Digital Circuits/AND gate

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AND gates is one the basic gates used to implement logical conjunction. It is basically a multiple input gate with a single output.

Electrical Analogy[edit]

It is analogous to a pair of switches in series which operates a bulb which is again in series with these switches. Thus, the bulb will be ON only when both the switches are closed. As seen from the truth table of an AND gate, the output will be HIGH only when all of its inputs are in logical 1 state.

Standard Symbols[edit]

AND ANSI.svg AND IEC.svg AND DIN.svg
MIL/ANSI Symbol IEC Symbol DIN Symbol

Design using MOSFETs[edit]

NMOS AND gate

The adjoining logic diagram shows the construction of an AND gate using N-Channel MOSFET. Alternatively, an AND gate can also be constructed using P-Channel MOSFET.

Truth Table[edit]

A B Q
0 0 0
0 1 0
1 0 0
1 1 1