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Right option is (a) 5

To explain I would say: BICMOS is a combination of both CMOS and BJT TECHNOLOGY. The BiCMOS family has MAINLY 5 members and those are ABT logic, ALB logic, ALVT logic, BCT logic and LVT logic.

Right answer is (a) Large fan-out

Easiest explanation: Fan-out is the measure of the maximum number of inputs that a SINGLE gate output can FEED. BiCMOS CIRCUITS are PARTICULARLY useful for LOGIC with large fan-out (large capacitive load).

The correct ANSWER is (a) logic 0

To explain: RTL NOR gate behaves as NOR gate and the OUTPUT of NOR gate will be 1 only when all the inputs are at logic 0. The output of NOR will be 0 if any of the INPUT is 1.

Right option is (b) ECL 100K

Explanation: The latest entrant to the ECL family is ECL 100K, having 6-digit part numbers. This family offers functions, in general, different from those offered by 10K series. This family operates with a reduced power supply VOLTAGE -4.5 V, has shorter propagation delay of 0.75 ns, and transition TIME of 0.7 ns. HOWEVER, the power consumption per gate is about 40 mW.

Correct answer is (c) 5

To explain I would SAY: Motorola has offered MECL circuits in five logic FAMILIES: MECL I, MECL II, MECL III, MECL 10000 (MECL 10K) and MECL 10H000 (MECL 10KH). The full form of MECL is Motorola emitter coupled logic. ECL is a high speed BJT. It USES BJT differential amplifier with single INPUT and restricted current to avoid the transistor going into saturation and thus turning off operation.

Correct answer is (b) Motorola EMITTER coupled logic

To explain I would say: The full form of MECL is Motorola emitter coupled logic. ECL is a high speed BJT. It USES BJT DIFFERENTIAL amplifier with single input and restricted current to avoid the transistor going into saturation and THUS TURNING off operation.

Right CHOICE is (d) Schottky diodes

To EXPLAIN: Schottky FAMILIES prevent the saturating USING Schottky diodes across the base-collector junctions of transistors. In Saturation mode, the transistor is in “ON”mode, where it seems like a short circuit between collector and emitter.

The correct option is (c) Saturation

The best I can explain: The key to propagation delay in bipolar logic family is to prevent the transistors in a gate from saturation. In Saturation mode, the TRANSISTOR is in “ON”mode, where it SEEMS like a short CIRCUIT between collector and EMITTER.

The correct OPTION is (B) Consume too much power

For explanation I would say: Commercial ECL families are not nearly as popular as TTL and CMOS mainly because they consume too much power. CMOS CONSUMES the LEAST power while TTL provides high speed.

The correct choice is (B) Interface

The BEST I can explain: The method of CONNECTING a driving device to a loading device is known as interface. The output(s) of a circuit or a system should match the input(s) of another circuit or system that has different ELECTRICAL characteristics. This is referred to as compatibility.

Right choice is (C) Complemented Voltage Switch Logic

Easy explanation: Cascode Voltage Switch Logic (CVSL) refers to a CMOS-type logic family which is designed for certain advantages. It requires mainly N-channel MOSFET TRANSISTORS to implement the logic using true and COMPLEMENTARY input signals and also NEEDS two P-channel transistors at the top to pull one of the outputs HIGH.

The CORRECT option is (a) The OUTPUT of a circuit should MATCH with the input of another circuit

Easy explanation: The output(s) of a circuit or a system should match the input(s) of another circuit or system that has DIFFERENT electrical characteristics. This is referred to as COMPATIBILITY.

The correct option is (C) Pass transistor logic

Easiest explanation: The FULL form of PTL is “pass transistor logic”. It combines different logic families to design an INTEGRATED circuit. THUS, it reduces the NUMBER of transistors used by scraping off the unnecessary transistors.

Correct choice is (C) ADVANCED version of LVT logic

To elaborate: ALVT stands for Advanced Low Voltage BiCMOS Technology (ALVT). It is a faster version of LVT family. It is an integration of LESS POWER dissipation and less noise of CMOS ALONG with the high switching speed and output drive of BJT.

Correct option is (d) All of the Mentioned

The best EXPLANATION: CMOS ensures low power dissipation, SMALLER NOISE margin and higher packaging density. It also offers high input resistance and is excellent for constructing simple, low-power LOGIC gates.

Right choice is (c) BiCMOS

The best explanation: The Pentium technology is based on BiCMOS technology because BiCMOS circuits use the CHARACTERISTICS of each type of transistor most appropriately. CMOS ENSURES low power dissipation, smaller noise margin and higher packaging density, while BJT OFFERS high SWITCHING speed and improved noise PERFORMANCE.

Right choice is (a) 1990

To explain I would say: BICMOS technology was introduced in 1990s. BiCMOS is an evolved semiconductor technology that integrates two formerly separate semiconductor technologies those of the BJT and CMOS. CMOS ensures low power DISSIPATION, smaller noise margin and higher packaging density, while BJT offers high SWITCHING speed and IMPROVED noise performance.

The correct option is (c) Lower supply voltage while RETAINING TTL logic levels

For EXPLANATION I would say: LVT stands for Low Voltage BiCMOS Technology which is an integration of less power dissipation and less noise of CMOS along with the high SWITCHING speed and output DRIVE of BJT. LVT logic is nothing but the lower supply voltage while retaining TTL logic levels.

Right option is (d) All of the Mentioned

To elaborate: BIPOLAR junction transistors offer HIGH SPEED, high gain and low output resistance, which are excellent properties for high-frequency analog amplifiers. It also offers high switching speed and IMPROVED noise performance.

Right choice is (c) BJT and CMOS

For explanation: BiCMOS is an evolved SEMICONDUCTOR technology that integrates TWO formerly SEPARATE semiconductor technologies those of the BJT and CMOS. CMOS ensures low POWER dissipation, smaller noise margin and higher packaging density, while BJT OFFERS high switching speed and improved noise performance.

Correct option is (C) The Motorola 146818

Explanation: The Motorola 146818 was the first RTC and CMOS RAM chip to be used in early IBM COMPUTERS; CAPABLE of storing a total of 64 bytes.

The correct option is (a) GE and Si

The BEST I can EXPLAIN: Semiconductors are made of Silicon (Si) and Germanium (Ge). Semiconductors are devices having CONDUCTIVITY between conductors and insulators.

Correct choice is (b) LESS

Easiest explanation: CMOS logic dissipates less power than NMOS logic circuits because CMOS dissipates power only when SWITCHING (“DYNAMIC power”). THUS, CMOS has less power consumption and is more efficient.

The correct choice is (B) Duality

The EXPLANATION is: An IMPORTANT characteristic of a CMOS circuit is the duality that exists between its PMOS transistors and NMOS transistors. Due to the presence of two DIFFERENT types of transistors, the device has a complementary function.

Correct OPTION is (c) Inverter

The explanation: SINCE, the OUTPUTS of the PMOS and NMOS transistors are complementary such that when the INPUT is low, the output is high and when the input is high, the output is low. Because of this behaviour of input and output, the CMOS circuit’s output is the inverse of the input. Whereas, adders and subtractors are combinational circuits.

Right choice is (d) Both high noise immunity and low static power consumption

Explanation: TWO important characteristics of CMOS devices are high noise immunity and low static power consumption. SINCE one transistor of the pair is always off and the SERIES combination draws significant power only momentarily during switching between on and off states. Also, the performance of CMOS is not ALTERED with the presence of noise and thus it has high noise immunity.

The correct option is (d) Both microprocessor and digital LOGIC

To explain: CMOS technology is used in Microprocessor, Microcontroller, STATIC RAM and other digital logic circuits. CMOS technology is also used for several analog circuits such as image SENSORS (CMOS sensor), data converters and highly integrated TRANSCEIVERS for many types of communication.

Correct choice is (c) Complementary symmetry metal oxide semiconductor

To explain I would SAY: CMOS is also SOMETIMES referred to as complementary SYSTEMATIC metal oxide–semiconductor (COS-MOS). In this type of DEVICE, both n-type and p-type transistors are used in a complementary way. USUALLY, the transistors used are MOSFETs.

Correct choice is (C) COMPLEMENTARY METAL OXIDE semiconductor

To explain: The full form of CMOS is complementary metal oxide semiconductor. In this type of device, both n-type and p-type transistors are used in a complementary WAY.

The correct option is (a) Complementary symmetry metal oxide semiconductor

The explanation is: The full FORM of COS-MOS is complementary SYSTEMATIC metal oxide semiconductor. In this type of device, both n-type and p-type TRANSISTORS are USED in a complementary WAY. Usually, the transistors used are MOSFETs.

Correct option is (d) Both LSI and VLSI

For explanation: SINCE more TRANSISTOR and CIRCUITRY functions can be achieved on a single CHIP with MOS technology that is why MOS is being used in LSI and VLSI. LSI stands for LARGE Scale Integration and VLSI stands for Very Large Scale Integration.

Right choice is (a) MOSFET has low packing density

For EXPLANATION: MOSFET is preferred over BJT because of its low packaging density.Thus, more NUMBER of MOSFET MEMORY cells can be accommodated in a PARTICULAR area as compared to BJT.

The correct answer is (b) Use of SILICON NITRIDE

The best I can explain: Silicon nitride is sandwiched between two SiO2 layer and provide NECESSARY barrier. The dielectric constant of Si3N4 is 7.5, whereas that of SiO2 is 4. This increase in overall dielectric constant reduces threshold voltage.

Correct CHOICE is (b) Threshold voltage

The EXPLANATION is: In MOSFET, the threshold voltage is typically 3 to 6V. This large voltage is not COMPATIBLE with the supply of 5V which is used in digital ICs. So, for the improvement of the device’s PERFORMANCE the magnitude of threshold voltage should be reduced.

The correct choice is (c) Silicon dioxide

Explanation: Silicon dioxide is USED as an insulating layer in the fabrication of MOSFET. It GIVES an EXTREMELY high input RESISTANCE in the order of 10^10 to 10^15 Ω for MOSFET.

Right answer is (d) All of the mentioned

Explanation: MOSFET are of two types: ENHANCEMENT and depletion type. Further, these are CLASSIFIED into n-type and p-type DEVICE. The depletion type is switched on without the application of gate BIAS voltage and the enhancement type is switchedon with the application of gate voltage.

The correct option is (a) Metal OXIDE semiconductor

Explanation: The FULL FORM of MOS is “Metal Oxide Semiconductor”. It is a type of transistor having 3 layers: a metal CONDUCTOR, an insulating SILICON layer and a semiconductor silicon layer.

Correct answer is (a) A two-input NOR gate

Easy EXPLANATION: When the outputs of two inverters are wired TOGETHER then the result is a two-input NOR gate because the configuration (NOT A) AND (NOT B) is equivalent to NOT (A OR B). In a NOR gate, the output is high only when all of its input are at logic 0 else, the output is LOW.

The correct option is (c) MOTOROLA

Explanation: I2L is relatively simple to construct on an INTEGRATED CIRCUIT and was commonly used before the ADVENT of CMOS LOGIC by companies such as Motorola.

Correct option is (B) BASE

To elaborate: In IIL, the INPUT is SUPPLIED to the base as either a current sink (low logic level) or as a high impedance floating condition (high logic level). The output of an INVERTER is connected to the collector.

The correct CHOICE is (d) I TWO L

To EXPLAIN: The full form of IIL is Integrated INJECTION logic. It is made up of multiple bipolar JUNCTION transistors and had speed comparable to TTl and power consumption equivalent to CMOS. Integrated Injection logic can be DENOTED as IIL, I^2L and I2L as well.

Correct option is (c) MERGED transistor logic

The explanation: The full FORM of IIL is Integrated INJECTION logic. It is made up of multiple bipolar junction transistors and had speed comparable to TTl and power consumption EQUIVALENT to CMOS. IIL is sometimes also known as merged transistor logic.