic Low output voltage levels
-Upper frequency limit
for each of the TTL Low Power Schottky (74LS) and CMOS (4000B) logic families so that I can then compare them to each other to create my answer.
I understand these values may be slightly different for different logic chips and manufacturers but I am just after a general overview. Component datasheets don’t seem to give all the information that I require and they are all rather cryptic about some points as I guess these values are presumed by the fact they are members of these logic families.
Any help would be amazing.
Thanks