Devry ECET220 final exam 2015

Page 1

Question 1.1. (TCO 1) For the Zener circuit shown below, if Zener Voltage = 12 V, = 15 V, the current flowing through the Zener diode is 50 mA, and R2 = 2 k, determine the value of R1.

Zener Circuit (Points : 5)

53.57 ?

5 k?

10.67 ?

200 ?

Question 2.2. (TCO 2) Which of the following accurately depicts the relationship between the collector, base, and emitter currents in an NPN bipolar junction transistor? (Points : 5)

All of the above

Question 3.3. (TCO 2) What happens when the base current of a transistor is decreased? (Points : 5)

The collector current increases and the emitter current decreases.

The collector current increases and the emitter current increases.

The collector current decreases and the emitter current decreases.

The collector current decreases and the emitter current increases.

Question 4.4. (TCO 2) A transistor has = 100 and = 4 mA A. What is the value for the collector current, ? (Points : 5)

160 mA

360 mA

0.4 A

0.24 A

Question 5.5. (TCO 3) A power amplifier has a gain of 40 dB and an input level of 2 mV. Assuming that the input and output impedances are the same, what is the voltage level at the amplifier output? (Points : 5)

200 mV

300 mV

400 mV

350 mV

Question 6.6. (TCO 4) What is a difference between BJT and FET? (Points : 5)

BJT is a unipolar and current-controlled device, whereas FET is a bipolar and voltage-controlled device.

BJT is a bipolar and voltage-controlled device, whereas FET is a unipolar and current-controlled device.

BJT is a bipolar and current-controlled device, whereas FET is a unipolar and voltage-controlled device.

BJT is a unipolar and voltage-controlled device, whereas FET is a bipolar and current-controlled device.

Question 7.7. (TCOs 2 and 4) In which FET amplifier configuration is the gain less than unity? (Points : 5)

Common-source

Common-gate

Common-drain

Common-base

Question 8.8. (TCO 5) What is the output impedance for an ideal op-amp? (Points : 5)

0

-Rf/Ri

1+Rf/Ri

1000K

Question 9.9. (TCOs 5 and 6) What is the op-amp circuit shown below?

Op-amp Circuit (Points : 10)

Non-inverting amplifier

Differentiator

Summing amplifier

Integrator

Page 2

Page 2

Question 1.1. (TCO 2) For the circuit in the following figure (Figure 3-29, on page 135 in textbook), ? ? ? ? ? ? . Determine the DC base voltage with respect to ground.

Figure 3-29, on page 135 in textbook (Points : 10)

Question 2.2. (TCO 2) For the circuit in the following figure (Figure 3-29, on page 135 in textbook), ? ? ? ? ? ? . Determine the DC current flowing through resistors

Figure 3-29, on page 135 in textbook (Points : 10)

Question 3.3. (TCO 3) For the circuit in the following figure (Figure 3-29, on page 135 in textbook), ? ? ? ? ? ? . Determine the voltage at the DC operating point (Q-point) .

Figure 3-29, on page 135 in textbook (Points : 10)

Question 4.4. (TCO 3) For the circuit in the following figure (Figure 3-29, on page 135 in textbook), ? ? ? ? ? ? . Determine the AC voltage gain.

Figure 3-29, on page 135 in textbook (Points : 10)

Question 5.5. (TCO 3) For the circuit in the following figure (Figure 3-29, on page 135 in textbook), ? ? ? ? ? ? . Notice that the input voltage is at the point between and . Assume . Determine the power gain

Figure 3-29, on page 135 in textbook (Points : 10)

Question 6.6. (TCO 4) For the E-MOSFET Common-Source Amplifier with Voltage-Divider Bias Circuit shown below (Figure 4-41, on page 207 in textbook), ? ? ? ? . Assume ; and . Determine the following.

(1) DC source voltage

(2) DC Drain voltage

(3) The AC output peak-to-peak voltage is input voltage is

Figure 4-41, on page 207 in textbook (Points : 10)

Question 7.7. (TCO 5) For the circuit in the following figure (Figure 6-20, on page 326 in textbook), if ? ? , determine the closed-loop gain.

Figure 6-20, on page 326 in textbook (Points : 10)

Question 8.8. (TCO 5) For the circuit in the following figure (Figure 6-24, on page 328 in textbook), if the closed-loop gain is -50, , determine

Figure 6-24, on page 328 in textbook (Points : 10)

Question 9.9. (TCO 5) For the circuit in the following figure (Figure 8-7, on page 389 in textbook), if ? and ? , and assume and , determine the hysteresis voltage.

Figure 8-7, on page 389 in textbook (Points : 10)

Question 10.10. (TCO 6) For the circuit in the following figure, if ? ? ? , determine the value for so that it will function as an averaging amplifier (meaning the output voltage will be the average value of the input voltages).

(Points : 10)

Question 11.11. (TCO 6) For the circuit in the following figure, if ? ? ? ? , determine the value of output voltage

(Points : 10)

Question 12.12. (TCO 6) For the instrumentation amplifier shown in the following figure (Figure 12-2 on page 549 in textbook), the values for are fixed for a gain of 1 for the differential amplifier. Also, the values of are exactly matched for the same value = R = 30K.

(1) Determine the value of assuming the voltage gain is 500.

(2) If , determine the voltage output

Figure 12-2 on page 549 in textbook (Points : 10)

Question 13.13. (TCO 7) For the low-pass filter shown in the following figure, the frequency response curve is also shown. If ? ? ? , determine the following values.

(1) The critical frequency

(2) The Damping Factor (DF)

(3) The voltage gain and the voltage gain in dB at 0 (DC), 1, 100, and 1000 Hz

Figure 9-9, page 434 in textbook (Points : 10)

Question 14.14. (TCO 7) For the circuit shown below, ? ? , determine the critical frequency. Also, if ? , design the value for to achieve 2nd order Butterworth response.

Figure 9-10, page 435 in textbook (Points : 10)

Question 15.15. (TCO 7) For the circuit shown below, ? ? ? , determine the values of 1) geometric center frequency; 2) the Q factor; and 3) the Bandwidth.

Figure 9-18, page 443 in textbook (Points : 10)

Page 3

Question 1.1. (TCOs 6 and 8) Elaborate on the structure and function of a differentiator constructed by an op-amp circuit. Give an application example. (Points : 15)

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Question 2.2. (TCOs 7 and 8) Elaborate on the difference between the characteristics of the frequency responses of a band-pass filter circuit and a band-stop filter circuit. Give an application example for each type of the filters. (Points : 15)