Reference no: EM13529155

1. When an AC signal is supplied to a CE amplifier, the input signal moves the operating point _____.
a. along the DC load line
b. along the AC load line
c. between the AC and DC load lines
d. nowhere

2. What is a common application of CB amplifiers?
a. Buffer
b. RF amplifier
c. Oscillator
d. Switching circuit with hysteresis

3. Comparing the AC parameters of the CB and CE amplifiers, the main difference is that the CB amplifier has ________.
a. very low input resistance
b. higher voltage gain
c. higher output resistance
d. input and output signals that differ in phase by 180 degrees

4. Which of the following is true for a common-base amplifier?


a. The input signal is applied to the base.
b. The output signal is taken from the base.
c. The base is not connected.
d. The base is the reference terminal for the input and output signal.

5. Which of the following is not a common amplifier?
a. BJT
b. CE
c. CC
d. CB

6. What are the three terminals of an FET?
a. Gate, emitter, source
b. Gate, drain, collector
c. Gate, drain, source
d. Gate, drain, base

7. For an n-channel JFET, when VGS becomes more negative, the ___________.
a. channel becomes more narrow
b. channel becomes wider
c. channel width is unchanged
d. drain current reverses direction

8. When looking at a JFET drain characteristic curve, the constant-current region __________.
a. is in between the pinch-off voltage and the start of the breakdown region
b. is in between 0 volts and the pinch-off voltage
c. can only exist when VGS = VGS(off)
d. can only be found on the transconductance curve

9. Why must the gate-to-source voltage of an n-channel JFET always be either zero or negative?
a. To forward bias the gate source junction

b. To reverse bias the gate source junction
c. To allow for saturation
d. To correctly provide negative bias to the amplifier
10. A specific p-channel JFET has a VGS(OFF) = +6 V. What is the ID when VGS = +8 V?
a. VGS
b. VCC
c. Zero
d. 6 V

11. What type of transistor is normally off when the gate-to-source voltage is 0 V?
a. JFET
b. D-MOSFET
c. E-MOSFET
d. N-MOSFET

12. What type of transistor is represented in the following figure?

a. P-Channel E-MOSFET
b. N-Channel E-MOSFET
c. P-Channel D-MOSFET
d. N-Channel D-MOSFET

13. Which type of MOSFET can be operated with either positive or negative VGS?
a. E-MOSFET
b. D-MOSFET
c. P-MOSFET
d. N-MOSFET


14. Which MOSFET biasing circuit is the preferred method for biasing a D-MOSFET because of its simplicity and effectiveness?
a. Zero-bias
b. Voltage divider
c. Source bias
d. Current-source bias

15. What is the preferred D-MOSFET biasing method?
a. Hold gate-to-source at AC input levels.
b. VGS = 0.
c. Apply source voltage to gate.
d. Drain-to-source voltage is zero.

16. In normal operation, the gate to source resistance of a JFET is _______ the base to the emitter resistance of a BJT.
a. the reciprocal of
b. higher than
c. lower than
d. equal to

17. For a common source amplifier, the phase relationship between VOUT and VIN is ________.
a. 0
b. 45
c. 90
d. 180

18. Which of the following are the attributes of an ideal FET analog switch?
a. When closed, it has no resistance to the signal; when open, it has infinite resistance.
b. None of the listed options are correct.
c. When closed, it has infinite resistance; when open, it has no resistance to the signal.

d. When closed, it is in cut-off mode; when open, it is in saturation mode.

19. Explain why a MOSFET power switch is less susceptible to thermal runaway than a BJT power switch.
a. MOSFETs have a negative temperature coefficient; BJTs have a positive temperature coefficient.
b. MOSFETs have a positive temperature coefficient; BJTs have a negative temperature coefficient.
c. BJTs run hotter than MOSFETs.
d. MOSFETs have better heat syncs than BJTs.

20. How is crossover distortion in Class B amplifiers avoided?
a. Operate with the Q-point on the center of the AC load line.
b. Use the push-pull configuration.
c. Adjust the biasing to overcome the VBE of the transistors.
d. Use FETs instead of BJTs.

21. The efficiency of an amplifier is the ratio of the ________.
a. power supplied to the load to the power delivered by the DC supply
b. output power to input power
c. output impedance to input impedance
d. stage 2 voltage gain to stage 1 voltage gain

22. What is used to provide bias and gain stability in direct-coupled amplifiers?
a. Bypass capacitors
b. Transformer coupling
c. Negative feedback
d. Base biasing

23. What is the maximum theoretical efficiency of a Class A amplifier?
a. 50%
b. 100%

c. 15%
d. 25%

24. The purpose of the capacitor between the two stages of a capacitively coupled amplifier is to ________.
a. develop the DC collector voltage in the first stage
b. couple the AC signal and block the DC voltage
c. decrease the gain of the first stage
d. provide negative feedback for the second stage

25. RG180B/U is a coaxial cable with a nominal impedance of 95 Ω and a capacitance per foot of 15.5 pF/ foot. Determine the inductance per foot of this cable.
a. 250 nH/ft
b. 45 nH/ft
c. 140 nH/ft
d. 95 nH/ft

26. What is the nucleus of an atom made of?
a. Electrons
b. Protons
c. Neutrons
d. Protons and neutrons

27. What are the particles in the outermost shell called?
a. Valence electrons
b. Valence protons
c. Ions
d. Energy

28. The sharing of electrons produces ______________ that hold atoms together.
a. conduction bands
b. valence shells
c. covalent bonding
d. semiconductors

29. What is the most common semiconductor material in use today?
a. Diode
b. Transistor
c. Varactor
d. Silicon

30. When electrons create vacancies in the valence band, what is this known as?
a. A hole
b. Doping
c. Recombination
d. Intrinsic


31. What does forward biasing mean?
a. A condition that permits current across a pn junction
b. Placing a negative meter lead on the anode
c. The identifier on the diode that denotes the cathode
d. A condition that permits increase in resistance across a pn junction

32. Reverse bias is achieved by _________________.
a. preventing current across the pn junction
b. supplying the negative side of the source to the p region
c. making the anode more negative than the cathode
d. connecting a battery to the two ends of a diode

33. What is the maximum reverse-biased voltage that a diode can withstand called?
a. Reverse breakdown voltage
b. Avalanche voltage
c. Peak inverse voltage (PIV)
d. Depletion voltage

34. What does a rectifier circuit do?
a. Rectifies audio signals for amplification
b. Rectifies DC voltage to pure AC sine waves
c. Converts AC into pulsating DC
d. Uses 0.7 V to overcome distortion

35. What output voltage value does a 7805 IC regulator chip provide?
a. -5 V
b. +5 V
c. -12 V
d. +12 V


36. What type of diode works in the reverse direction and is used as a voltage regulator?
a. Varactor
b. Regulator
c. LM317
d. Zener

37. The ripple voltage of a full-wave bridge with a capacitive filter is ________.
a. less than the VRIP of a half-wave rectified power supply with the same capacitive filter
b. equal to the VP of the transformers secondary voltage
c. at the same frequency as the input frequency
d. not dependent on the value of the load resistor

38. What type of waveform is produced from a bridge rectifier circuit with an open diode?
a. Full-wave output equal to Vsec - 1.4
b. Full-wave output equal to Vsec - 0.7
c. Half-wave output equal to Vsec - 1.4
d. Half-wave output equal to Vsec - 0.7

39. To maintain a constant voltage supplied to the load, we can use ________.
a. a Zener diode
b. an IC regulator
c. a high-resistance voltage divider
d. either a Zener diode or an IC regulator

40. Refer to the following figure. The circuit is a ________.



a. positive clamper
b. positive limiter with positive bias
c. negative clamper
d. negative limiter with negative bias

41. Which of the following is not a region within the BJT device?
a. Emitter
b. Collector
c. Cathode
d. Base

42. In both the npn and pnp transistors, correct biasing is considered to be:
a. BC junction reverse biased and BE forward biased
b. BC junction forward biased and BE reverse biased
c. Positive voltage being applied to the collector of a pnp transistor
d. Negative voltage being applied to the collector of an npn transistor

43. What is Kirchhoff's Law for a transistor regarding current?
a. IE = IC + IB
b. IC = IE + IB
c. IB = IC + IE
d. IB = IC.IE


44. How much voltage drop does the forward-biased base-emitter junction require?
a. -0.7 V
b. +0.3 V
c. -0.3 V
d. +0.7 V

45. For silicon NPN bipolar junction transistors, ________.
a. IC = IB + IE
b. IDC = IE/IC
c. IC is the largest current
d. VB = VE + 0.7 V

46. DC beta refers to the ratio of the _______ current to ___________ current.
a. collector; base
b. base; collector
c. emitter; collector
d. collector; emitter

47. When using a bipolar junction transistor as a switch that is closed, IC is ________.
a. equal to IB
b. in saturation
c. in cutoff
d. in midrange

48. A switch in the open position has __________.
a. VCE = 0
b. VCE = VCC
c. VCE = IC(sat) RC
d. VCE = VBE

49. The metal case of a power transistor package is common to the ________.

a. emitter
b. collector
c. base
d. amplifier

50. In a common collector amplifier, AV equals ________.
a. 1
b. RE / r'e
c. RLOAD / ZIN
d. ZIN / ZOUT