විස්තරයTexasInstruments 7400 chip, view and element placement.jpg
English: The view and element placement of the popular chip 7400. The chip contains four logical elements AND-NOT (NAND). The two additional contacts supply power (+5 V) and connect the ground. This chip was made in the 45th week of 1976.
The former Soviet Union manufactured the analog K155ЛA3, where even contacts were placed identically (the voltage supply was also + 5 V, so at least in some cases the chips were replaceable). It was a very popular chip, widely used by amateurs.
The view and element placement of the popular chip 7400. The chip contains four logical elements AND-NOT (NAND). The two additional contacts supply power (+5 V) and connect the ground. Literature *http://opencircuitdesign.com/xcircuit/tutorial/tutorial2.