unit 2

Various measurements are made on an NMOS amplifier for which the drain resistor RD is 20 kΩ. First, DC measurements show the voltage across the drain resistor, VRD, to be 2 V and the gate-to-source bias voltage to be 1.2 V. Then, ac measurements with small signals show the voltage gain to be −10 V/V. What is the value of Vt for this transistor?

• a) 0.7V
  

• b) 0.8V
  

• c) 0.9V
  

• d) 1.0V

Various measurements are made on an NMOS amplifier for which the drain resistor RD is 20 kΩ. First, DC measurements show the voltage across the drain resistor, VRD, to be 2 V and the gate-to-source bias voltage to be 1.2 V. Then, ac measurements with small signals show the voltage gain to be −10 V/V. If the process transconductance parameter is 50μA/V2, what is the MOSFET’s W/L?

• a) 25
  

• b) 50
  

• c) 75
  

• d) 100

Translate this question to English language

• a) 0.08 mA

• b) 0.16 mA

• c) 0.4 mA

• d) 0.8 mA

Which of the following is the fastest switching device?

• a) JEFT
  

• b) Triode
  

• c) MOSFET
  

• d) BJT

Bias point is also referred by the name

• a) DC Operating Point
  

• b) Quiescent Point
  

• c) None of the mentioned

• 
  d) All of the mentioned

What are the various modes of Differential amplifiers?

•  Common or Differential Mode

•  Single Ended

•  Double Ended

   

• All Mentioned Above

What is created if flow of signals has a similar direction?

• Common Mode Interference

   

• Differential Mode Interference

   

• Coherent Interference

•  Non-Coherent Interference

How noise is removed from the Differential amplifier?

• By Rejecting Common Mode Voltages

•  By Accepting Common Mode Voltages

   

• By Rejecting Differential Mode Voltages

•  By Accepting Differential Mode Voltages

Due to a manufacturing error, in the circuit of Fig. 4.19, M2 is twice as wide as M1. Calculate the small-signal gain

if the dc levels of Vin1 and Vin2 are equal.

• 1. = 4 /3* gm1RD

• 2. = 2 /3* gm1RD

• 3. = 1 /3* gm1RD

• 4. = 1 /2* gm1RD

Variable gain control circuit uses __________?

•  Inverting Amplifier

   

• Non-inverting Amplifier

   

• Integrator

   

• Differential Amplifier