Field Effect Transistors (Fet) MCQs

Practice and Learn through MCQs and Quizzes. W3Definitions.com have 33 Field Effect Transistors (Fet) MCQs

A __________ change in VDS will produce a __________ change in ID.

  • A. small, large
  • B. large, small
  • C. large, large
  • D. small, small
  • Correct Answer: Option B

A _______________ JFET amplifier provides a voltage gain of less than one.

  • A. common-source
  • B. common-gate
  • C. common-drain
  • D. cascode amplifier
  • Correct Answer: Option C

A “U” shaped, opposite-polarity material built near a JFET-channel center is called the:

  • A. gate
  • B. block
  • C. drain
  • D. heat sink
  • Correct Answer: Option A

A MOSFET has how many terminals?

  • A. 2 or 3
  • B. 3
  • C. 4
  • D. 3 or 4
  • Correct Answer: Option D

A very simple bias for a D-MOSFET is called:

  • A. self biasing
  • B. gate biasing
  • C. zero biasing
  • D. voltage-divider biasing
  • Correct Answer: Option C

D-MOSFETs are sometimes used in series to construct a cascode high-frequency amplifier to overcome the loss of:

  • A. low output impedance
  • B. capacitive reactance
  • C. high input impedance
  • D. inductive reactance
  • Correct Answer: Option C

How will electrons flow through a p-channel JFET?

  • A. from source to drain
  • B. from source to gate
  • C. from drain to gate
  • D. from drain to source
  • Correct Answer: Option D

IDSS can be defined as:

  • A. the minimum possible drain current
  • B. the maximum possible current with VGS held at –4 V
  • C. the maximum possible current with VGS held at 0 V
  • D. the maximum drain current with the source shorted
  • Correct Answer: Option C

In an n-channel JFET, what will happen at the pinch-off voltage?

  • A. the value of VDS at which further increases in VDS will cause no further increase in ID
  • B. the value of VGS at which further decreases in VGS will cause no further increases in ID
  • C. the value of VDG at which further decreases in VDG will cause no further increases in ID
  • D. the value of VDS at which further increases in VGS will cause no further increases in ID
  • Correct Answer: Option A

In the constant-current region, how will the IDS change in an n-channel JFET?

  • A. As VGS decreases ID decreases.
  • B. As VGS increases ID increases.
  • C. As VGS decreases ID remains constant.
  • D. As VGS increases ID remains constant.
  • Correct Answer: Option A

JFET terminal “legs” are connections to the drain, the gate, and the:

  • A. channel
  • B. source
  • C. substrate
  • D. cathode
  • Correct Answer: Option B

Junction Field Effect Transistors (JFET) contain how many diodes?

  • A. 4
  • B. 3
  • C. 2
  • D. 1
  • Correct Answer: Option C

One advantage of voltage-divider bias is that the dependency of drain current, ID, on the range of Q points is _________.

  • A. reduced
  • B. increased
  • C. not affected
  • D. none of the above
  • Correct Answer: Option A

The common-source JFET amplifier has:

  • A. a very high input impedance and a relatively low voltage gain
  • B. a high input impedance and a very high voltage gain
  • C. a high input impedance and a voltage gain less than 1
  • D. no voltage gain
  • Correct Answer: Option A

The overall input capacitance of a dual-gate D-MOSFET is lower because the devices are usually connected:

  • A. in parallel
  • B. with separate insulation
  • C. with separate inputs
  • D. in series
  • Correct Answer: Option D

The transconductance curve of a JFET is a graph of:

  • A. IS versus VDS
  • B. IC versus VCE
  • C. ID versus VGS
  • D. ID × RDS
  • Correct Answer: Option C

The type of bias most often used with E-MOSFET circuits is:

  • A. constant current
  • B. drain-feedback
  • C. voltage-divider
  • D. zero biasing
  • Correct Answer: Option B

To get a negative gate-source voltage in a self-biased JFET circuit, you must use a ________.

  • A. negative gate supply voltage
  • B. ground
  • C. voltage divider
  • D. source resistor
  • Correct Answer: Option D

What is the input impedance of a common-gate configured JFET?

  • A. very low
  • B. low
  • C. high
  • D. very high
  • Correct Answer: Option A

When an input delta of 2 V produces a transconductance of 1.5 mS, what is the drain current delta?

  • A. 666 mA
  • B. 3 mA
  • C. 0.75 mA
  • D. 0.5 mA
  • Correct Answer: Option B

When an input signal reduces the channel size, the process is called:

  • A. enhancement
  • B. substrate connecting
  • C. gate charge
  • D. depletion
  • Correct Answer: Option D

When applied input voltage varies the resistance of a channel, the result is called:

  • A. saturization
  • B. polarization
  • C. cutoff
  • D. field effect
  • Correct Answer: Option D

When is a vertical channel E-MOSFET used?

  • A. for high frequencies
  • B. for high voltages
  • C. for high currents
  • D. for high resistances
  • Correct Answer: Option C

When not in use, MOSFET pins are kept at the same potential through the use of:

  • A. shipping foil
  • B. nonconductive foam
  • C. conductive foam
  • D. a wrist strap
  • Correct Answer: Option C

When testing an n-channel D-MOSFET, resistance G to D = , resistance G to S = , resistance D to SS = and 500 , depending on the polarity of the ohmmeter, and resistance D to S = 500 . What is wrong?

  • A. short D to S
  • B. open G to D
  • C. open D to SS
  • D. nothing
  • Correct Answer: Option D

When the JFET is no longer able to control the current, this point is called the:

  • A. breakdown region
  • B. depletion region
  • C. saturation point
  • D. pinch-off region
  • Correct Answer: Option A

When VGS = 0 V, a JFET is:

  • A. saturated
  • B. an analog device
  • C. an open switch
  • D. cut off
  • Correct Answer: Option A

Which component is considered to be an “OFF” device?

  • A. transistor
  • B. JFET
  • C. D-MOSFET
  • D. E-MOSFET
  • Correct Answer: Option D

Which JFET configuration would connect a high-resistance signal source to a low-resistance load?

  • A. source follower
  • B. common-source
  • C. common-drain
  • D. common-gate
  • Correct Answer: Option A

Which type of JFET bias requires a negative supply voltage?

  • A. feedback
  • B. source
  • C. gate
  • D. voltage divider
  • Correct Answer: Option C

With a 30-volt VDD, and an 8-kilohm drain resistor, what is the E-MOSFET Q point voltage, with ID = 3 mA?

  • A. 6 V
  • B. 10 V
  • C. 24 V
  • D. 30 V
  • Correct Answer: Option A

With a JFET, a ratio of output current change against an input voltage change is called:

  • A. transconductance
  • B. siemens
  • C. resistivity
  • D. gain
  • Correct Answer: Option A

With the E-MOSFET, when gate input voltage is zero, drain current is:

  • A. at saturation
  • B. zero
  • C. IDSS
  • D. widening the channel
  • Correct Answer: Option B