TTL
From uCtrl.net
Information
Transistor-Transistor Logic is a class of digital circuits were the logic gating function and amplifying is performed by transistors. It's a widespread intergrated curcuit used in many applications. The designation TTL is sometimes used to signify TTL-compatible logic levels, even when not associated directly with TTL integrated circuits, for example as a label on the inputs and outputs of electronic instruments. All standardized common TTL circuits operate with a 5-volt power supply. A TTL input signal is defined as "low" when between 0 V and 0.8 V with respect to the ground terminal, and "high" when between 2.2 V and 5 V.
