The 7400 series is a popular logic family of transistor–transistor logic integrated circuits.
The SN7400N chip contains four two-input NAND gates. The SN prefix indicates it was manufactured by Texas Instruments. The N suffix is a vendor-specific code indicating plastic DIP packaging. The second line of numbers (7645) is a date code; this chip was manufactured in the 45th week of 1976.
Texas Instruments SN5451 in the original flat package
Die of a 74AHC00D, manufactured by NXP
SN7400 die in the original flat package, manufactured by TI
The 4000 series is a CMOS logic family of integrated circuits first introduced in 1968 by RCA. It was slowly migrated into the 4000B buffered series after about 1975. It had a much wider supply voltag
7400-series integrated circuits
…CMOS technology or a combination of the two (BiCMOS). Originally the bipolar circuits provided higher speed but consumed more power than the competing 4000 series of CMOS devices. Bipolar devices are also limited to a fixed power-supply voltage, typically 5 V, while CMOS parts often support a range of supply…
CD4007A on a solderless breadboard
A very early CD4029A counter IC, in 16-pin ceramic dual in-line package (DIP-16), manufactured by RCA
Colorized IC die and schematics of CD4011BE NAND gate
CD4001B in DIP-14 package (quad 2-input NOR gate)