(TTL) A common semiconductor technology for building discrete digital logic integrated circuits. It originated from {Texas Instruments} in 1965. There have been several series of TTL logic: 7400: 10 ns propagation time, 10 mW/gate power consumption, obsolete; 74L00: Low power: higher resistances, less dissipation (1 mW), longer propagation time (30 ns); 74H00: High power: lower resistances, more dissipation: less sensitivity for noise; 74S00: Schottky-clamped: faster switching (3 ns, 19 mW) by using Schottky diodes to prevent the transistors from saturation; 74LS00: Low power, Schottky-clamped (10 ns, 2 mW); 74AS00: Advanced Schottky: faster switching, less dissipation, (1.5 ns, 10 mW); 74ALS00: Advanced Low power Schottky (4 ns, 1.3 mW). For each 74xxx family there is a corresponding 54xxx family. The 74 series are specified for operation at 0 - 70 C whereas the 54 (military) series can operate at -55 - 125 C See also CMOS, ECL.

Low Voltage Transistor Transistor Level (Reference: IC)

Transistor–transistor logic (TTL) is a logic family built from bipolar junction transistors. Its name signifies that transistors perform both the logic function (the first "transistor") and the amplifying function (the second "transistor"), as opposed to resistor–transistor logic (RTL) or diode–transistor logic (DTL).