Deck 13: Mosfets

Question 1

D-MOSFETs can operate in

A) the depletion mode only.
B) the enhancement mode only.
C) the depletion mode and the enhancement mode.

Answer 1

the depletion mode and the enhancement mode.

Question 2

MOSFETs typically have input impedance than JFETs.

A) higher
B) lower
C) similar

Answer 2

higher

Question 3

Groups of digital circuits with nearly identical characteristics are called

A) logic groups.
B) logic families.
C) logic subgroups.
D) logic subfamilies.

Answer 3

logic families.

Question 4

The main drawback to JFET operation is the fact that

A) JFETs have low input impedance.
B) JFETs are restricted to depletion-mode operation.
C) JFETs are restricted to enhancement-mode operation.
D) JFET amplifiers are poor buffers.

Question 5

Which of the following is true for a D-MOSFET that is being operated in the depletion mode?

A) ID > IDSS
B) ID < IDSS
C) ID = IDSS

Question 6

A CMOS inverter has a +10 V supply and an input that varies between 0 V and +10 V. What is the circuit output when the input to the circuit is +10 V?

A) -10 V.
B) 0 V.
C) +10 V.
D) Cannot be determined with the information given.

Question 7

A D-MOSFET has values of IDSS = 10 mA and VGSoff) = -6V. What is the value of ID when VGS = 0 V?

A) 0 mA
B) 5 mA
C) 10 mA
D) Cannot be determined from the information given.

Question 8

When used in an RF amplifier, dual-gate MOSFETs provide for the use of

A) fading.
B) automatic gain control AGC).
C) CMOS logic family.
D) None of the above.

Question 9

The cascode amplifier is used primarily in

A) high frequency applications.
B) digital switching circuits.
C) audio amplifiers.
D) CMOS applications.

Question 10

The dual-gate MOSFET makes a poor cascode amplifier device.

Question 11

CMOS stands for

A) complementary MOS.
B) current MOS.
C) capacitive MOS.
D) conductive MOS.

Question 12

Which of the following biasing circuits can be used with E-MOSFETs?

A) self bias
B) zero bias
C) drain-feedback bias
D) current-source bias

Question 13

bias may be used with D-MOSFETs but not with JFETs.

A) Source
B) Zero
C) Drain-feedback
D) Current-source

Question 14

One advantage that CMOS has over TTL is the fact that

A) CMOS circuits have better power dissipation ratings.
B) CMOS circuits have a lower packing density than TTL.
C) CMOS circuits can be used with positive supply voltages.
D) CMOS circuits are cheaper than TTL circuits.

Question 15

An E-MOSFET has values of VGSth) = 2 V and IDon) = 8 mA @ VGS = 10 V. What is the value of k for the device?

A) 1 × 10-3
B) 1.25 × 10-4
C) 8 × 10-4
D) Cannot be determined with the information given.

Question 16

What type of MOSFETs are designed to be used at high frequencies?

A) VMOS
B) LDMOS
C) E-MOSFETs
D) Dual-gate MOSFETs

Question 17

The E-MOSFET can operate in

A) the depletion mode only.
B) the enhancement mode only.
C) the depletion mode and the enhancement mode.

Question 18

An E-MOSFET has values of VGSth) = 4 V and IDon) = 12 mA @ VGS = 10 V. The device is being used in a circuit that has a value of VGS = 6 V. What is the value of ID for the circuit?

A) 13.33 mA
B) 1 mA
C) 1.33 mA
D) 0 mA

Question 19

Which of the following devices would normally have the highest current-handling capability?

A) E-MOSFETs
B) D-MOSFETs
C) LDMOS
D) Dual-gate MOSFETs

Question 20

The operation of standard MOSFETs is limited at high frequencies because of

A) low maximum values of ID.
B) high maximum values of ID.
C) high gate-to-channel capacitance.
D) low gate-to-channel capacitance.

Question 21

The circuit in Figure is an amplifier.

A) Voltage-divider biased common-emitter
B) Voltage-divider biased common-drain
C) Voltage-divider biased common-source
D) Drain-feedback biased common-source

Question 22

The symbol labeled C is an .

A) E-MOSFET
B) JFET
C) D-MOSFET
D) None of the above.

Question 23

The symbol labeled A is an .

A) E-MOSFET
B) JFET
C) D-MOSFET
D) None of the above.

Question 24

The symbol labeled B is an .

A) E-MOSFET
B) JFET
C) D-MOSFET
D) None of the above.

Question 25

The MOSFET in Figure has the following specifications: IDon) = 10 mA @ VGSon) = 10 V and VGSTh) = 2 V. Determine the value of ID for this circuit.

A) 2.5 mA
B) 3mA
C) 5 mA
D) 10 mA

Question 26

The MOSFET in Figure has the following specifications: IDon) = 10 mA @ VGSon) = 10 V and VGSTh) = 2 V. Determine the value of VDS for this circuit.

A) 2 V
B) 4.5 V
C) 7.5 V
D) 12 V

Question 27

The MOSFET in Figure has the following specifications: IDon) = 10 mA @ VGSon) = 10 V and VGSTh) = 2 V. Determine the value of VGS for this circuit.

A) 2 V
B) 6 V
C) 10V
D) 12 V

Question 28

To protect MOSFETs from static electricity, you should store them in conductive foam.

Question 29

The term packing density refers to:

A) the number of IC chips that can be shipped in one package.
B) the number of circuits or components that can be fabricated in a given amount of space.
C) a particular design method that results in a complex circuit
D) CMOS circuits but not BJT circuits.

Question 30

LDMOS is a special-purpose type of

A) D-MOSFET.
B) E-MOSFET.
C) JFET.
D) BJT.

Question 31

VMOS is a special-purpose type of

A) D-MOSFET.
B) E-MOSFET.
C) JFET.
D) BJT.

Question 32

The MOSFET in Figure has the following specifications: IDon) = 10 mA @ VGSon) = 10 V and VGSTh) = 2 V. Determine the minimum value of k for this circuit.

A) 1.56
B) 1.56 × 10-4
C) 0.001
D) 1.25 × 10-3

Question 33

Many MOSFET devices now contain internal that protect them from static electricity.

A) BJTs
B) zener diodes
C) pn junction diodes
D) capacitors