Editing Clock signal (section)

{{Short description|Timing of electronic circuits}}
[[File:Clock signal.png|thumb|Clock signal and legend]]
In [[electronics]] and especially synchronous [[digital circuit]]s, a '''clock signal''' (historically also known as ''logic beat'')<ref name="Ferranti_1968"/> is an electronic [[logic signal]] ([[voltage]] or [[electric current|current]]) which oscillates between a high and a low state at a constant [[frequency]] and is used like a [[metronome]] to synchronize actions of digital [[Electronic circuit|circuits]].  In a [[synchronous logic]] circuit, the most common type of digital circuit, the clock signal is applied to all storage devices, [[Flip-flop (electronics)|flip-flop]]s and latches, and causes them all to change state simultaneously, preventing [[race condition]]s.  

A clock [[Signal (electrical engineering)|signal]] is produced by an [[electronic oscillator]] called a [[clock generator]].  The most common clock signal is in the form of a [[Square wave (waveform)|square wave]] with a 50% [[duty cycle]].   Circuits using the clock signal for synchronization may become active at either the rising edge, falling edge, or, in the case of [[double data rate]], both in the rising and in the falling edges of the clock cycle.