CHAPTER 8 FIELD –EFFECT TRANSISTORS

CHAPTER 8
FIELD –EFFECT TRANSISTORS

1. FETs are preferred device in low-voltage switching applications; while______ transistor is generally used in high-voltage switching applications.
IGBT

2. What type of JFET operates with a reverse-biased pn junction to control current in the channel?
JFET

3. An n-channel universal transfer characteristic curve is also known as
Transconductance curve

4. The change in drain current for a given change in gate-to-source voltage with the drain-to-source voltage constant
Forward transconductance

5. What is the most common type of JFET bias?
Self-bias
6. It is a method for increasing the Q-point stability of a self-biased JFET by making the drain current essentially independent of gate-to-source voltage
Current-source bias

7. What JFET bias uses a BJT as a constant-current source?
Current-source bias

8. For increased Q-point stability, the value of RS in the self-bias circuit is increased and connected to a negative supply voltage. This sometimes called
Dual-supply bias

9. VGS varies quite a bit for JFET self-bias and voltage-divider bias but ID is much more stable with
Voltage-divider bias

10. ____________ is sometimes called depletion/enhancement MOSFET.
D-MOSFET

11. LDMOSFET has a lateral channel structure and is a type of
Enhancement MOSFET

12. It is an example of the conventional E-MOSFET designed to achieve higher power capability
VMOSFET

13. Following are the three ways to bias a MOSFET except
Current-source bias

14. The insulated-gate bipolar transistor combines which two transistors that make it useful in high-voltage and high-current switching applications?
BJT and MOSFET

15. What are the three terminals of IGBT?
Gate, collector, emitter

16. In terms of switching speed, __________ switch fastest and _____________ switch slowest.
MOSFETs, BJTs

17. In a MOSFET, the process of removing or depleting the channel of charge carriers and thus decreasing the channel conductivity
Depletion

18. The ratio of change in drain current to a change in gate-to source voltage in a FET
Transconductance

19. A FET is called a ______________ because of the relationship of the drain current to the square of a term containing gate-to-source voltage
Square-law device
20. Combines features from both the MOSFET and the BJT that make it useful in high-voltage and high-current switching applications.
IGBT

21. Has a lateral channel structure and is a type of enhancement MOSFET designed for power applications.
LDMOSFET

CHAPTER 5  
TRANSISTOR BIAS CIRCUITS

1. What biasing method is common in switching circuits?  
Base bias
 
2. A Base bias in linear region shows that it is  
Directly dependent on dc beta

3. In an emitter-feedback bias, if the collector current increases, the emitter voltage Increases

4. What happens to the base voltage in no. 10?  
Increases
 
5. In an emitter-feedback, the increase in base voltage _________ the base current. Reduces
 
6. For collector-feedback bias, what provides the bias for the base-emitter junction? Collector voltage
 
7. As temperature goes up in a collector-feedback circuit, βDC and VBE goes _______ and __________, respectively.  
Up and down

8. Collector-feedback bias provides good stability using negative feedback from  
Collector to base

9. Innovations in technology would allow a doubling of the number of transistors in a given space every year and that the speed of those transistors would increase. This prediction is widely known as  
Moore’s law

10. If an amplifier is not biased with correct dc voltages on the input and output, it can go ___________ when an input signal is applied.  
Saturation or cutoff

11. Given a voltage-divider biased BJT, determine IC given VCC, R1, R2, RC, and RE which are 10V, 10kohms, 4.7kohms, 1kohm, and 470ohms respectively. Use βDC= 100.  
5.31mA

12. What is the value of VCE in no.20?
2.19 V

13. If an emitter resistor is added to a base bias circuit, what is the value of the emitter current given VCC, RE, RC, and RB as 10V, 1kΩ, 470Ω, and 180kΩ, respectively. Use βDC=100.
3.32mA

14. Calculate for VCE in no. 22
5.12 V

15. If the dc beta in the preceding drops half of its original value, find the percent change in IC.
39.16%

16. What is the percent change in VCE?
27.17%

17. The region along the load line including all points between saturation and cutoff
Linear region

18. A voltage divider for which loading effects can be neglected
Stiff voltage divider

19. The base bias circuit arrangement has poor stability because its Q-point varies widely with
Dc beta

20. The purpose of biasing a circuit is to establish a proper stable ________.
Q-point

21. The process of returning a portion of a circuit’s output back to the input in such a way as to oppose or aid a change in the output
Feedback

CHAPTER 4 BIPOLAR JUNCTION TRANSISTORS

CHAPTER 4
BIPOLAR JUNCTION TRANSISTORS

1. Which is the least of the three transistor currents?
Base

2. The ratio of the dc collector current to the dc base current of the transistor is,
dc beta/dc current gain

3. the ratio of the dc collector current to the dc emitter current
dc alpha

4. Determine the base current given dc beta=100 , dc alpha=0.85, and IC= 3.70mA
0.037mA

5. Nonconducting state of a transistor
Cutoff

6. State of a BJT in which the collector current has reached maximum and is dependent of the base current Saturation

7. Neither the base-emitter nor the base-collector junctions are forward-biased
cutoff

8. dc beta varies with
collector current and temperature

9. hFE varies with which transistor current/s?
Collector only

10. Converts light energy to electrical signal
Phototransistor

11. Devices used to electrically isolate circuits
Optocouplers

12. A key parameter in optocouplers is the CTR. CTR stands for
Current transfer ratio

13. Indication of how efficiently a signal is coupled from input to output
CTR

14. RF transistors are designed to operate at
EHF

15. What transistor category/ies uses plastic or metal packages?
General-purpose transistors

16. To operate as an amplifier, BE junction must be forward-biased and the BC junction must be reverse-biased. This is called
Forward-reverse bias

17. In a phototransistor, what transistor current/s is produced and controlled by light?
Base

18. Two basic package types
Through-hole and surface mount

19. The process of increasing the power, voltage, or current by electronic means.
Amplification