Pass Transistor Logic

PASS TRANSISTOR LOGIC

The Main Idea:

• Pass-transistor logic utilizes either single NMOS transistors or CMOS transmission gates to implement a network of switches that are controlled by the input logic variables
• - lower total number of transistors than possible w/ CMOS alone
• Since we are utilizing MOSFETs in the series path from input to output to pass or block signal transmission, it is known as pass-transistor logic (PTL)

An essential design requirement...

• - We must ensure that every node has at all times either a low-resistance path to Vdd or ground!

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