Editing Logic family (section)

==Resistor–transistor logic (RTL)==
{{Main|Resistor–transistor logic}}

Class of [[digital circuit]]s built using [[resistor]]s as the input network and [[bipolar junction transistor]]s (BJTs) as switching devices.

The [[Atanasoff–Berry Computer]] used resistor-coupled [[vacuum tube]] logic circuits similar to RTL. Several early [[transistor]]ized computers (e.g., [[IBM 1620]], 1959) used RTL, where it was implemented using discrete components.

A family of simple resistor–transistor logic integrated circuits was developed at [[Fairchild Semiconductor]] for the [[Apollo Guidance Computer]] in 1962. [[Texas Instruments]] soon introduced its own family of RTL. A variant with integrated capacitors, RCTL, had increased speed, but lower immunity to noise than RTL. This was made by Texas Instruments as their "51XX" series.