# 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

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

• A. common-source
• B. common-gate
• C. common-drain
• D. cascode amplifier

• A. gate
• B. block
• C. drain
• D. heat sink

• A. 2 or 3
• B. 3
• C. 4
• D. 3 or 4

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

• A. self biasing
• B. gate biasing
• C. zero biasing
• D. voltage-divider biasing

## 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

## 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

## 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

## 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

## 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.

• A. channel
• B. source
• C. substrate
• D. cathode

• A. 4
• B. 3
• C. 2
• D. 1

## 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

## 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

## 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

## 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

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

• A. constant current
• B. drain-feedback
• C. voltage-divider
• D. zero biasing

## 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

• A. very low
• B. low
• C. high
• D. very high

• A. 666 mA
• B. 3 mA
• C. 0.75 mA
• D. 0.5 mA

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

• A. enhancement
• B. substrate connecting
• C. gate charge
• D. depletion

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

• A. saturization
• B. polarization
• C. cutoff
• D. field effect

## When is a vertical channel E-MOSFET used?

• A. for high frequencies
• B. for high voltages
• C. for high currents
• D. for high resistances

## 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

## 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

## 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

## When VGS = 0 V, a JFET is:

• A. saturated
• B. an analog device
• C. an open switch
• D. cut off

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

• A. transistor
• B. JFET
• C. D-MOSFET
• D. E-MOSFET

## 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

## Which type of JFET bias requires a negative supply voltage?

• A. feedback
• B. source
• C. gate
• D. voltage divider

• A. 6 V
• B. 10 V
• C. 24 V
• D. 30 V

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

• A. transconductance
• B. siemens
• C. resistivity
• D. gain