Zener Diode Question & Answers October 11, 2021 By WatElectronics This article lists 100 Zener Diode MCQs for Engineering Students. All the Zener Diode Questions & Answers given below includes solution and link wherever possible to the relevant topic. The Zener diodes are the special diodes that are widely used in voltage regulation. The avalanche breakdown and the Zener breakdown are the two types of breakdowns in the Zener diode. The working of a Zener diode is similar to the PN junction diode in forwarding biased conditions. The avalanche breakdown occurs in lightly doped diodes, in the case of lightly doped diodes when you apply high reverse bias potential the electrons will gain the kinetic energy and they will break the covalent bond and collide with other electrons. The avalanche and Zener breakdowns are the two types of reverse breakdown in the Zener diode. The Zener breakdown occurs in the thin region, in high doping materials whereas the avalanche breakdown occurs in a thick region. The Zener diode is also called the breakdown voltage of a diode or breakdown diode. There are three types of Zener analysis are there they are fixed DC voltage & load resistor, fixed DC voltage & variable load resistor, and variable DC voltage & fixed load resistor. The fixed bias current, fixed bias with emitter resistor, collector to base bias circuit, and potential divider bias circuit are the various biasing circuits. The Zener diodes are used in electronic devices, voltage regulators, used as a voltage reference device, etc and they have very high efficiency, they are smaller in size, and less expensive. 1). Which one of the following breakdowns occurs in the thin region? Avalanche Zener Both a and b None of the above None Hint 2). Which one of the following breakdowns occurs in high doping material? Avalanche Zener Both a and b None of the above None Hint 3). Which one of the following breakdown voltages is directly proportional to the temperature? Avalanche Zener Both a and b None of the above None Hint 4). The existence of an electric field is more on the ______________ breakdown Avalanche Zener Both a and b None of the above None Hint 5). Which one of the following is a type of reverse breakdown in the zener diode? Avalanche Zener Both a and b None of the above None Hint 6). ______________ are the few applications of zener diode Used in voltage regulators Used in electronic devices Used as a voltage reference device All of the above None Hint 7). What are the advantages of zener diode? Has very high-efficiency Less expensive Smaller in size All of the above None Hint 8). In which direction does the zener diode operate? Forward bias Reverse bias Both a and b None of the above None Hint 9). In forward bias condition the zener diode will work as a ______________ Conventional diode Laser diode PN diode None of the above None Hint 10). The L or H is the measuring unit of ____________ parameter Capacitance Resistance Insulator Inductance None Hint 11). In which breakdown the breakdown voltage decreases with an increase in temperature? Zener PN junction Both a and b None of the above None Hint 12). Which one of the following breakdowns is caused by field ionization? Zener PN junction Both a and b None of the above None Hint 13). The electrons in ______________ breakdown, pulled from valance to conduction band Zener PN junction Both a and b None of the above None Hint 14). What are the advantages of the series regulator? Higher current stability Simple to design Both a and b None of the above None Hint 15). What are the disadvantages of three-terminal regulators? Less efficient Higher current require larger packages Both a and b None of the above None Hint 16). What are the disadvantages of the series regulators? Higher current stability Simple to design Inefficient None of the above None Hint 17). An ideal diode in forward bias have _________ resistance Infinite Finite Zero None of the above None Hint 18). In which breakdown the breakdown voltage increase with an increase in temperature? Zener PN junction Avalanche None of the above None Hint 19). Which one of the following breakdowns is caused by impact ionization? Zener PN junction Avalanche None of the above None Hint 20). The change in voltage is given by _______________ Iz(max)=Vz+ΔVz ΔVz=ΔIz*Zz Iz(max)=Vin-Vz(max)/R None of the above None Hint 21). What are the advantages of the three-terminal regulators? Fewest parts Lowest output noise Lowest ripple All of the above None Hint 22). An ideal diode in reverse bias have _________ resistance Infinite Finite Zero None of the above None Hint 23). The PN junction in forward bias offers ______________ resistance High Low Very low Very high None Hint 24). What are the disadvantages of the zener diode? Fewer parts Simpler construction Low current All of the above None Hint Read more about Diodes 25). The depletion layer in reverse bias is _______________ Very thin Thin Thick None of the above None Hint Zener Diode Important MCQs 26). The rectifier diode forward voltage drop is between _________________ 1 to 2 Volts 0.7 to 0.9 Volts 10 to 20 Volts 5 to 22 Volts None Hint 27). How many types of zener analyses are there? One Two Three Four None Hint 28). What are the advantages of the three-terminal regulators? Lightweight Higher efficiency Small in size All of the above None Hint 29). The PN junction in reverse bias offers ______________ resistance High Low Very low Very high None Hint 30). Which one of the following has only diodes? Controlled rectifier Half controlled rectifier Uncontrolled rectifier None of the above None Hint 31). Which one of the following breakdowns occurs in both rectifier and zener diodes? Avalanche Zener PN junction All of the above None Hint 32). The uni-junction transistor is a simple _____________ layer transistor One Two Three Four None Hint 33). The uni-junction transistor used to trigger _________________ SCR Pulse circuitry Both a and b None of the above None Hint 34). The depletion layer in forward bias is _______________ Very thin Very thick Thick None of the above None Hint 35). How many types of MOSFET’S are there? One Two Three Four None Hint 36). Which one of the following is the unit of DC? Q=C*V F=1/T T=1/f R=V÷I None Hint 37). The FET devices are divided into _________________ types One Two Three Four None Hint 38). ______________ are the various biasing circuits Fixed bias current Fixed bias with emitter resistor Collector to base bias circuit, and potential divider bias circuit All of the above None Hint 39). The three-layer semiconductor devices consists _____________ layers of material 2-N and 1-P type 2-P and 1-N type Both a and b None of the above None Hint 40). The simple PN junction has _____________ types of bias One Two Three Four None Hint 41). How many types of bias does two PN junction device have? One Two Three Four None Hint 42). The half-wave rectifier output DC voltage calculated by ____________ formula Vpeak/4π Vpeak/π Vpeak/8π None of the above None Hint 43). How many types of resistances are there? One Two Three Four None Hint 44). The common zener voltages are from ___________ 1 to 20 V 10 to 20 V 1.8 to 200 V 1 to 10 V None Hint 45). The zener operated in reverse bias at PIV is known as ___________ Zener current Zener voltage Both a and b None of the above None Hint 46). The current controllable type and voltage controllable type are the two types of ___________ device Negative resistance Positive resistance Negative or positive resistance None of the above None Hint 47). The avalanche breakdown occurs at ____________ volts >1V >5V >20V >30V None Hint 48). Which one of the following breakdowns occurs in highly doped diodes? Zener Avalanche Both a and b None of the above None Hint 49). Which one of the following breakdowns has a sharp curve in VI characteristics? Zener Avalanche Both a and b None of the above None Hint 50). In _____________ breakdown, when the temperature increases the breakdown voltage decreases Zener Avalanche Both a and b None of the above None Hint Zener Diode MCQs for Quiz 51). The temperature coefficient in zener breakdown is _________ Positive Negative Positive and negative Always positive None Hint 52). The zener breakdown occurs at ____________ volts >1V <5V >20V >30V None Hint 53). The doping density is high in ___________ breakdown Zener Avalanche Both a and b None of the above None Hint 54). Which one of the following breakdowns doesn’t affect the voltage? Zener Avalanche Both a and b None of the above None Hint 55). The advantages of zener diode are ___________ Fewer parts Construction is simple Both a and b None of the above None Hint Read more about Zener Diode 56). Which one of the following breakdowns occurs in lightly doped diodes? Zener Avalanche Both a and b None of the above None Hint 57). In _____________ breakdown, when the temperature increases the breakdown voltage increases Zener Avalanche Both a and b None of the above None Hint 58). The temperature coefficient in avalanche breakdown is _________ Positive Negative Positive and negative Always negative None Hint 59). The production of a pair of holes & electrons takes place in __________ breakdown Zener Avalanche Both a and b None of the above None Hint 60). The doping concentration is high in ______________ breakdown Zener Avalanche Both a and b None of the above None Hint 61). The electric field is strong in ____________ breakdown Zener Avalanche Both a and b None of the above None Hint 62). The temperature of zener breakdown and the breakdown voltage is inversely proportional to each other in ______________ breakdown Zener Avalanche Both a and b None of the above None Hint 63). Which one of the following is a type of solid dielectric breakdown? Electrical & thermal breakdown Electrochemical & electromechanical breakdown Erosion breakdown All of the above None Hint 64). ______________ are the subtypes of electrical breakdown Intrinsic breakdown Avalanche breakdown Both a and b None of the above None Hint 65). _____________ are the characteristics of intrinsic breakdown Valid at low temperature Independent of sample thickness & electrode configuration Time delay from picosecond to nanosecond All of the above None Hint 66). ________________ are the few applications of avalanche diode Voltage reference Microwave frequency generator RF noise generator All of the above None Hint 67). The production of electrons takes place in __________ breakdown Zener Avalanche Both a and b None of the above None Hint 68). ________________ are the few applications of Schottky diode Power OR circuits Power rectifier Solar cell applications All of the above None Hint 69). The avalanche breakdown occurs in ________________ Semiconductor materia Insulating material Both a and b None of the above None Hint 70). Which one of the following breakdowns is a type of electron avalanche? Zener Avalanche Both a and b None of the above None Hint 71). The zener diode is also called as _____________ diode Breakdown voltage of a diode Breakdown diode Breakdown voltage of diode or breakdown diode None of the above None Hint 72). In zener diode the voltage tolerance is typically ___________ ±1% ±2% ±3% ±5% None Hint 73). The maximum power rating in zener diode is _________________ 10W 2W 100W None of the above None Hint 74). The avalanche breakdown voltage is ____________ volts for the zener One Two Four Six None Hint 75). The voltage after the breakdown is known as ___________ voltage Zener Avalanche Both a and b None of the above None Hint Zener Diode Important MCQ’s for Exams 76). How many types of power supplies are there? One Two Four Six None Hint 77). The doping density is low in ___________ breakdown Zener Avalanche Both a and b None Hint 78). The temperature of avalanche breakdown and the breakdown voltage is inversely proportional to each other in ______________ breakdown Zener Avalanche Both a and b None of the above None Hint 79). ______________ are the basic parts of automatic voltage regulator Error detecting element Stabilizing element Correcting element All of the above None Hint 80). How many terminals does the zener diode have? One Two Four Six None Hint 81). Which one of the following is a correct formula for zener maximum current? Pzmax/Vz Pzmax*Vz Pzmax-Vz None of the above None Hint 82). Which one of the following breakdowns occurs at relatively low reverse voltage? Zener Avalanche Both a and b None of the above None Hint 83). _____________ formula is used to calculate the minimum zener voltage Vz(min)=Vz-ΔVz Vz(min)=Iz-ΔVz Vz(min)=ΔVz None of the above None Hint 84). The electrons in ______________ breakdown, pulled from conduction to valance band Zener PN junction Avalanche None of the above None Hint 85). The minimum value of load resistance is calculated by _____________ Zener voltage divided by maximum load current Zener voltage divided by minimum load current Load current divided by maximum zener voltage None of the above None Hint 86). _____________ formula is used to calculate the minimum zener current Iz(max)=Vz+ΔVz Iz(max)=Vin-Vz(min)/R Iz(max)=Vin-Vz(max)/R None of the above None Hint 87). Which one of the following is a correct formula for maximum power dissipation of a zener? Pzmax/Iz Pzmax*Iz Vz*Izmax None of the above None Hint 88). _____________ formula is used to calculate the maximum zener current Iz(max)=Vz+ΔVz Iz(max)=Iz-ΔVz Iz(max)=Vin-Vz(max)/R None of the above None Hint 89). Which one of the following has both diodes and thyristor? Controlled rectifier Half controlled rectifier Uncontrolled rectifier None of the above None Hint 90). Which one of the following is a formula for maximum zener current? Power/Voltage Power rating/Zener voltage Zener current/Zener Voltage None of the above None Hint 91). The R or Ω is the measuring unit of ____________ parameter Capacitance Resistance Insulator None of the above None Hint 92). Which one of the following diodes conducts only in one direction? Zener PN junction Both a and b None of the above None Hint 93). Which one of the following is the unit of electrical charge? Q=C*V F=1/T T=1/f None of the above None Hint 94). The FET was known as a _____________ transistor Unipolar Bi-polar Unipolar or bipolar None of the above None Hint 95). How many types of zener diode regulators are there? One Two Three Four None Hint 96). The doping at the junction is minimum in _____________ breakdown Zener Avalanche Both a and b None of the above None Hint 97). The tunneling effect takes place in __________ breakdown Zener Avalanche Both a and b None of the above None Hint 98). _____________ formula is used to calculate the maximum zener voltage Vz(max)=Vz+ΔVz Vz(max)=Iz-ΔVz Vz(min)=ΔVz None of the above None Hint 99). Which one of the following doesn’t have units or dimensions? Dielectric constant Dielectric strength Both a and b None of the above None Hint 100). In normal diodes, the doping intensity is ____________ compare to zener diode High Very high Moderate low None Hint Time's up