BEE FREE BEE Bachelor of Electrical Engineering Semiconductor Devices and Circuits Questions and Answers 2

Question 1

What is the primary function of a Zener diode in a circuit?

Accepted Answer

Voltage regulation

Answer

A Zener diode operates in reverse breakdown to maintain a constant voltage across its terminals, making it ideal for voltage regulation.

Question 2

In a MOSFET operating in the saturation region, the drain current is primarily controlled by which parameter?

Accepted Answer

Gate-to-source voltage

Answer

In saturation, the MOSFET drain current depends on the gate-to-source voltage according to the square-law relationship and is nearly independent of drain-to-source voltage.

Question 3

What phenomenon causes the collector current in a BJT to increase slightly with increasing collector-emitter voltage in the active region?

Accepted Answer

Early effect

Answer

The Early effect (base-width modulation) causes the effective base width to narrow as VCE increases, slightly increasing collector current.

Question 4

Which type of semiconductor recombination involves the emission of a photon?

Accepted Answer

Radiative recombination

Answer

Radiative recombination occurs when an electron and hole recombine directly, releasing energy as a photon, which is the basis of LED operation.

Question 5

What is the cutoff frequency of a common-emitter BJT amplifier primarily limited by?

Accepted Answer

Junction capacitances and transit time

Answer

The cutoff frequency is limited by the base-emitter and base-collector junction capacitances combined with carrier transit time through the base.

BEE - Bachelor of Electrical Engineering Practice Test

BEE - Bachelor of Electrical Engineering Practice Test

BEE FREE BEE Bachelor of Electrical Engineering Semiconductor Devices and Circuits Questions and Answers 2