NAND gate

NAND gate truth table
Input		Output
A	B	A NAND B
0	0	1
0	1	1
1	0	1
1	1	0

A NAND (NOT AND) gate is a logic gate which produces an output which is false only if all its inputs are true; thus its output is complement to that of an AND gate. A LOW (0) output results only if all the inputs tot he gate are HIGH (1); if any input is LOW (0), a HIGH (1) output results. A two-input NAND gate's logic may be expressed as $\bar{A}\vee \bar{B}=\overline{A\cdot B}$, making a NAND gate equivalent to inverters followed by an OR gate.

The NAND gate is significant because any Boolean function can be implemented by using any combination of NAND gates. This property is called "functional completeness". It shares this property with the NOR gate.

Symbols

ANSI Symbol

ANSI Symbol

IEC Symbol

IEC Symbol

Integrated Circuits

Some common implementations of the NAND gate as integrated circuits:

Name	Description
CMOS
4011	Quad 2-Input NAND gate
4012	Dual 4-Input NAND gate
4023	Triple 3-Input NAND gate
4068	Mono 8-Input NAND gate
TTL
74x00	Quad 2-Input NAND gate
74x10	Triple 3-Input NAND gate
74x20	Dual 4-Input NAND gate
74x30	Mono 8-Input NAND gate

See also

• AND gate
• NOR gate
• NOT gate
• OR gate
• XNOR gate
• XOR gate