Prelim Exam-elecs2 Louie
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Transcript of Prelim Exam-elecs2 Louie
Test - 1 OF 21.) The region that is very thin and lightly doped compared to the collector and emitter region.a. base b. collector c. emitter d. active region2.) The current in BJT consists of both free electrons and holes.a. Unipolar b. Bipolar c. Tripolar d. IE
3.) In cutoff, VCE is a. 0V b. equal to Vcc c. maximum d. b and c
4.) In saturation, VCE is a. 0.7V b. equal to Vcc c. minimum d. maximum5.) To saturate a BJT,a. IB = IC(sat) b. IB > IC(sat)/βDC c. Vcc must be at least 0V d. emitter must be
grounded6.) The bias condition of a transistor to be used as a linear amplifier is calleda. Forward bias b. forward-forward c. reverse-reverse d. collector bias7.) The βDC of a transistor is itsa. current gain b. voltage gain c. power gain d. internal resistance 8.) The emitter current is alwaysa. greater than the base b. less than the collector currentc. greater than the collector current d. answer a and c9.) If IC is 5 times larger than IB, then βDC is a. 0.02 b. 100 c.50 d.50010.) The approximate voltages across the forward-biased base-emitter junction of silicon BJT is a. 0V b.0.7V c.0.3V d.VBB
11.) Once in saturation, a further increase in base current willa. cause the collector current to increase b. not affect the collector currentc. cause collector current to decrease d. turn the transistor off12.) If the base-emitter junction is open, the collector voltage is a. Vcc b.0.V c. floating d.0.2V13.) The largest in the three semiconductor region in BJTa. base b. collector c. emitter d. active region14.) Characterized by a straight-line relationshipa. Gain b. straight line c. parallel d. linear15.) The state of a BJT in which the collector current has reached a maximum and is independent of the base current.a. Cut-off b. Active c. Saturation d. answer a and c16.) Transistor can be operated as an electronic switch ina. Cut-off b. Active c. Saturation d. answer a and c17.) The necessary application of a dc voltage to a transistor or other device to produce a desired mode of operationsa. Amplification c. Bias c. Switching d. Floating
For item 18-20
FIGURE 1
18.) If the transistor in Figure 1 is open from collector to emitter, the voltage across the Rc will a. increase b. decrease c. not change d. will be ≥ 0 19.) If the transistor in Figure 1 is open from collector to emitter, the collector voltage will
a. increase b. decrease c. not change d. will be ≥ 0 20.) If the resistor in Figure 1 is open, the transistor collector voltage will
a. increase b. decrease c. not change d. will be ≥ 0
TEST II:1) If the emitter current of a transistor is 8 mA and the IB is 1/100 of IC, determine the levels of IC and IB.2) Determine the saturation current (ICsat) of the network
3) Using the characteristics of the Figure 3, determine the following for emitter-bias configuration if Q-point is defined at ICQ= 4mA and VCEQ=10Va. Rc if Vcc =24V and RE = 1.2kΩb. Β at the operating pointc. RB
d. Power dissipated by the transistore. Power dissipated by the resistor RC
4) Given the information provided in Figure 4, determine:a. βb. Vccc. RB
5) Given the information appearing in the Figure, solve for the following:a. IC
b. VE
c. VCC
d. VCE
e. VB
f. R1