Deck 12: Mosfets

Question 1

A simple computer circuit that causes its output voltage to be opposite of the input voltage is the

A) comparator
B) amplifier
C) converter
D) inverter

Answer 1

D

Question 2

Data is a term that refers to numbers,text,graphics,and all other information that can be coded as binary numbers.

Answer 2

True

Question 3

Active-load resistors are necessary with digital ICs because

A) of their small physical size.
B) amplification is require
C) ICs are active devices.
D) passive resistors are too small.

Answer 3

A

Question 4

A device that consists of thousands of microscopically small transistors is

A) a wideband amplifier.
B) a digital gate.
C) an IC.
D) an FET.

Question 5

One of the major advantages of the D-MOSFET is its extremely high input resistance.

Question 6

The main advantage of CMOS is its

A) extremely high voltage gain.
B) low output impedance.
C) low cost.
D) extremely low power consumption.

Question 7

The word digital means continuous,like a sine wave.

Question 8

With zero gate voltage,a JFET is on,whereas an E-MOSFET is off.

Question 9

The minimum gate to source voltage that causes current to flow from source to drain is called the saturation voltage.

Question 10

The E-MOSFET is primarily a switching device.

Question 11

The depletion-mode MOSFET or D-MOSFET is a normally off device.

Question 12

The operation of a depletion-mode MOSFET is similar to that of a JFET when V_GS is negative.

Question 13

In a MOSFET,the gate is metalliC.

Question 14

A discrete E-MOSFET widely used in applications that control motors,lamps,disk drives,and power supplies is called a

A) complementary MOS.
B) power FET.
C) digital FET.
D) analog FET.

Question 15

A signal that is discontinuous and jumps between two distinct voltage levels is called ________.

A) analog
B) digital
C) cosine wave
D) sine wave

Question 16

Depletion-mode MOSFETs can operate with only a positive gate voltage.

Question 17

One method used to reduce the current drain of a digital circuit is with

A) passive resistors.
B) constant current sources.
C) complementary MOS.
D) JFETs.

Question 18

When the gate voltage of the E-MOSFET is well above the threshold voltage,the device switches from cutoff to saturation.

Question 19

A p-channel D-MOSFET consists of a drain-to-source p-channel,along with an n-type substrate.

Question 20

The enhancement-mode MOSFET is normally off when the gate voltage is zero.

Question 21

In the circuit shown in Figure 12-16,if the LED drops 2 V and the input voltage is +4.5 V,what is the drain current?

A) 20 mA
B) 0 mA
C) 18 mA
D) 4.5 mA

Question 22

Which transistor devices are inherently temperature-stable and cannot go into thermal runaway?

A) BJTs
B) small-signal MOSFETs
C) low-power JFETs
D) power FETs

Question 23

When the gate voltage is zero,the E-MOSFET is

A) off.
B) on.
C) in saturation.
D) biased in the active region.

Question 24

A signal that is continuous like a sine wave is referred to as ________.

A) analog
B) digital
C) truncated
D) chopped

Question 25

A circuit that converts an input direct current voltage to an output dc voltage that is either higher or lower is called

A) an inverter.
B) a multiplexer.
C) a dc-to-ac converter.
D) a dc-to-dc converter.

Question 26

Since the conducting channel of a VMOS is much wider along both sides of the V groove

A) the current can be much larger.
B) the current is much smaller.
C) there is much less distortion.
D) the input resistance is much lower.

Question 27

When the gate voltage of an E-MOSFET is well above the threshold voltage

A) the device switches from cutoff to saturation.
B) the device is biased as a linear amplifier.
C) the device will stay at saturation.
D) the device will stay at cutoff.

Question 28

The E-MOSFET's primary application is as

A) a linear amplifier.
B) an oscillator.
C) a regulator.
D) a switching device.

Question 29

Why does only negligible gate current flow,in a depletion-mode MOSFET,even when the gate voltage is positive?

A) resistance of the channel is high
B) source is grounded
C) metallic gate is insulated
D) drain is grounded

Question 30

A system that converts a battery's dc voltage to an ac voltage to drive a computer is called

A) an uninterruptible power supply.
B) an inverter.
C) a multiplexer.
D) a battery charger.

Question 31

Personal computers have proliferated because of what semiconductor device?

A) BJT
B) E-MOSFET
C) JFET
D) depletion-mode MOSFET

Question 32

A power FET that operates as a device B and allows device A to communicate with or control device C is called

A) a connector.
B) an interface.
C) a coupler.
D) a transceiver.

Question 33

In the circuit shown in Figure 12-16 (a),when the input voltage is 0 V,what is the current flowing through the relay contacts and the 15 Ω resistor?

A) 8 mA
B) 8 A
C) 48 mA
D) 0 A

Question 34

Why are some MOSFETs manufactured with built-in zener diodes in parallel with the gate and the source?

A) to regulate output voltages
B) to prevent damage from static charges
C) to rectify ac input
D) to produce filtered dc output

Question 35

Because a bipolar junction transistor has a negative temperature coefficient,it may be damaged by

A) static charges.
B) thermal runaway.
C) improper grounding.
D) improper coupling.

Question 36

When two bipolar junction transistors are connected in parallel,the transistor with the lower V_BE takes more collector current than the others in a condition known as

A) current matching.
B) current draining.
C) current hogging.
D) current flowing.

Question 37

When the input voltage to the circuit shown in Figure 12-16 is 0 V

A) the LED is on.
B) the LED is off.
C) the drain voltage is +20 V.
D) the source voltage is +20 V.

Question 38

The minimum gate to source voltage that creates the n-type inversion layer and causes current to flow from source to drain is called

A) cutoff voltage.
B) pinchoff voltage.
C) inversion voltage.
D) threshold voltage.

Question 39

What is the drain saturation current in the circuit shown in Figure 12-15 (a)?

A) 4.5 mA
B) 45 mA
C) 20 mA
D) 200 mA

Question 40

When the input voltage for the circuit shown in Figure 12-15 is +4.5,what is the output voltage?

A) +20 V
B) +10 V
C) 0 V
D) +4.5 V

Question 41

One major advantage of a power FET over a bipolar junction transistor is

A) that an FET is current controlleD.
B) the lack of thermal runaway.
C) the lower input resistance.
D) it requires a larger heat sink.

Question 42

The circuit shown in Figure 12-22 (a)is

A) a small-signal amplifier.
B) a multiplexer.
C) an inverter.
D) a power amplifier.

Question 43

When a MOSFET is configured with its gate connected to its drain

A) it operates as an active resistance.
B) it will amplify only high frequencies.
C) it will stay at cutoff.
D) it will stay at saturation.

Question 44

In the circuit shown in Figure 12-16 (a),what is the drain current at saturation?

A) 48 mA
B) 4.8 mA
C) 8 mA
D) 8 A

Question 45

The most effective method of testing a MOSFET device is by using

A) a DMM.
B) an ohmmeter.
C) a curve tracer.
D) an oscilloscope.

Question 46

In the circuit shown in Figure 12-22,what is V_out at point A of the input signal?

A) 15 V
B) 7.5 V
C) 30 V
D) 0 V