Digital Circuits/AND gate

From Wikibooks, open books for an open world
Jump to navigation Jump to search

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

Electrical Analogy[edit | edit source]

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 | edit source]

MIL/ANSI Symbol IEC Symbol DIN Symbol

Design using MOSFETs[edit | edit source]

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 | edit source]

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