Basic Logic Gates

Type

Circuit Symbol

Boolean algebra

Truth table

AND

AND symbol

AB

INPUT

OUTPUT

A

B

A AND B

0

0

0

0

1

0

1

0

0

1

1

1

OR

OR symbol

A+B

INPUT

OUTPUT

A

B

A OR B

0

0

0

0

1

1

1

0

1

1

1

1

NOT

NOT symbol

A

INPUT

OUTPUT

A

NOT A

0

1

1

0

NAND

NAND symbol

(AB)

INPUT

OUTPUT

A

B

A NAND B

0

0

1

0

1

1

1

0

1

1

1

0

NOR

NOR symbol

(A+B)

INPUT

OUTPUT

A

B

A NOR B

0

0

1

0

1

0

1

0

0

1

1

0