Editing Transistor–transistor logic (section)

{{Short description|Class of digital circuits}}
'''Transistor–transistor logic''' ('''TTL''') is a [[logic family]] built from [[bipolar junction transistor]]s (BJTs). Its name signifies that transistors perform both the logic function (the first "transistor") and the amplifying function (the second "transistor"), as opposed to earlier [[resistor–transistor logic]] (RTL) and [[diode–transistor logic]] (DTL).

TTL [[integrated circuit]]s (ICs) were widely used in applications such as [[computer]]s, industrial controls, test equipment and instrumentation, consumer electronics, and [[synthesizer]]s.<ref>{{citation |last=Eren |first=H. |title=Electronic Portable Instruments: Design and Applications |publisher=CRC Press |year=2003 |isbn=0-8493-1998-6 |url=https://books.google.com/books?id=xwfpvzvNTr4C&pg=PA353 }}</ref>

After their introduction in integrated circuit form in 1963 by [[Sylvania Electric Products]], TTL integrated circuits were manufactured by several semiconductor companies.  The [[7400 series]] by [[Texas Instruments]] became particularly popular. TTL manufacturers offered a wide range of [[logic gate]]s, [[Flip-flop (electronics)|flip-flops]], counters, and other circuits. Variations of the original TTL circuit design offered higher speed or lower power dissipation to allow design optimization. TTL devices were originally made in ceramic and plastic [[dual in-line package]](s) and in flat-pack form. Some TTL chips are now also made in [[surface-mount technology]] packages.

TTL became the foundation of computers and other digital electronics. Even after [[Very-Large-Scale Integration]] (VLSI) [[CMOS]] integrated circuit [[microprocessor]]s made multiple-chip processors obsolete, TTL devices still found extensive use as [[glue logic]] interfacing between more densely integrated components.