CMOS TECHNOLOGY

--> CMOS (COMPLEMENTARY METAL OXIDE SEMICONDUCTOR) uses both pmos and nmos transistor.

--> Transistor CMOS are formed by two complementary networks.

--> Pull up network is the complement pull down network.

--> It is a parallel to series and series to parallel connections.

 MOS TRANSISTOR:

--> It have four terminals.
   1.SOURCE
   2. GATE
   3..DRAIN
   4. BODY(bulk=substrate)

NMOS OPERATION:

--> Body is normally tied to ground.

--> When gate is low voltage:
             1. P-type body is at low voltage.
             2. Source-body and drain-body diodes are off
             3. No current flows, transistor is off.

PMOS OPERATION:

--> Similar, but doping and voltage reversed
           1. Body tied to high voltage.

           2. Gate low: transistor ON
           3. Gate high: transistorOFF
           4. Bubble indicates inverted behavior.

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