MOSFET Question & Answers August 4, 2021 By WatElectronics This article lists 100 MOSFET MCQs for engineering students. All the MOSFET Questions & Answers given below includes solution and link wherever possible to the relevant topic. A FET (Field Effect Transistor) is a class of transistors that overcomes the disadvantage of the BJT transistor. It is capable of transferring high quantity resistance to low quantity resistance and exhibits unipolarity. It comprises of 3 main terminals source, drain, and gate. Where the source is the input terminal, the gate is the controller of FET and the drain is the external terminal. It is classified into two 2 types namely JFET and MOSFET, where JFET is further classified as n-type and p-type JFET, and MOSFET is also classified as N-type Enhancement MOSFET and P-type Enhancement MOSFET. Where these FETs are biased in two ways either fixed, self, or potentially biased. In a fixed bias, the FET is connected to the battery externally for its operation, and in self-bias, it does not require any external battery to operate and in a potential bias, the bias is provided by an external source and is divided using resistors. A FET usually operates in 4 main regions ohmic, saturation, cutoff region, and breakdown region. It has certain disadvantages like higher resistance at the drain & slow operation. To overcome this, a MOSFET is designed. These can be used in both analog and digital monolithic Integrated circuits as active components and distinct devices. It is manufactured with 'controlled oxidation of the semiconductor typically using silicon. 1). What are the disadvantages of Field Effect Transistors? Higher resistance at drain Operation is slow Impedance at input is moderate All as mentioned earlier Hint 2). Who introduced ‘First Vertical Power MOSFET’? Mohammed Atalla Dawon Kahng Hitachi a & b Hint 3). What does MOSFET stands for? Metal Oxide Semiconductor Field Effect Transistor Modern Oxidized Silicon based Field Effect Transistor Modern Oxidized Silicon based Force Effect Transistor Metal Oxide silicon Field Equivalent Transistor Hint 4). What type of a device is MOSFET? Current-controlled Voltage-controlled Voltage-controlled Current source Voltage-controlled Voltage source Hint 5). What type of carriers are controlled in a MOSFET? Majority Minority Both Majority & Minority Either Majority or Minority Hint 6). How many terminals does a MOSFET possess? One Two Three Four Hint 7). What are the main terminals that carry current? Source Drain Source & Drain Gate Hint 8). What type of MOSFETs preferred for Power electronics? Enhancement Depletion P-channel Depletion N-channel Depletion Hint 9). Which layer isolates terminal Gate from semiconductor? Silicon oxide Silicon dioxide Silicon Silica Hint 10). MOSFET is a __________ device. Tri-terminal Unipolar Voltage-controlled All as mentioned earlier Hint Read More About MOSFET 11). Which transistor is preferred for applications of High power? BJT UJT MOSFET JFET Hint 12). What type of transistors are commonly used in digital and the analog circuits? BJT UJT MOSFET JFET Hint 13). ____________ are normally referred to as ON switches. JFET UJT Depletion MOSFET Enhancement MOSFET Hint 14). Which substrate does a n-channel made device possess? P-type N-type Both P & N-type Can’t say Hint 15). Which Transistor is used in VLSI? JFET UJT MOSFET CMOS Hint 16). Which transistor offer highest speed? JFET UJT MOSFET CMOS Hint 17). What is required to switch OFF the MOSFET (Depletion type)? VGS VDS VGD Either VDS or VGD Hint 18). Which one is referred to as Open switch? JFET UJT Depletion MOSFET Enhancement MOSFET Hint 19). Unbroken Line in the symbol of MOSFET known as _____ MOSFET. Depletion Enhancement ON switch (normally) a& c Hint 20). What is represented by the line amid Source and Drain? Conductive channel Non-conductive channel Semi conductive channel Any type of channel Hint 21). What happens to line of channel in Enhancement MOSFETs? Broken Unbroken Dotted a & c Hint 22). What differentiates ‘N-type’ and ‘P-type’ MOSFETs? Arrow direction Line in MOSFET Mode Data insufficient Hint 23). In which class does MOSFETs work as amplifier? Class-A Class-B Class-C Class-D Hint 24). At VGS =0, what happens to the channel of Depletion MOSFETs? Conduct Doesn’t conduct Rarely conduct Insulate Hint 25). In which MOSFET the channel gates depleted for –VGS ? P-channel Enhancement N-channel Enhancement P-channel Depletion N-channel Depletion Hint MOSFET MCQs with Answers 26). In which MOSFET the channel gates depleted for +VGS ? P-channel Enhancement N-channel Enhancement P-channel Depletion N-channel Depletion Hint 27). What type of MOSFETs possess Undoped or Lightly doped channel? Depletion Enhancement ON switch (normally) a& c Hint 28). What condition makes MOSFET a Transconductance device? VGS> VTH VGS<VTH VGS=VTH VGS= 0 Hint 29). Transistor is OFF in P-channel eMOSFET for? +VGS -VGS VGS<VTH VGS= 0 Hint 30). What are the different regions MOSFET operate? Cut-off Linear Saturation All as mentioned earlier Hint Read More About P-Channel MOSFET 31). What is the condition of Cut-off region? VGS> VTH VGS<VTH VGS=VTH VGS= 0 Hint 32). What do you name MOSFET with n-channel? PMOS CMOS NMOS Bi CMOS Hint 33). What condition satisfies Saturation region? VGS> >VTH VGS<VTH VGS=VTH VGS= 0 Hint 34). MOSFET in Cut-off region works as _______. Close switch Open switch Amplifier Switch Hint 35). What is the condition of Linear region? VGS>VTH VGS<VTH VGS=VTH VGS= 0 Hint 36). In which region MOSFETs perform ‘Switching’? Cut-off Linear Saturation b & c Hint 37). Depletion mode MOSFETs can operate in __________ mode. Enhancement Depletion Enhancement and Depletion Can’t say Hint 38). Which substrate used in MOSFETs of n-channel? P N P+ N+ Hint 39). Where the Metallic gate is deposited in MOSFETs? Substrate Electrodes Oxide layer Terminals Hint 40). MOSFET is _______. Unidirectional Bidirectional Unipolar b & c Hint 41). In which region IDS & VDS are dependent? Cut-off Ohmic Saturation a & c Hint 42). MOSFETs as Amplifiers operate in which region? Cut-off Ohmic Saturation a & c Hint 43). Of which region IDS remains constant? Cut-off Ohmic Saturation Linear Hint 44). Which is known as Control terminal in MOSFET? Source Drain Gate Body Hint 45). When are MOSFETs are preferred? Low voltage High Frequency a and b High voltages Hint 46). Which determine the rise & fall timings of voltage at drain? Input capacitor Gate resistance Resistor Transfer capacitor Hint 47). What are used in MOSFETs to determine current fall and rise timings while switching? Input capacitor Gate resistance Resistor a & b Hint 48). What can destroy Gate Oxide Layer? Static charge Dynamic charge Random Charge Either static or dynamic Hint 49). What happens to MOSFET in safe area of operating? Doesn’t change in Forward bias Doesn’t change in Reverse bias a & b Change in Forward and Reverse bias Hint 50). Why Switching delays occur in MOSFET? Finite Charging Time Finite Discharging Time Finite Discharging and Charging Time Data insufficient Hint MOSFET Interview Questions & Answers 51). What are the majority carriers in n-channel MOSFET? Holes Electrons Holes & Electrons Protons Hint 52). MOSFETs doesn’t undergo ___________. Breakdown First breakdown Second breakdown No breakdown occurs Hint 53). What happens to the Leakage current in MOSFET? Small Large Very small Very large Hint 54). What is the minimum amount of voltage required to operate MOSFET? Positive voltage Negative voltage Threshold voltage Breakdown voltage Hint 55). What type of device is MOSFET? Active device Passive device Reactive device Neither a nor b Hint 56). Which MOSFET doesn’t have channel? Depletion type Enhancement type P-Channel N-Channel Hint 57). What happens to noise in MOSFET? High Low Moderate Large Hint 58). What happens to width of channel when negative voltages applied at gate of MOSFET? Less Very less Moderate Large Hint 59). Enhancement MOSFET operates in _____ modes Conducting Non-Conducting Conducting and Non-conducting Partially conducting Hint 60). What happens to Transconductance in MOSFETs compared to BJTs? Low Very Low Moderate Large Hint 61). Amplifiers made of Depletion MOSFETs resembles _____. BJT amplifiers FET amplifiers JFET amplifiers b & c Hint 62). On what MOSFET working depend? MOS Transistor MOS Capacitor MOS Resistor MOS Voltage Hint 63). Which type of voltage induce channel in ‘n-channel’ Enhancement MOSFET? Positive voltage Negative voltage Threshold voltage Zero voltage Hint 64). How the channel’s conductivity enhanced in E MOSFET? Decrease in VGS Increase in VGS Constant VGS Zero VGS Hint 65). What happens to channel in EMOSFET if VGS applied is below threshold? Enhanced conductivity Conductivity is high No channel detected Channel is fixed Hint 66). Depletion MOSFET conducts when_______. VGS>VTH VGS<VTH VGS>0 VGS= 0 Hint 67). LD MOSFET is an acronym of? Laterally Diffused MOSFET Linearly Dependent MOSFET Linearly Diffused MOSFET Linearly Doped MOSFET Hint 68). Which device has short channel? JFET BJT UJT LDMOSFET Hint 69). What type of transistors are scaled to small dimensions? BJT FET UJT MOSFET Hint 70). MOSFET is also referred to as ________. FET UJT MESFET IGFET Hint 71). IGFET stands for _______. Insulated Gate Field Effect Transistor Independent Gate Field Efficiency Transistor Insight Gate Field Efficiency Transistor Insulated Gate Field Effective Transistor Hint 72). On what basis MOSFET characteristics depend on? Depletion type Enhancement type a & b Can’t say Hint 73). What are the benefits of short channel in LDMOSFETs? Low Resistance Tolerate high currents Tolerate high voltage All as mentioned earlier Hint 74). VMOSFETs has _______ connections of source. One Two Three Four Hint 75). When a MOSFET (n-channel) operates in First Quadrant? Positive voltage at Drain Negative voltage at Drain Positive voltage at Source Positive voltage at Gate Hint MOSFET MCQs for Exams 76). MOS Technology is based on _____. SRAM DRAM ROM EPROM Hint 77). While the study of Characteristics of MOSFET what is found? MOS capacitor MOS Transistor MOS resistor MOS Memory Hint 78). What are used in the production of Reprogrammable ROM? FGMOS PMOS NMOS CMOS Hint 79). FGMOS stands for ________. Fluctuation-Gate MOSFET Floating-Gate MOSFET Functional-Gate MOSFET Floating-Gunn MOSFET Hint 80). What type of memories are designed using FGMOS? Flash Memory ROM EPROM All as mentioned earlier Hint 81). What happens to MOSFET when the flow of current is absent at terminal Gate? Voltage Controlled Resistor Current Controlled Resistor Voltage Controlled Capacitor Current Controlled Capacitor Hint 82). What works as Conducting channel in MOSFET? Physical layer Transmission layer Inversion layer Data insufficient Hint 83). With p variant substrate what does Inversion charge consists of? Electrons Holes Protons Neutrons Hint 84). Depletion region & substrate (neutral) are isolated by? AC Conditions DC Conditions Gate voltage Zero voltage Hint 85). GCA stands for _______. Gradual Channel Approximation Gradual Component Approximation Gratitude Channel Allocation Gradual Channel Allocation Hint 86). GCA of MOSFETs is acceptable for? Short-channel Long-channel a & b Moderate-channel Hint 87). How the capacitor gets charged in the MOSFET circuit of Switching? Applied VGS Applied VDS Applied Positive Voltage Applied Negative Voltage Hint 88). When is Power handling capacity limited? MOSFET On MOSFET Off MOSFET On & Off Can’t say Hint 89). What classifies the mode in MOSFETs? Applied Voltage Capacitor connected P & N channels Resistor connected Hint 90). Can a Microcontroller drive MOSFET (p-channel)? Yes No Impossible Can’t say Hint 91). What does the arrow on MOSFETs symbol indicate? Electron direction Voltage polarity Variant of MOSFET Conventional flow of current Hint 92). Chopper circuits prefer _________. BJT UJT Diode MOSFET Hint 93). Which is considered as the basic block of Digital Electronics? Diode Resistor Capacitor MOSFET Hint 94). What can be the disadvantages of a MOSFET? Damage due to Static charge Unstable (Overload voltages) a & b High impedance at input Hint 95). The speed of switching in MOSFET is _____. Low High Moderate Can’t say Hint 96). What are important aspects of using a MOSFET? Great efficiency Can operate at low voltages High impedance at input All as mentioned earlier Hint 97). What is preferred for the regulation of DC Motors? BJT UJT MESFET Power MOSFET Hint 98). Which amplifiers are preferred during Radio frequency applications? FET UJT MESFET MOSFET Hint 99). CMOS stands for ___________. Complementary Metal Oxide Semiconductor Commutative Metal Oxide Semiconductor Cosmopolitan MOS Customize MOS Hint 100). What is BiCMOS? Combination of PMOS & NMOS Combination of BJT & JFET Combination of BJT & CMOS Combination of BJT & UJT Hint Time is Up! Time's up
