m2 - chap 4 Flashcards
Which of the following currents is nearly equal to each other?
A) IB and IC
B) IE and IC
C) IB and IE
D) IB, IC, and IE
B) IE and IC
The ratio of which two currents is represented by B?
A) IC and IE
B) IC and IB
C) IE and IB
D) None of the above
B) IC and IB
At what region of operation is the base-emitter junction forward biased and the base-collector junction reverse biased?
A) Saturation
B) Linear or active
C) Cutoff
D) None of the above
B) Linear or active
Calculate the approximate value of the maximum power rating for the transistor represented by the output characteristics of Figure 4.1?
A) 250 mW
B) 170 mW
C) 50 mW
D) 0 mW
B) 170 mW
The cutoff region is defined by IB _____ 0 A.
A) >
B) <
C) ≤
D) >
C) ≤
The saturation region is defined by VCE _____ VCEsat
A) >
B) <
C) ≤
D) >
C) ≤
For the BJT to operate in the active (linear) region, the base-emitter junction must be ______-biased and the base-collector junction must be _______-biased.
A) forward, forward
B) forward, reverse
C) reverse, reverse
D) reverse, forward
B) forward, reverse
For the BJT to operate in the saturation region, the base-emitter junction must be _____-biased and the base-collector junction must be _______-biased.
A) forward, forward
B) forward, reverse
C) reverse, reverse
D) reverse, forward
A) forward, forward
Which of the following voltages must have a negative level (value) in any npn bias circuit?
A) VBE
B) VCE
C) VBC
D) None of the above
C) VBC
For what value of ẞ does the transistor enter the saturation region?
A) 20
B) 50
C) 75
D) 116
D) 116
Determine the reading on the meter when VCC = 20 V, RC = 5 kΩ, and IC = 2 mA.
A) 10 V
B) -10 V
C) 0.7 V
D) 20 V
A) 10 V
Which of the following is assumed in the approximate analysis of a voltage divider circuit?
A) IB is essentially zero amperes.
B) R1 and R2 are considered to be series elements.
C) BRE > 10R2
D) All of the above
D) All of the above
It is desirable to design a bias circuit that is independent of the transistor beta.
A) True
B) False
A) True
- Calculate the voltage across the 91 kΩ resistor.
A) 18 V
B) 9.22 V
C) 3.23 V
D) None of the above
C) 3.23 V
Calculate the value of VCEQ.
A) 8.78 V
B) 0 V
C) 7.86 V
D) 18 V
C) 7.86 V
Calculate ICsat
A) 35.29 MA
B) 5.45 MA
C) 1.86 mA
D) 4.72 mA
D) 4.72 mA
Calculate VCE. (VEE = 9 V)
A) 4.52 V
B) -4.52 V
C) 4.48 V
D) -4.48 V
B) -4.52 V
Calculate VCE. (VEE = -9 V)
A) -4.52 V
B) 4.52 V
C) -9 V
D) 9 V
B) 4.52 V
Which of the following is (are) related to an emitter-follower configuration?
A) The input and output signals are in phase.
B) The voltage gain is slightly less than 1.
C) Output is drawn from the emitter terminal.
D) All of the above
D) All of the above
Determine the values of VCB and IB for this circuit.
A) 1.4 V. 59.7 μA
B) -1.4 V. 59.7 μA
C) -9.3 V. 3.58 μA
D) 9.3 V. 3.58 μА
A) 1.4 V. 59.7 μA
Calculate ETh for this network.
A) -12.12 V
B) 16.35 V
C) -3.65 V
D) 10
C) -3.65 V
Calculate Rsat if VCE = 0.3 V.
Α) 49.2 Ω
Β) 49.2 ΚΩ
C) 49.2 mΩ
D) 49.2 MΩ
Α) 49.2 Ω
You can select the values for the emitter and collector resistors from the information that is provided for this circuit.
A) True
B) False
B) False
In the case of this circuit, you must assume that VE = 0.1VCC in order to calculate RC and RE.
A) True
B) False
A) True
Which of the following is (are) the application(s) of a transistor?
A) Amplification of signal
B) Switching and control
C) Computer logic circuitry
D) All of the above
D) All of the above
Calculate the storage time in a transistor switching network if toff is 56 ns, tf = 14 ns, and tr = 20 ns.
A) 70 ns
B) 42 ns
C) 36 ns
D) 34 ns
B) 42 ns
The total time required for the transistor to switch from the “off” to the “on” state is designated as ton and defined as the delay time plus the time element.
A) True
B) False
A) True
For an “on” transistor, the voltage VBE should be in the neighborhood of 0.7 V.
A) True
B) False
A) True
For the typical transistor amplifier in the active region, VCE is usually about ____% to ____% of VCC.
A) 10, 60
B) 25, 75
C) 40, 90
B) 25, 75
- Which of the following is (are) a stability factor?
A) S(ICO)
B) S(VBE)
C) S(B)
D) All of the above
D) All of the above
In a fixed-bias circuit, which one of the stability factors overrides the other factors?
A) S(ICO)
B) S(VBE)
C) S(B)
D) Undefined
C) S(B)
In a voltage-divider circuit, which one of the stability factors has the least effect on the device at very high temperature?
A) S(ICO)
B) S(VBE)
C) S(B)
D) Undefined
C) S(B)
Use this table to determine the change in IC from 25°C to 175°C for RB/RE= 250 due to the Sico) stability factor. Assume an emitter-bias configuration.
A) 140.34 nA
B) 140.34 μA
C) 42.53 nA
D) 0.14034 nA
B) 140.34 μA
Determine the change in IC from 25°C to 175°C for the transistor defined in this table for fixed-bias with RB = 240 kn and B = 100 due to the S(VBE) stability factor.
A) 145.8 μA
B) 145.8 nA
C) -145.8 μA
D) -145.8 nA
A) 145.8 μA
Determine ICQ at a temperature of 175°C if ICQ = 2 mA at 25°C for RB/RE = 20 due to the S(B) stability factor.
A) 2.417 mA
B) 2.392 mA
C) 2.25 mA
D) 2.58 mA
A) 2.417 mA
By definition, quiescent means
A) quiet
B) still
C) inactive
D) All of the above
D) All of the above
________ should be considered in the analysis or design of any electronic amplifiers.
A) dc
B) ac
C) dc and ac
D) None of the above
C) dc and ac
For the dc analysis the network can be isolated from the indicated ac levels by replacing the capacitor with
A) an open circuit equivalent
B) a short circuit equivalent
C) a source voltage
D) None of the above
A) an open circuit equivalent
In a fixed-bias circuit with a fixed supply voltage VCC’ the selection of a level of a ______ resistor sets the ______ current for the operating point.
A) collector, base
B) base, base
C) collector, collector
D) None of the above
B) base, base
Changes in temperature will affect the level of
A) current gain B
B) leakage current ICEO
C) both current gain ẞ and leakage current ICEO
D) None of the above
C) both current gain ẞ and leakage current ICEO
In a fixed-bias circuit, the magnitude of IC is controlled by and therefore is a function of
A) RB
B) RC
C) B
D) RB and B
D) RB and B
For a transistor operating in the saturation region, the collector current IC is at its ________ and the collector-emitter voltage VCE is to the ___________
A) minimum, left of the VCEsat line
B) minimum, right of the VCEsat line
C) maximum, left of the VCEsat line
D) maximum, right of the VCEsat line
C) maximum, left of the VCEsat line
The dc load line is determined solely by the
A) base-emitter loop
B) collector-emitter loop
C) base-collector loop
D) None of the above
B) collector-emitter loop
A change in value of ______ will create a new load line parallel to its previous one in a fixed-bias circuit.
A) RB
B) RC
C) VCC
D) VBE
C) VCC
In a fixed-bias circuit, the slope of the dc load line is controlled by
A) RB
B) RC
C) VCC
D) IB
B) RC
The emitter resistor in an emitter-stabilized bias circuit appears to be _________ in the base circuit.
A) larger
B) smaller
C) the same
D) None of the above
A) larger
___________ is the primary difference between the exact and approximate techniques used in the analysis of a voltage divider circuit.
A) Thevenin voltage ETh
B) Thevenin resistance RTh
C) Base voltage VB
D) RC
B) Thevenin resistance RTh
The Thevenin equivalent network is used in the analysis of the _____ circuit.
A) fixed bias
B) emitter-stabilized bias
C) voltage divider
D) voltage feedback
C) voltage divider
The saturation current of a transistor used in a fixed-bias circuit is _________ its value used in an emitter-stabilized or voltage-divider bias circuit for the same values of RC’
A) more than
B) the same as
C) less than
D) None of the above
A) more than
In a collector feedback bias circuit, the current through the collector resistor is ______ and the collector current is ________
A) IC’ IC
B) IB + IC’ IC
C) IB, IC
D) None of the above
B) IB + IC’ IC
_____ is the least stabilized circuit.
A) Fixed bias
B) Emitter-stabilized bias
C) Voltage divider
D) Voltage feedback
A) Fixed bias
_____ is less dependent on the transistor beta.
A) Fixed bias
B) Emitter bias
C) Voltage divider
D) Voltage feedback
C) Voltage divider
In a transistor-switching network, the level of the resistance between the collector and emitter is _______ at the saturation and is ________ at the cutoff.
A) low, low
B) low, high
C) high, high
D) high, low
B) low, high
In a transistor-switching network, the operating point switches from ________ to _________ regions along the load line.
A) cutoff, active
B) cutoff, saturation
C) active, saturation
D) None of the above
B) cutoff, saturation
For the typical transistor amplifier in the active region, VCE is usually about _____ % to _____% of VCC’
A) 0,100
B) 25,75
C) 45,55
D) None of the above
B) 25,75
In any amplifier employing a transistor, the collector current IC is sensitive to
A) B
B) VBE
C) ICO
D) All of the above
D) All of the above
As the temperature increases. B ____, VBE ______, and ICO ______ in value for every 10°C.
A) increases, decreases, doubles
B) decreases, increases, remains the same
C) decreases, increases, doubles
D) increases, increases, triples
A) increases, decreases, doubles
A significant increase in leakage current due to increase in temperature creates _________ between IB curves.
A) smaller spacing
B) larger spacing
C) the same space as at lower temperature
D) None of the above
B) larger spacing
The ___________the stability factor, the _____ sensitive the network is to variations in that parameter.
A) higher, more
B) higher, less
C) lower, more
D) None of the above
A) higher, more
In an emitter-bias configuration, the _________ the resistance RE, the ___________ the stability factor, and the _______ stable is the system.
A) smaller, lower, less
B) larger, more, more
C) smaller, more, more
D) larger, lower, more
D) larger, lower, more
