Transistors and Applications MCQs : This section focuses on the "Transistors and Applications". These Multiple Choice Questions (MCQs) should be practiced to improve the Transistors and Applications skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Which of the following conditions are needed to properly bias an npn transistor amplifier?
A. Forward bias the base/emitter junction and reverse bias the base/collector junction.
B. Forward bias the collector/base junction and reverse bias the emitter/base junction.
C. Apply a positive voltage on the n-type material and a negative voltage on the p-type material.
D. Apply a large voltage on the base.
A. is a current-controlled device
B. has a low input resistance
C. is a voltage-controlled device
D. is always forward-biased
The primary function of the bias circuit is to
A. hold the circuit stable at VCC
B. hold the circuit stable at vin
C. ensure proper gain is achieved
D. hold the circuit stable at the designed Q-point
The depletion-mode MOSFET
A. can operate with only positive gate voltages
B. can operate with only negative gate voltages
C. cannot operate in the ohmic region
D. can operate with positive as well as negative gate voltages
To get a negative gate-source voltage in a self-biased JFET circuit, you must use a
A. voltage divider
B. source resistor
D. negative gate supply voltage
The formula used to calculate the approximate ac resistance of the base-emitter diode (re) is
B. re 25 mV × IC
Three different points are shown on a dc load line. The upper point represents the
A. minimum current gain
B. quiescent point
C. saturation point
D. cutoff point
In a class B push-pull amplifier, the transistors are biased slightly above cutoff to avoid
A. crossover distortion
B. unusually high efficiency
C. negative feedback
D. a low input impedance
The signal voltage gain of an amplifier, Av, is defined as:
B. Av = IC × RC
In order for feedback oscillators to have any practical value, the gain has to be
A. < 1
The capacitor that produces an ac ground is called a(n)
A. coupling capacitor
B. dc open
C. bypass capacitor
D. ac open
A source follower has a voltage gain (Av) of
A. AV = gmRd
B. AV = gmRS