Transistor Biasing Question & AnswersJuly 6, 2021 By WatElectronics This article lists 100 Transistor Biasing MCQs for engineering students. All the Transistor Biasing Questions & Answers given below includes solution and link wherever possible to the relevant topic.Transistor's most common application is to perform amplification as the time-varying signals applied at the input terminals get amplified based on the external DC voltages applied. To achieve amplification, the transistor's input junction must be forward-biased and the junction at the output must be reversely biased. Faithful amplification's purpose is to achieve the signals with an increase in magnitude and without altering the shape of the signal.The process of applying external voltages at the junctions of the transistor is known as bias. This biasing makes the transistors operate in the required region. 1). The weaker signals are applied at the ________ of the transistor to amplify it. Collector Base Emitter All the above HintWeaker signals are applied across the base as input2). External __________ voltages are applied to bias a transistor. AC DC Both AC or DC Analog HintExternal DC voltages are applied3). What are the conditions to achieve Faithful amplification? VBE must be at minimum VCE must be at minimum Zero signal current at the collector a, b and c HintBase-emitter junction must be forward-biased4). The flow of proper zero signal collector currents and the maintenance of the proper voltages at collector-emitter during the flow of signals is known as ________. Transistor biasing Transistor at cut-off Transistor at saturation Unbiased transistor HintBiased circuit5). N-P-N transistor made of silicon with Vcc = 8V and the collector at load Rc = 1.4-kilo-ohms. Find the maximum of the current at the collector required to achieve amplification? 3 mA 4 mA 5 mA 6 m A HintTo achieve faithful amplification VCE for the transistor made of silicon must not be less than 1 Volts6). Inherent variations in the parameters of transistors can change _______________. Operating point Biasing Amplification Filteration HintUnfaithful amplification7). Operating point of a transistor must be independent of _____________. Biasing Amplification Variations in parameters Filteration HintOperating point to maintain8). What does operating point projects? Values of VBE and Ic Signal’s magnitude VCE and Ic values of zero signals Signal’s frequency HintIc and the VCE values of the zero signals9). The current at the collector changes in a rapid manner due to ___________. Temperature changes Inherent changes of parameters Both a and b Resistor connected HintChange in parameters and the temperature10). Amplifier circuit without biasing leads to _______. Decreasing base current Faithful amplification Unfaithful amplification Proper functioning HintExternal supply must be provided11). A circuit provided with transistor biasing is known as ______. Biased circuit Bias battery Bias diode Resistive circuit HintFaithful amplification12). The process to make the operating point independent of changes in temperature and other variations are known as ______. Biasing Stabilisation Modulation Rectification HintStabilization of operating point13). VBE for the silicon made transistor must be not lesser than __________ volts. Zero 0.01 0.7 0.1 HintSilicon-made transistor14). To operate the transistor properly the collector must be ______. Forward bias Reverse bias Neither forward nor reverse Either forward or reverse HintReversely biased for amplification15). VCE for the transistor must not be less than __________ to obtain faithful amplification. Zero V 0.01 V 0.7 V 1 V HintVoltage at the collector-emitter junction should not be lesser than 1 v16). What is the necessity for stabilization? Temperature dependence Individual variations Thermal runaway a, b and c HintChanges in temperature and the other inherent variations17). Which type of bias provides stabilization? Base-resistor bias Collector-feedback bias Potential-divider bias Emitter-feedback bias HintPotential-divider bias uses the external resistors18). __________ are used to carry the excess heat. Resistors Heat sink Both a and b Transistors HintBase-emitter temperature19). Self-destruction of the transistor is termed as _____________. Stabilization Biasing Thermal Runaway Amplification HintUnstabilized transistors undergo self-destruction20). To maintain stability factor __________ must be constant. Ic β IB Both b and c Hint β and IB both are maintained constant21). The intersection point of DC and AC load line is referred to as __________. Operating point Biasing Amplification Transition HintOperating point should be maintained constant22). Operating point is also known as_______. Saturation point Quiescent point Cut-off point Zero point HintQ-point23). What are the methods to bias a transistor? Potential-divider bias Collector-feedback bias Base-resistor bias a, b and c HintTransistor biasing for the BJTs24). For a N-P-N transistor a resistor must be connected between base and ___________. Positive end of the supply Negative end of the supply Collector Emitter HintBase and the positive end of the supply of the N-P-N transistor25). For a P-N-P transistor a resistor must be connected between base and ___________. Positive end of the supply Negative end of the supply Collector Emitter HintN-P-N and P-N-P transistors is the supply polarity at the inputTransistor Biasing MCQs for Exams26). What is the ideal value of the stability factor? 100 200 1 0 HintStability factor will be zero27). Stability factor of the Base-resistor method is _________. β+1 2 (β+1) β (β+1) 3 (β+1) HintStability factor is large28). Where will be the biasing point present to make the transistor to function as an amplifier? Cut-off Active Saturation Both a and c HintTransistor works as an amplifier in the active region29). The operating point can be shifted anywhere in the active region in ________ method. Potential-divider bias Collector-feedback bias Base-resistor bias Emitter-feedback bias HintBy changing the RB value operating point can be placed anywhere30). What can be the disadvantage of Base-resistor method? Complicated to design Sensitive to the changes in β High stability Multiple components needed HintChange in β31). Operating point is __________ in the Fixed bias. Stable Linear Unstable Can’t say HintOperating point unstable32). Fixed bias is used in __________. Linear circuits Transistor as current source Switching Both a and b HintPoor stabilization33). Stability factor is high in ___________. Potential-divider bias Collector-feedback bias Base-resistor bias Emitter-feedback bias HintThermal runaway34). The fixed bias circuit can be modified by attaching another resistor externally at _____________ terminal of the transistor. Collector Emitter Base Anode Hint Emitter feedback bias uses negative feedback35). The change in parameter β leads to change in __________ in fixed bias method. Zero signal current at emitter Zero signal current at base Zero signal current at collector Zero signal current at Cathode HintChange in parameters and the current at the terminal collector36). Q-point in the base bias method is dependent on ____________. β Collector current Emitter current Resistor HintThe operating point is dependent upon β37). Two sources of DC are used in ___________ bias circuit. Collector Emitter Base Both a and c HintEmitter bias circuit in which one is negative and the other is positive38). Zero signal current at the collector is _________ m Amps during the initial stage of transistor. 4 3 2 1 HintIc must be maintained at unity39). The change in temperature makes the Q-point to shift because of _________. Change in ICBO Change in Vcc Change in resistance values of the circuit Change in β HintICBO lead to the change in Q-point40). One end of the resistor connected to the base and the other is connected to the collector in _________ feedback bias method. Collector Emitter Base Both a and c HintCollector-feedback biasing method41). Negative feedback in the collector-feedback bias reduces _________ of amplifier. Stability Current Voltage Gain HintGain reduction because of feedback42). What is the most popular method of biasing? Potential-divider bias Collector-feedback bias Base-resistor bias Data insufficient HintStability is concerned voltage-divider biasing43). Stability in Voltage-divider is achieved due to ___________. RE in series with the emitter RE in series with the collector RE in series with the base RC in series with the emitter HintRE connected in series with the terminal emitter44). The cause for thermal runaway is ________. Forward biased Emitter Reverse biased Collector High capacitance at junction Unbiased transistor HintNo external Dc supplied to the transistor45). In the voltage-divider circuit drop at the resistor R2 _________ the Base-Emitter junction. Forward biases Reverse biases Neither forward nor reverse Both a and b HintJunction Base-emitter forward biased46). What is the disadvantage of Voltage-divider bias method? Lower base current Multiple resistors Stability factor is high Can’t say HintMultiple resistors are needed in the Potential –divider method47). What are the advantages of Voltage-division biasing method? Single supply of DC Q-point independent of β Q-point stabilized for Temperature shifts a, b and c HintIndependence on various inherent parameters48). Which biasing method is used in Linear circuits? Potential-divider bias Collector-feedback bias Base-resistor bias Emitter-feedback bias HintPotential-divider bias due to its merits and highly stabilization49). Q-point lying on the center of the DC load line of the amplifier circuit, these amplifiers are said to be __________. Fixed biased Collector biased Midpoint biased Base biased HintIc and VCE offers ‘one-half’ of their possible maximum values50). _____________ amplifiers produce optimum outcomes. Fixed biased Collector biased Midpoint biased Base biased HintLarge possible outputs can be producedTransistor Biasing Important MCQs51). ________ is used to compensate the voltages and currents and maintain operating point stable. Fixed biased Collector biased Midpoint biased Bias compensation HintBias compensation makes use of devices sensitive to temperature52) . What are the devices used for bias compensation? Diode Thermistor Transistor a, b, and c HintDiodes, Thermistors, and transistors are devices sensitive to temperature53). Collector-base bias and the voltage-divider bias uses _________ feedback. Positive Negative Zero Neither positive nor negative HintReduce the amplification of the signals54). In the diode compensation method diode is connected at ____________ circuit. Collector Emitter Base Resistor HintThe diode-connected at the base must possess the same characteristic of the transistor55). Voltage-divider bias method is also known as __________. Fixed bias Collector bias Midpoint bias Self bias HintSelf-bias requires more components56). The change in VBE can be compensated by the changing the voltage across the diode in ________ method Diode compensation Transistor compensation Thermistor compensation Resistor compensation HintTransistor and the diode characteristics must be the same57). For compensating ICO saturation current at diode must be equal to ___________. Transistor saturation current Transistor Leakage current Voltage across the diode Voltage across the transistor HintEquivalent to the leakage current at the transistor58). Ic = β IB is possible in _____________ method. VBE diode compensation Transistor compensation Thermistor compensation Ico diode compensation HintIc = β IB59). ___________ method requires fewer components. Fixed bias Collector bias Midpoint bias Self bias HintFixed bias offers flexibility60). Stability factor is dependent upon RB and RE in _______ method. Fixed bias Collector bias Midpoint bias Self bias HintGreat stability is provided by the self-biasing method61). ICBO gets doubled for every __________ degree C temperature rise. 10 20 30 40 HintFor every 10 degrees Celsius temperature rise ICBO tends to double62). The rate of change in current at the collector to the Ico change is known as _____. Operating point Saturation factor Active factor Stabilization factor HintIB and β are maintained constant to stabilize the collector63). Stability factor should be _______ to achieve stability. Small Medium Large Maximum HintSmall stability factor64). The resistance in thermistor ____________ with ___________ in the temperature. Decreases, Increase Decreases, Decrease Increases, Increase Increases, Decrease HintTemperature in the biased circuit increases the Thermistor resistance decreases65). Decrease in the resistance decreases VBE leads to decrease in ___________. IB Ic ICBO None of the above HintDecrease in the base current66). The resistance in sensistor ___________ with __ in the temperature. Decreases, Increase Decreases, Decrease Increases, Increase Increases, Decrease HintThe temperature in the sensistor compensated circuit increases67). In the Sensitor biasing compensation increase in the resistance leads to decrease in _______. IB VR2 IC Both b and c HintDecreases the emitter forward bias68). Thermal runaway can be avoided by ______. Shifting the operating point Unbiasing a transistor Stabilizing the Operating point Both a and b HintOperating point independent of temperature and the other parameters69). The transistor made up of silicon the rise in ICBO is for every ________________ degree C. 10 12 14 16 HintSilicon it rises for 12 degrees Celsius70). What are the advantages of using Silicon over Germanium? Smaller ICBO Working temperature PIV rating is high All the above HintSilicon-made devices don't get damaged easily71). What is disadvantage of silicon made devices? Smaller ICBO Working temperature PIV rating is high Potential barrier HintHigher biasing voltage is required by the silicon-made devices72). The germanium-made transistor operates at 25 degrees C. With ICBO 5 micro Amps, Zero signal Ic= 2 milli Amps and β = 40. Calculate the cut-off current at the collector? 0.105 mA 0.205 mA 0.305 mA 0.405 mA Hint ICEO = (β+1) ICBO73). The absence of resistor at the junction of base-emitter offers ___________ on the source in a fixed bias of base circuit. Load Resistance No load Both a and b HintThe absence of the resistor leads to no loading74). Automatic control in gain can be achieved using _________ bias method. Fixed base bias Collector bias Midpoint bias Self bias HintThe base-resistor method is used in switching75). In the collector bias method the base and the collector voltages are _____________. Dependent Independent Proportional Can’t say HintVB = VC - IBRBTransistor Biasing MCQs for Quiz76). Collector bias method is also known as _____________ feedback. Self-bias Self-biasing with Negative Self-biasing with Positive None of the above HintSelf-biasing circuit with Negative feedback77). The reduction of current at base to decrease the current at the ____________ in collector bias. Base Emitter Collector Junction HintThe reduced current at the terminal collector78). The improvisation of collector biasing method is __________. Fixed base bias Collector bias Midpoint bias Dual feedback bias HintConnecting an additional resistor to the collector79). _________ biases the junction of Base-Emitter in the emitter bias. VEE VBB VCC VBE HintBase-emitter junction forward biased80). _________ biases the junction of Collector-base in the emitter bias. VEE VBB VCC VBE HintCollector-base reversely biased81). Self-emitter bias has _______ and _____feedbacks. Collector-base Emitter Collector-Emitter Both and b HintEmitter and the Collector-base feedbacks are employed82). Output gain is reduced in Self-emitter bias is due to ________ feedback. Positive Negative Degenerative Regenerative HintUnwanted feedback of AC leads to a reduction in the gain83). The gain reduced in self-bias emitter can be compensated using __________. Inductor Resistor Diode By-pass capacitor HintBy-pass capacitor to overcome the gain reduced84). In voltage-divider biasing the voltage at R2 is considered as the _______ voltage. Base Emitter Collector Junction HintBase voltage of the transistor85). The value of IC can be restored to original by decreasing ___________. Base current Emitter current Collector current Junction current HintDecreasing the base currents86). BJTs can be biased using ________________. Active networks Passive networks Silicon or Zener diodes Both a and c HintActive networks as well as Zener and the silicon diodes87). Transistor can be operated linearly due to __________. Biasing Inductor Diode By-pass capacitor HintBiasing makes the transistor88). Straight line drawn about the output characteristics of transistor is known as _________. AC load line DC load line Load line None of the above HintLoad line89). AC signal applied to the transistor_______ and _______ tends to vary. Voltage, Current Power, Voltage Current, Power Resistance, Voltage HintAC signal is applied Current and the Voltage tends to vary90). Load line drawn when both the external voltages of DC and the input signals are applied is known as ____________-. AC load line DC load line Load line None of the above HintLoad line of AC91). How can you differentiate between AC and DC load lines? Only external DC applied Only input signal applied Both External DC voltage and input signal applied None of the above HintApplied signals of the input and the external DC applied92). At _____________ the current and the voltage parameters of both sections match. Active point Saturation point Biasing point Point of concurrence HintThe intersecting point of the AC and DC load lineRead More About Transistor Biasing93). Due to collector is reversely biased the transistor offers high ___________. Input impedance Output impedance Input Capacitance Junction capacitance HintImpedance at the output is high94).For a transistor to function as amplifier the DC load is _________than that of AC load. Same as Lesser More Can’t say HintDC load must be higher than that of AC load95). To establish the operating point correctly __________ is needed. Selection of proper biasing resistors Proper Load resistors selection Appropriate current at input All the above HintSelecting the proper load and the bias resistors and providing appropriate currents and voltages96). Automatic biasing and the feedback by resistors is provided in ________ method. Fixed base bias Collector bias Midpoint bias Dual feedback bias HintDual feedback biasing mechanism offers automatic feedback97). __________feedback can be used for Low Power supply Voltages. Fixed base Collector Emitter Dual feedback HintEmitter feedback circuit can be used in Low Power supply Voltages98). Distortion free output of amplifier is produced by ________. Proper biasing Operating point operate in active region Operating point operate in saturation region Both a and b HintProperly biasing to make the transistor operate in the active region99). Transistor biased circuit must be ____________. Simple Easy to implement Cost-effective All the above HintCost-effective and simple to understand and implement100). What is the difference between Sensistor and Thermistor bias compensation? Negative temperature coefficient Positive temperature coefficient Both a and b Operating point HintSensistor has a positive coefficient of temperature Time is Up! Time's up
