Diode Characteristics: Master the Fundamentals of Diode Behavior

Question 1

Which of the following best describes the forward bias characteristics of a diode?

Accepted Answer

Forward current increases exponentially with increasing forward voltage.

Answer

Forward voltage decreases linearly with increasing forward current.

Answer

Forward resistance remains constant.

Answer

Forward breakdown voltage is typically higher than reverse breakdown voltage.

Question 2

When a diode is forward biased, what happens to the concentration of majority carriers in the n-type region?

Accepted Answer

It increases.

Answer

It decreases.

Answer

It stays the same.

Answer

It becomes zero.

Question 3

Which of the following does NOT affect the breakdown voltage of a diode?

Accepted Answer

Forward bias current

Answer

Doping concentration

Answer

Junction area

Answer

Temperature

Question 4

In a reverse-biased diode, the depletion region:

Accepted Answer

Expands and the electric field increases

Answer

Shrinks and the electric field decreases

Answer

Expands and the electric field decreases

Answer

Shrinks and the electric field increases

Question 5

The dynamic resistance of a diode in forward bias is:

Accepted Answer

Very low

Answer

Very high

Answer

Infinite

Answer

Zero

Question 6

Which of the following is an application of a zener diode?

Accepted Answer

Voltage regulation

Answer

Signal rectification

Answer

Current limiting

Answer

Amplification

Question 7

The turn-on voltage of a diode is:

Accepted Answer

The voltage at which significant current starts to flow

Answer

The voltage at which the diode becomes reverse-biased

Answer

The voltage at which the diode reaches its maximum current

Answer

The voltage at which the diode breaks down

Question 8

In a half-wave rectifier circuit, the capacitor is used to:

Accepted Answer

Store energy and smooth the output voltage

Answer

Block the AC component of the input voltage

Answer

Limit the current through the diode

Answer

Amplify the output voltage

Question 9

In a diode operating in forward bias, what happens to the depletion region?

Accepted Answer

Decreases in width

Answer

Increases in width

Answer

Remains unchanged

Answer

Oscillates rapidly

Question 10

Which factor does NOT influence the reverse saturation current of a diode?

Accepted Answer

Surface recombination

Answer

Temperature

Answer

Doping concentration

Answer

Junction area

Question 11

Which type of diode emits light when forward biased?

Accepted Answer

Light-emitting diode (LED)

Answer

Zener diode

Answer

Schottky diode

Answer

Varactor diode

Question 12

In forward bias, the dynamic resistance of a diode:

Accepted Answer

Is much lower than the reverse resistance

Answer

Is equal to the reverse resistance

Answer

Is much higher than the reverse resistance

Answer

Is negative

Question 13

Which characteristic best describes the I-V curve of a diode?

Accepted Answer

Sharp knee

Answer

Linear relationship

Answer

Symmetry around the origin

Answer

Constant value throughout the bias range

Question 14

Voltage regulation is a common application for:

Accepted Answer

Zener diode

Answer

Amplification

Answer

Rectification

Answer

Frequency modulation

Question 15

When a diode is reverse-biased, what happens to the depletion region?

Accepted Answer

Expands

Answer

Shrinks

Answer

Stays the same

Answer

Disappears

Question 16

Which statement accurately describes the behavior of an ideal diode under forward bias?

Accepted Answer

Low resistance and high current

Answer

High resistance and low current

Answer

High resistance and high current

Answer

Low resistance and low current

Question 17

In reverse bias, what is the primary mechanism leading to the breakdown of a diode?

Accepted Answer

Both Avalanche multiplication and Zener breakdown

Answer

Tunneling

Answer

Avalanche multiplication

Answer

Zener breakdown

Question 18

In voltage regulation circuits, what is the main role of a diode?

Accepted Answer

Voltage regulation

Answer

AC voltage rectification

Answer

Overvoltage protection

Answer

Signal amplification

Question 19

Which diode type exhibits a sharp reverse breakdown voltage and can serve as a voltage reference?

Accepted Answer

Zener diode

Answer

Schottky diode

Answer

Tunnel diode

Answer

PIN diode

Question 20

How does increasing the temperature typically affect the reverse saturation current of a diode?

Accepted Answer

Increases

Answer

Decreases

Answer

Remains constant

Answer

Becomes zero

Question 21

In what application are tunnel diodes commonly utilized?

Accepted Answer

Radio frequency oscillators

Answer

Power rectification

Answer

Voltage regulation

Answer

Light-emitting diodes

Question 22

What is the primary purpose of incorporating a shunt resistor in a diode circuit?

Accepted Answer

Overcurrent protection for the diode

Answer

Voltage regulation

Answer

High-frequency response improvement

Answer

Reverse leakage current reduction

Question 23

Which statement correctly describes the dynamic resistance of a diode?

Accepted Answer

It equals the slope of the I-V curve

Answer

It is constant

Answer

It is independent of operating point

Answer

It is zero

Question 24

What is the main advantage of employing a PIN diode instead of a standard diode?

Accepted Answer

Faster switching speed

Answer

Lower forward voltage drop

Answer

Higher reverse breakdown voltage

Answer

Enhanced temperature stability

Question 25

The voltage drop across a forward-biased silicon diode at room temperature is approximately:

Accepted Answer

0.7 V

Answer

2.0 V

Answer

1.0 V

Answer

0.3 V

Question 26

When a reverse-biased diode enters breakdown, the primary mechanism responsible for high current flow is:

Accepted Answer

Avalanche breakdown

Answer

Surface breakdown

Answer

Zener breakdown

Answer

Punch-through

Question 27

Which of the following factors does NOT significantly influence the reverse saturation current of a diode?

Accepted Answer

Forward bias voltage

Answer

Temperature

Answer

Doping concentration

Answer

Reverse bias voltage

Question 28

Which application exploits the exponential I-V characteristic of diodes?

Accepted Answer

Logarithmic amplifier

Answer

Voltage regulator

Answer

Rectifier

Answer

Clipper

Question 29

The primary function of a diode in a rectifier circuit is to:

Accepted Answer

Allow current flow in one direction only

Answer

Filter out noise

Answer

Amplify the signal

Answer

Protect the circuit from overvoltage

Question 30

Which type of diode is characterized by a sharp reverse breakdown and precise voltage regulation?

Accepted Answer

Zener diode

Answer

Schottky diode

Answer

Power diode

Answer

Light-emitting diode (LED)

Question 31

The depletion region in a diode serves the primary purpose of:

Accepted Answer

Preventing current flow under reverse bias

Answer

Providing a low-resistance path for current

Answer

Storing charge carriers

Answer

Enhancing current flow under forward bias

Question 32

What is the typical forward-bias threshold voltage of a silicon diode at room temperature?

Accepted Answer

Approximately 0.7 V

Answer

Approximately 2.1 V

Answer

Approximately 1.4 V

Answer

Approximately 0.3 V

Question 33

Which region of a diode's I-V curve exhibits a constant voltage drop?

Accepted Answer

Forward-bias saturation region

Answer

Reverse-bias ohmic region

Answer

Reverse-bias breakdown region

Answer

Forward-bias ohmic region

Question 34

What is the primary function of a Zener diode?

Accepted Answer

Voltage regulation

Answer

Current amplification

Answer

Frequency multiplication

Answer

Signal rectification

Question 35

Which type of diode typically exhibits the lowest forward-bias resistance?

Accepted Answer

Schottky diode

Answer

Tunnel diode

Answer

P-N junction diode

Answer

PIN diode

Question 36

What is a key advantage of using an ideal diode model?

Accepted Answer

Simplified circuit analysis

Answer

Precise results under all bias conditions

Answer

Accurate prediction of non-linear behavior

Answer

Inclusion of temperature effects

Question 37

A diode is connected to a voltage source with the positive terminal connected to the n-type side. In this condition, the diode is said to be:

Accepted Answer

Forward biased

Answer

Reverse biased

Answer

Capacitively biased

Answer

Unbiased

Question 38

The current-voltage (I-V) characteristic of an ideal diode in the forward bias region is characterized by:

Accepted Answer

Low resistance

Answer

Zero voltage drop

Answer

High resistance

Question 39

The reverse saturation current of a diode is the current that flows through the diode when:

Accepted Answer

It is reverse biased with no external voltage applied

Answer

It is reverse biased with a large voltage applied

Answer

It is forward biased with a small voltage applied

Answer

It is forward biased with no external voltage applied

Question 40

The breakdown voltage of a diode is the voltage at which:

Accepted Answer

Reverse current increases rapidly

Answer

Forward current increases rapidly

Answer

Diode resistance decreases rapidly

Question 41

The temperature dependence of a diode's forward voltage drop is such that it:

Accepted Answer

Decreases with increasing temperature

Answer

Increases with increasing temperature

Answer

Varies randomly with changing temperature

Answer

Remains constant with changing temperature

Question 42

The primary function of a Zener diode is to:

Accepted Answer

Regulate voltage

Answer

Detect light

Answer

Amplify current

Answer

Store charge

Question 43

A characteristic of a Schottky diode is its:

Accepted Answer

Low forward voltage drop

Answer

Long recovery time

Answer

High reverse current

Answer

High capacitance

Question 44

A photodiode is a diode that:

Accepted Answer

Converts light into an electrical current

Answer

Converts an electrical current into light

Answer

Stores charge

Answer

Regulates voltage

Question 45

Which of the following factors affects the reverse saturation current of a diode?

Accepted Answer

Temperature

Answer

Capacitance

Answer

Frequency

Answer

Voltage

Question 46

In a forward-biased diode, which of the following occurs to the depletion region?

Accepted Answer

Narrows

Answer

Widens

Answer

Shifts towards the p-side

Answer

Becomes non-existent

Question 47

What is the typical forward voltage drop for a silicon diode?

Accepted Answer

0.7 V

Answer

1.4 V

Answer

2.8 V

Answer

0.3 V

Question 48

The ratio of forward current to reverse current in a diode is referred to as:

Accepted Answer

Rectification ratio

Answer

Forward bias ratio

Answer

Dynamic resistance

Answer

Turn-on ratio

Question 49

In a reverse-biased diode, which carriers are the majority in the respective regions?

Accepted Answer

Holes in the p-region and electrons in the n-region

Answer

Electrons and holes in both regions

Answer

Electrons in the p-region and holes in the n-region

Question 50

Which factor primarily affects the reverse saturation current of a diode?

Accepted Answer

Temperature

Answer

Dynamic resistance

Answer

Reverse voltage

Answer

Forward voltage

Question 51

The dynamic resistance of a diode is defined as:

Accepted Answer

The slope of the I-V curve in the forward bias region

Answer

The slope of the I-V curve in the reverse bias region

Answer

The ratio of forward current to forward voltage

Question 52

Which application primarily utilizes the forward bias characteristics of a diode?

Accepted Answer

Light-emitting diode (LED)

Answer

Capacitance multiplier

Answer

Zener diode voltage regulator

Answer

RF mixer