7427

The 7427 (variants 74LS27, 74HC27) is a 74-series logic IC with three independent 3-input NOR gates.

7427 Pinout

       .--\/--.
 1A -> |01  14| -- +5V
 1B -> |02  13| <- 1C
 2A -> |03  12| -> 1Y
 2B -> |04  11| <- 3C
 2C -> |05  10| <- 3B
 2Y <- |06  09| <- 3A
Gnd -- |07  08| -> 3Y
       `------'

Signal descriptions

Y is high if all of A, B and C are low. Y is low if any of A, B or C is high.

References

• GIICM – 7400 series TTL IC's: 7400...7449