Resistor-transistor logic
From Free net encyclopedia
Image:RTL npn nand.png Resistor-transistor logic (RTL) is a class of digital circuits built from bipolar junction transistors (BJT), and resistors; it is the earliest transistorized digital logic used. Its main limitation was its limited fanin, 3 inputs being the limit for many circuit designs, before it completely lost usable noise immunity.
See also: diode-transistor logic (DTL), transistor-transistor logic (TTL), emitter coupled logic (ECL), Integrated injection logic (I2L).