Explain CMOS Inverter with the help of a neat circuit diagram.

Ans:

CMOS Inverter:

The fundamental CMOS logic circuit is an inverter demonstrated in Fig.(a). For above circuit the logic levels are as 0 V (logic 0) and VCC (logic 1). While V_i = V_cc, T₁ turns ON and T₂ turns OFF. So VO ≈ 0 V and as the transistors are connected in series, the current ID is extremely small. Conversely, when V_i = 0 V, T₁ turns OFF and T₂ turns ON providing an output voltage VO ≈ Vcc and ID is again extremely small. Into either logic state, T₁ or T₂ is OFF and the quiescent power dissipation that is the product of the OFF leakage current and Vcc is extremely low. Extra complex functions can be realized through combinations of inverters.

Fig.(a) Logic Diagram of CMOS Inverter