Why digital signals & circuits? Noise immunity of Digital circuits /Ideal & practical inverter (NOT gate) characteristics. Simple resistive-load (RTL) inverter /Static & dynamic behavior & parameters of an inverter /Various logic gate realizations (RTL, TTL, nMOS, CMOS, BiCMOS) and their properties /Transistor-level realization of AND, OR, NAND, NOR, EXOR, etc. and complex logic gates / Interfacing and Fan-in & Fan-out issues of IC logic circuits /Speed - delay considerations for digital circuits /Power consumption issues of different logic gate realizations