Analog Electronics - Practice Test

[#351] In a practical oscillator circuit, which one of the following limits the amplitude of the oscillations?

(A) Onset of non-linearity

(B) Power supply voltage

(C) Oscillation frequencies

(D) Temperature of the active device

Correct Answer

(A) Onset of non-linearity

[#352] Quartz crystal is mostly used in crystal oscillator because

(A) It is easily available

(B) It has superior electrical properties

(C) It is quite inexpensive

(D) It is very rugged

Correct Answer

(B) It has superior electrical properties

[#353] A microphone is connected between the base and the ground of a BJT. A 1 kΩ resistance is connected between the collector V CC . If I s = 6 × 10 -16 A and the peak value of the microphone signal is 20 mV, what is the peak value of the output signal?

(A) 1.29 × 10 -16 V

(B) 1.29 × 10 -6 V

(C) 1.29 × 10 -12 V

(D) 1.29 × 10 -14 V

Correct Answer

(C) 1.29 × 10 -12 V

[#354] Consider the oscillator circuit shown in the figure. The function of the network (shown in dotted lines) consisting of the 100 kΩ resistor in series with the two diodes connected back-to-back is to:

(A) Introduce amplitude stabilization by preventing the op-amp from saturating and thus producing sinusoidal oscillations of fixed amplitude

(B) Introduce amplitude stabilization by forcing the op-amp to swing between positive and negative saturation and thus producing square wave oscillations of fixed amplitude

(C) Introduce frequency stabilization by forcing the circuit to oscillate at a single frequency

(D) Enable the loop gain to take on a value that produces square wave oscillations

Correct Answer

(A) Introduce amplitude stabilization by preventing the op-amp from saturating and thus producing sinusoidal oscillations of fixed amplitude

[#355] Reverse saturation current in the collector region of a transistor

(A) Increases with temperature

(B) Decreases with temperature

(C) Is not affected by temperature

(D) Is affected by base current

Correct Answer

(A) Increases with temperature

Analog Electronics - Study Mode

[#351] In a practical oscillator circuit, which one of the following limits the amplitude of the oscillations?

Correct Answer

[#352] Quartz crystal is mostly used in crystal oscillator because

Correct Answer

[#353] A microphone is connected between the base and the ground of a BJT. A 1 kΩ resistance is connected between the collector V CC . If I s = 6 × 10 -16 A and the peak value of the microphone signal is 20 mV, what is the peak value of the output signal?

Correct Answer

[#354] Consider the oscillator circuit shown in the figure. The function of the network (shown in dotted lines) consisting of the 100 kΩ resistor in series with the two diodes connected back-to-back is to:

Correct Answer

[#355] Reverse saturation current in the collector region of a transistor

Correct Answer