CMOS logic gates are digital electronic circuits built using Complementary Metal-Oxide-Semiconductor (CMOS) technology. They use two types of MOSFET transistors, NMOS and PMOS, to perform Boolean logic operations such as NOT, NAND and NOR. CMOS technology is widely used in modern digital integrated circuits because it offers low static power consumption, high input impedance and good noise immunity. 1. How CMOS Logic Gates Work CMOS Logic Gates: Block Diagram CMOS logic gates use complementary PMOS and NMOS transistors to implement digital logic functions. CMOS logic gate block diagram Input A, B, ... CMOS Network PMOS pull-up NMOS pull-down Output Y Examples: NOT, NAND, NOR CMOS circuits use complementary NMOS and PMOS transistors to control the output voltage. In a typical CMOS logic gate, the PMOS network provides a path from the ou...

  Q. Consider the Friis’ transmission equation 𝑃𝑅=(𝑃𝑇𝐺𝑇𝐺𝑅𝜆2) (4𝜋𝐷)2 ⁄ , where P𝑅 and 𝑃𝑇 are the received and the transmitted powers, respectively. G𝑇 and 𝐺𝑅 are the gain of transmitting and receiving antennas, respectively, 𝐷 is the distance between the transmitting and receiving antennas, and 𝜆 is the wavelength in free space. Given: 𝐺𝑇=𝐺𝑅=1.0,𝜆=0.30 m and PT = +10 dBm. Choose the distance (D), in km, from the following options at which the received power, PR = −90 dBm? Solution Given, P T ​ = + 10 dBm P R = − 90   dBm P R ​ = − 90 dBm G T = G R = 1 G T ​ = G R ​ = 1 (linear gain) λ = 0.30   m λ = 0.30 m P R ​ (in dBm) − P T ​   (in dBm):  Power difference in dB dB = 10^(dB/10) (in ratio) Pr = Pt.Gt.Gr.λ^2 / (4.π.D)^2 Or, Pr/Pt = Gt.Gr.λ^2 / (4.π.D)^2 Or, 10^(-90-10)/10 = Gt.Gr.λ^2 / (4.π.D)^2 Or, 10^-10 = 1.1.(0.3)^2 / (4.π.D)^2 Or, D = 15/2π Answer: Option B

  Q. In the circuit shown in the Figure, A and B are logic inputs and Y is the logic output. Which of the following logic operations is realized by the circuit? (A) NOR (B) OR (C) XOR (D) AND  Step 1: Identify the transistors Your diagram has 4 transistors. 2 PMOS The two transistors at the top, connected to V D D V_{DD} . 2 NMOS The two transistors at the bottom, connected to ground. Step 2: Remember the ON/OFF rule This is the most important part! Input at gate PMOS NMOS 0 (LOW) ON OFF 1 (HIGH) OFF ON So, PMOS works opposite to NMOS. Step 3: Understand the connections The two PMOS transistors are in series . Current can flow from V D D V_{DD} to Y Y only when both PMOS are ON . The two NMOS transistors are in parallel . The output can connect to ground if at least one NMOS is ON . Step 4: Check all input combinations Case 1: A = 0, B = 0 Both PMOS are ON. Both NMOS are OFF. ...