Editing 555 timer IC (section)

{{Short description|Integrated circuit used for timer applications}}
{{Lead too short|date=January 2024}}
{{Infobox electronic component
|name           = 555 timer IC
|image          = Signetics NE555N.JPG
|image_size     = 250
|caption        = [[Signetics]] NE555 in 8-pin [[Dual in-line package|DIP package]]
|type           = [[Passivity (engineering)|Active]], [[integrated circuit]]
|invented       = [[Hans Camenzind]] (1971)
|first_produced = 1972
|symbol         = [[File:555 esquema.png|250px]]
|symbol_caption = Internal block diagram<ref name="TI_NE555_Datasheet"/>
}}

The '''555 timer IC''' is an [[integrated circuit]] used in a variety of [[timer]], delay, pulse generation, and [[Electronic oscillator|oscillator]] applications. It is one of the most popular timing ICs due to its flexibility and price. Derivatives provide two ([[#556 dual timer|556]]) or four ([[#558 quad timer|558]]) timing circuits in one package.<ref name="Signetics_1985_Linear_Databook"/> The design was first marketed in 1972 by [[Signetics]]<ref name="EEtimes_20120815">{{cite news|last1=Fuller|first1=Brian|date=15 August 2012|title=Hans Camenzind, 555 timer inventor, dies|work=EE Times|url=http://www.eetimes.com/document.asp?doc_id=1262353|access-date=27 December 2016}}</ref><ref name="Signetics_1972_Linear1_Databook" /> and used [[bipolar junction transistor]]s. Since then, numerous companies have made the original timers and later similar low-power [[CMOS]] timers. In 2017, it was said that over a billion 555 timers are produced annually by some estimates, and that the design was "probably the most popular integrated circuit ever made".<ref name="Dummies">{{Cite book|last=Lowe|first=Doug|url=https://books.google.com/books?id=Ivn-DQAAQBAJ&pg=PA339|title=Electronics All-in-One For Dummies|date=2017-02-06|publisher=Wiley |isbn=978-1-119-32079-1|pages=339|quote=The 555 timer chip, developed in 1970, is probably the most popular integrated circuit ever made. By some estimates, more than a billion of them are manufactured every year.}}</ref>