Chapter 11 - JFETs, MOSFETs, & IGBTs

Question 1

Two of the most common types of FETs include the junction field-effect transistor (JFET) in the metal-oxide semiconductor field effect transistor (MOSFET).

Answer 1

TRUE

Question 2

AC transformers are fully compatible with other semiconductor devices, such as standard bipolar transistors, SCRs, triacs, and ICs.

Answer 2

TRUE

Question 3

A JFET Is a unipolar device, which defers in operation from a bipolar Junction transistor.

Answer 3

TRUE

Question 4

The JFET is considered a current driven device rather than voltage driven device.

Answer 4

FALSE

A JFET a voltage driven device.

Question 5

The size of the depletion region is controlled by the drain source voltage.

Answer 5

FALSE

The size of the depletion region is controlled by the gate to source voltage.

Question 6

The power consumption of a JFET in standby operation is significantly more than that of a bipolar transistor controlling the same function.

Answer 6

FALSE

The power consumption is thousands of times less.

Question 7

A Jay a FET should never be forward biased.

Answer 7

TRUE

Question 8

In a P-channel JFET circuit, the positive swing I’ll be input signal increases the gate bias

Answer 8

TRUE

Question 9

The input signal and I’ll put signal are in phase for the common-gate amplifier.

Answer 9

TRUE

Question 10

In common-drain circuits for N-channel and P-channel FET ‘s, the input resistance is low.

Answer 10

FALSE

Then put resistance is high.

Question 11

JFETs are used in many amplifier configurations because they can amplify a wide range of frequencies and have a high input impedance.

Answer 11

TRUE

Question 12

A common-gate JFET circuit can also step up the input impedance of a bipolar transistor.

Answer 12

FALSE

A common-drain** JFET circuit

Question 13

The JK flip-flop has unique feature of changing its state when a voltage, or high state, is applied to its J & K inputs.

Answer 13

TRUE

Question 14

Polysilicon gates are 3 to 4 times slower than aluminum gates.

Answer 14

FALSE

They are 3 to 4 times faster**

Question 15

The main difference in operation between a JFET and a MOSFET is that voltage is applied between the gate in the P and N regions of the MOSFET structure.

Answer 15

TRUE

Question 16

MOSFETs are available only as P-channel devices.

Answer 16

FALSE

Question 17

The depletion-Enhancement MOSFET has the same capacitive affect as the enhancement MOSFET.

Answer 17

TRUE

Question 18

A MOSFET can be constructed with two gates, such as in a dual-gate MOSFET arrangement.

Answer 18

TRUE

Question 19

Care must be exercise when handling a MOSFET since the gate insulation is very thin.

Answer 19

TRUE

Question 20

Unlike the small signal MOSFET, the power MOSFET as fabricated with a vertical structure.

Answer 20

TRUE

Question 21

The main advantage of power MOSFETs as the higher static drain-to-source ON-state resistance.

Answer 21

FALSE

This is the main Disadvantage

Question 22

The main difference in construction between the power MOSFET and IGBT is the addition of an injection layer in the IGBT.

Answer 22

TRUE

Question 23

The ON/OFF state of an IGBT is determined by the source voltage.

Answer 23

FALSE

Gate voltage

Question 24

The OFF state of the IGBT is a Achieved by increasing the gate voltage so that it is greater than threshold voltage

Answer 24

FALSE

ON-state

Question 25

The safe operating area is defined by the maximum collector-emitter voltage and collector current than an IGBT operation must control to protect it from damage.

Answer 25

TRUE

Question 26

To troubleshoot and IGBT, the source to drain resistance and the collector to gate resistance should be measured.

Answer 26

FALSE The gate to emitter*** resistance and the collector to gate resistance.

Question 27

One disadvantage of an IGBT is that the switching speed is inferior to that of a Power MOSFET.

Answer 27

TRUE

Question 28

In multi stage amplifiers, the signal is coupled, or connected, to several stages of application.

Answer 28

TRUE

Question 29

Transformer coupling is a method of amplifier coupling that uses an amplifier circuit consisting of two bipolar transistors connected by a transformer.

Answer 29

TRUE

Question 30

Smaller and lighter bipolar transistors may be used with the Darlington circuit, since less power is dissipated.

Answer 30

TRUE

Question 31

A ______________ is a three or four terminal device without an injection layer in which output voltage is controlled by an input current.

Answer 31

Field effect transistor (FET)

Question 32

The newest type of FET is the ______________

Answer 32

Insulated gate bipolar transistor (IGBT)

Question 33

The two types of JFETs include the N channel in the ______________ channel.

Answer 33

P

Question 34

JFETs may be used as ______________ amplifiers.

Answer 34

Direct current, audio frequency, radio frequency.

Question 35

The ______________ region is the first portion of the characteristic curve of a JFET where the drain current rises rapidly.

Answer 35

Ohmic

Question 36

JETs can be connected into a common ______________ circuit configuration.

Answer 36

Drain, gate, source.

Question 37

In common- ______________ amplifier circuits using N channel and P channel JFETs, the AC input signal is applied to the source in the gate, with the gate at ground potential.

Answer 37

Gate

Question 38

A ______________ is a circuit that provides gain for a weak signal before the signal goes through the normal stages of amplification.

Answer 38

Preamplifier

Question 39

The main body of the ______________ MOSFET is composed of a highly resistant P type material.

Answer 39

Enhancement

Question 40

______________ | mode is the operation of a MOSFET with a positive gate voltage.

Answer 40

Enhancement

Question 41

The primary characteristic that is most desirable in a solid-state switch is ______________.

Answer 41

Fast switching speed, simple drive requirements, and low conduction loss.

Question 42

The advantage of using power MOSFETs over power bipolar transistors is ______________.

Answer 42

Faster switching, lower switching losses, and wider safe operating area (SOA).

Question 43

A ______________ is a three terminal switching device that combines a FET for control with a bipolar transistor for switching.

Answer 43

Insulated gate bipolar transistor IGBT

Question 44

IGBT operation consist of a ______________ operation.

Answer 44

Blocking, on/off state, and latch up.

Question 45

The types of safe operating areas for IGBT’s are the Forward biased safe operating area, reversed biased safe operating area, and ______________ safe operating area.

Answer 45

Short circuit

Question 46

The main advantage of using an IGBT is ______________.

Answer 46

Low on state voltage drop, small chip size, low driving power.

Question 47

IGBT applications include a adjustable frequency drive and ______________.

Answer 47

Pulse width modulation

Question 48

The basic technique for coupling amplifier stages together and to loads is ______________ coupling.

Answer 48

Capacitive, transformer, and direct.

Question 49

______________ coupling is a method of amplifier coupling in which one transistor is directly connected to the base of a second transistor.

Answer 49

Direct

Question 50

A ______________ circuit is an amplifier circuit in which the admit her of one transistor is connected to the base of a second transistor.

Answer 50

Darlington

Question 51

Field ______________ transistors have been the corner stone of new developments and semiconductor technology.

Answer 51

Effect

Question 52

A ______________ is a simple field effect transistor (FET) with a PN Junction in which output current is controlled by an input voltage.

Answer 52

JFET

Question 53

In JFET operation, ______________ to source Voltage controls the drain current and must always provide a reverse bias voltage.

Answer 53

Gate

Question 54

A JFET ______________ curve shows operating characteristics of a JFET.

Answer 54

Characteristic

Question 55

In a ______________ source amplifier, an AC signal is applied across the gate resistor.

Answer 55

Common

Question 56

The ______________-gate circuit is used in applications were the source of the signal requires a low to high impedance match.

Answer 56

Common

Question 57

A ______________ matching circuit can step down impedance levels and preserve the band with and Linearity of the signals being amplified.

Answer 57

Impedance

Question 58

A ______________ is a three to terminal or four terminal electronic switching device with metal oxide or polysilicon insulating material that can be used for amplification.

Answer 58

MOSFET

Question 59

The ______________ MOSFET is constructed similarly to the enhancement MOSFET.

Answer 59

Depletion

Question 60

______________ mode is the operation of a MOSFET with a negative gate voltage.

Answer 60

Depletion

Question 61

_____________ MOSFETs exhibit the properties of a small signal MOSFETs but are designed to handle higher currents.

Answer 61

Power

Question 62

Power MOSFETs were designed primarily for ______________ applications.

Answer 62

Switching

Question 63

The ______________ area is the current Voltage limit in which a power switching device like an IGBT can be operated without being destroyed.

Answer 63

Safe operating

Question 64

The two types of structures used for IGBT construction are the ______________ structure in the non-punching through (NPT) structure.

Answer 64

Punch through (PT)

Question 65

______________ drives are a significant part of green technology.

Answer 65

Adjustable frequency

Question 66

______________ is a type of adjustable frequency drive that she’s frequency and Voltage control.

Answer 66

Pulse Width Modulation Motor Control (PWP)

Question 67

A ______________ amplifier is an amplifier circuit that allow several stages of application.

Answer 67

Multi stage

Question 68

______________ coupling is the joining of two or more circuit so that power can be transferred from one amplifier Stage to another

Answer 68

Amplifier

Question 69

______________ coupling is a method of amplifier coupling that uses an amplifier circuit consisting of two bipolar transistors connected by a capacitor.

Answer 69

Capacitative

Question 70

______________ coupling is a method of amplifier completing that uses an amplifier circuit consisting of two bipolar transistors connected by transformer.

Answer 70

Transformer