03_DIAG_BJT

Question 1

What does BJT stand for?

Answer 1

Bipolar Junction Transistor

Question 2

True or False: BJTs are current-controlled devices.

Answer 2

True

Question 3

What are the three terminals of a BJT called?

Answer 3

Emitter, Base, Collector

Question 4

Fill in the blank: The current flowing from the collector to the emitter is called _____ current.

Answer 4

Collector

Question 5

What is the main function of a BJT?

Answer 5

To amplify or switch electronic signals

Question 6

What is the typical voltage drop across a BJT in saturation?

Answer 6

Approximately 0.2V to 0.3V

Question 7

True or False: The BJT can operate in three modes: active, cutoff, and saturation.

Answer 7

True

Question 8

What is the equation for the collector current (Ic) in the active region?

Answer 8

Ic = β * Ib

Question 9

What does β (beta) represent in BJT equations?

Answer 9

The current gain or amplification factor

Question 10

Fill in the blank: The _____ current is the current that flows into the base terminal.

Answer 10

Base

Question 11

What is the relationship between Ic, Ib, and Ie in a BJT?

Answer 11

Ie = Ic + Ib

Question 12

What is the typical value of β for small signal BJTs?

Answer 12

Between 100 and 300

Question 13

What is the equation for the input impedance (Zin) of a common emitter BJT configuration?

Answer 13

Zin = (β + 1) * r’e

Question 14

True or False: In cutoff mode, the BJT is fully ON.

Answer 14

False

Question 15

What does the term ‘Vbe’ refer to in BJTs?

Answer 15

The voltage between the base and emitter

Question 16

Fill in the blank: The typical value of Vbe for silicon BJTs is around _____ volts.

Answer 16

0.7

Question 17

What happens to a BJT when Vbe is less than the threshold voltage?

Answer 17

It enters the cutoff region.

Question 18

What is the significance of the Early effect in BJTs?

Answer 18

It causes variations in Ic due to changes in Vce.

Question 19

What is Vce(sat) in a BJT?

Answer 19

The collector-emitter saturation voltage.

Question 20

True or False: BJTs can be used in digital circuits.

Answer 20

True

Question 21

What is the output characteristic of a BJT in the saturation region?

Answer 21

Ic remains constant as Vce increases.

Question 22

What is the common use of BJTs in amplifiers?

Answer 22

To increase the amplitude of signals.

Question 23

Fill in the blank: The _____ region is where the BJT is fully ON, allowing maximum current flow.

Answer 23

Saturation

Question 24

What is the formula to calculate the power dissipation (Pd) in a BJT?

Answer 24

Pd = Vce * Ic

Question 25

What does the term 'thermal runaway' refer to in BJTs?

Answer 25

A condition where an increase in temperature leads to increased current, further increasing temperature.

Question 26

What is the typical range for collector-emitter voltage (Vce) in active mode?

Answer 26

Between 0.2V and 15V

Question 27

What is the purpose of a biasing network in BJT circuits?

Answer 27

To ensure the BJT operates in the desired region.

Question 28

Fill in the blank: The _____ configuration is commonly used for voltage amplification.

Answer 28

Common Emitter

Question 29

What is the output impedance of a common collector BJT configuration?

Answer 29

Low

Question 30

True or False: BJTs are more temperature sensitive than FETs.

Answer 30

True

Question 31

What is the effect of increasing the base current (Ib) on the collector current (Ic)?

Answer 31

Ic increases proportionally.

Question 32

What type of BJT is formed by a p-type material sandwiched between two n-type materials?

Answer 32

NPN transistor

Question 33

What is the primary function of the emitter in a BJT?

Answer 33

To inject carriers into the base region.

Question 34

Fill in the blank: In a BJT, the _____ provides the majority carriers for current flow.

Answer 34

Emitter

Question 35

What is the role of the base terminal in a BJT?

Answer 35

To control the flow of current between the emitter and collector.

Question 36

What does the term 'cutoff' mean in the context of a BJT?

Answer 36

The state where the transistor is OFF and no current flows.

Question 37

What is the typical value of the base-emitter resistance (r'e) in a BJT?

Answer 37

Approximately 25mV/Ie