Logic gate (nonfiction): Difference between revisions

From Gnomon Chronicles
Jump to navigation Jump to search
No edit summary
Line 1: Line 1:
[[File:LogicGatesWorking.png|thumb|Logic gates. The AND gate is False; the OR gate is True.]]In electronics, a '''logic gate''' is an idealized or physical device implementing a Boolean function.
[[File:LogicGatesWorking.png|250px|thumb|Logic gates. The AND gate is False; the OR gate is True.]]In electronics, a '''logic gate''' is an idealized or physical device implementing a Boolean function.


That is, it performs a logical operation on one or more logical ''inputs'', and produces a single logical ''output''.
That is, it performs a logical operation on one or more logical ''inputs'', and produces a single logical ''output''.


== Description ==
All of the principles of [[Boolean logic (nonfiction)|Boolean logic]] can be expressed as logic gates.
 
Depending on the context, the term may refer to an ideal logic gate, one that has for instance zero rise time and unlimited fan-out.
 
Or, it may refer to a non-ideal physical device (see Ideal and real op-amps for comparison).
 
== Implementation ==
 
Logic gates are primarily implemented using diodes or transistors acting as electronic switches, but can also be constructed using vacuum tubes, electromagnetic relays (relay logic), fluidic logic, pneumatic logic, optics, molecules, or even mechanical elements.
 
== Boolean logic ==
[[File:LogicGates.jpg|thumb|Logic gate chart.]]
All of the principles of [[Boolean logic]] can be expressed as logic gates.


With amplification, logic gates can be cascaded in the same way that Boolean functions can be composed, allowing the construction of a physical model of Boolean logic.
With amplification, logic gates can be cascaded in the same way that Boolean functions can be composed, allowing the construction of a physical model of Boolean logic.


In principle, any [[algorithm]] can be expressed as logic gates.
In principle, any [[Algorithm (nonfiction)|algorithm]] can be expressed as logic gates.


== Devices ==
In reversible logic, [[Toffoli gates]] are used.


Logic circuits include such devices as multiplexers, registers, arithmetic logic units (ALUs), and computer memory, all the way up through complete microprocessors, which may contain more than 100 million gates.
== In the News ==


In modern practice, most gates are made from field-effect transistors (FETs), particularly MOSFETs (metal–oxide–semiconductor field-effect transistors).
<gallery mode="traditional">
File:LogicGates.jpg|Logic gate chart.
</gallery>


== Compound logic gates ==
== Fiction cross-reference ==
 
Compound logic gates AND-OR-Invert (AOI) and OR-AND-Invert (OAI) are often employed in circuit design because their construction using MOSFETs is simpler and more efficient than the sum of the individual gates.
 
== Reversible logic and Toffoli gates ==
 
In reversible logic, [[Toffoli gates]] are used.


== Nonfiction cross-reference ==
== Nonfiction cross-reference ==
Line 39: Line 23:
* [[Toffoli gate (nonfiction)]]
* [[Toffoli gate (nonfiction)]]


== Fiction cross-reference ==
External links:
 
==  External links ==


* [http://wiki.karljones.com/index.php?title=Logic_gate Logic gate] @ wiki.karljones.com
* [http://wiki.karljones.com/index.php?title=Logic_gate Logic gate] @ wiki.karljones.com
* [https://en.wikipedia.org/wiki/Logic_gate Logic gate] @ Wikipedia
* [https://en.wikipedia.org/wiki/Logic_gate Logic gate] @ Wikipedia





Revision as of 16:29, 23 June 2016

Logic gates. The AND gate is False; the OR gate is True.

In electronics, a logic gate is an idealized or physical device implementing a Boolean function.

That is, it performs a logical operation on one or more logical inputs, and produces a single logical output.

All of the principles of Boolean logic can be expressed as logic gates.

With amplification, logic gates can be cascaded in the same way that Boolean functions can be composed, allowing the construction of a physical model of Boolean logic.

In principle, any algorithm can be expressed as logic gates.

In reversible logic, Toffoli gates are used.

In the News

Fiction cross-reference

Nonfiction cross-reference

External links: