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Right answer is (a) High

To explain I would say: 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 has high noise immunity because it OPERATES by CURRENT instead of voltage.

The correct CHOICE is (C) Integrated INJECTION logic

The best explanation: The full form of IIL is Integrated injection logic. It is made up of multiple bipolar junction transistors and had a speed comparable to TTl and POWER consumption EQUIVALENT to CMOS.

The correct answer is (c) PECL

Easy explanation: Low voltage positive EMITTER coupled logic (LVPECL) is a power optimized VERSION of PECL using a +3.3 V instead of 5 V supply.

Correct option is (a) NEGATIVE voltage

Best explanation: The ECL circuits usually OPERATE with negative power supplies (positive end of the supply is connected to ground), in COMPARISON to other logic families in which negative end of the supply is grounded. It is done mainly to MINIMIZE the influence of the power supply VARIATIONS on the logic levels as ECL is more sensitive to noise on the VCC and relatively immune to noise on VEE.

The CORRECT OPTION is (c) 1956, Hannon S. Yourke

To explain I would SAY: ECL was invented in August 1956 at IBM by Hannon S Yourke.

Correct answer is (b) SCFL

To explain I would say: The equivalent of emitter-coupled LOGIC made out of FETS is called Source-coupled logic(SCFL). Like ECL, SCL is also the FASTEST among the logic FAMILIES.

Correct choice is (b) Source-coupled LOGIC

To explain: The full FORM of SCFL is source-coupled logic.

The correct option is (a) It requires more power

For explanation: ECL’s major disadvantage is that each gate CONTINUOUSLY DRAWS CURRENT, which means it requires (and dissipates) significantly more power than those of other logic families. But ECL logic gates have clock frequency. Thus, they have a fast operation.

The CORRECT answer is (c) Collector

The EXPLANATION is: THOUGH, the EMITTER and collector of the ECL are COUPLED together. So, the output will be taken from a collector.

Right choice is (b) NOR gate

The best I can explain: The ECL BEHAVES as NOR gate because if any of the input voltages go HIGH as COMPARED to the REFERENCE voltage, the output is low and the output is high only when all the input voltages are low.

The correct option is (a) HIGH

The best I can explain: If the input impedance is high and the output resistance is low; as a RESULT, the transistors change states QUICKLY, GATE delays are low, and the fanout capability is high. Fan-out is the measure of the maximum number of inputs that a single gate output can accept.

Right option is (C) CML

The explanation is: ECL (Emitter Coupled Logic) can ALSO be named as CML(COLLECTOR Mode Logic).

Correct option is (b) ECL

Easy EXPLANATION: ECL is the fastest of all the logic families because of the emitters of many TRANSISTORS are coupled together which results in the HIGHEST transmission RATE.

Correct ANSWER is (C) Emitter-coupled logic

Best EXPLANATION: The FULL form of ECL is emitter-coupled logic.

Correct option is (C) COLLECTOR mode logic

To explain: The FULL form of CML is Collector Mode Logic.

Correct choice is (b) Analog amplifier

Easy EXPLANATION: A TTL gate MAY operate INADVERTENTLY as an analog amplifier if the INPUT is CONNECTED to a slowly changing input signal that traverses the unspecified region from 0.7V to 3.3V.

Right answer is (a) Current sinking

To explain: Like DTL, TTL is a current-sinking LOGIC since a current must be drawn from INPUTS to bring them to a logic 0 level. Current SINK means it ACCEPTS current coming out from a source.

The CORRECT answer is (B) More

The BEST I can explain: TTL devices consume substantially more power than equivalent CMOS devices at REST. Thus, CMOS devices are faster than TTL devices.

Right choice is (c) 5

To elaborate: STANDARD TTL CIRCUITS operate with a 5-volt POWER supply.

Correct OPTION is (b) Multiple-emitter TRANSISTOR

The best I can explain: TTL INPUTS are the EMITTERS of a multiple-emitter transistor.

Correct answer is (b) James L. Buie

The BEST EXPLANATION: TTL was INVENTED in 1961 by James L Buie.

Correct answer is (d) Bipolar junction transistors (BJT) and RESISTORS

The best EXPLANATION: Transistor–transistor logic (TTL) is a class of DIGITAL circuits built from bipolar junction transistors (BJT) and resistors. However, resistors have a small role to play and both logic gating and amplifying functions are PERFORMED by the transistors.

The correct OPTION is (b) The input resister to the TRANSISTOR

Best EXPLANATION: A disadvantage of DTL is the input resistor to the transistor and its presence tends to slow the circuit down. Hence limiting the speed at which the transistor is able to SWITCH states. Thus, the propagation delay increases.

The correct option is (c) An ADDITIONAL transistor and diode may be used

Best explanation: To increase FAN-out of the gate in DTL, an additional transistor and diode may be used. Here, the fan out means the NUMBER of maximum input that a SINGLE gate output can feed.

Right CHOICE is (b) Increased fan in

To explain I WOULD SAY: A MAJOR advantage over the earlier resistor–transistor logic is the increased fan in. Fan-in is the measure of the MAXIMUM number of inputs that a single gate output can accept.

The CORRECT choice is (a) Baker clamp

To explain I would SAY: Another WAY to speed up DTL other than ADDING a small “speed-up” capacitor across intermediate resister is to avoid saturating the switching transistor which can be done with a Baker clamp. The name Baker clamp is given at the name of Richard H. Baker, who DESCRIBED it in his 1956 technical report “Maximum Efficiency Switching Circuits”.

Right option is (a) Small “SPEED-up” capacitor

To elaborate: ONE WAY to speed up DTL is to add a small “speed-up” capacitor across intermediate resister. The capacitor helps to turn off the transistor by removing the stored base charge; the capacitor also helps to turn on the transistor by increasing the INITIAL base DRIVE.

The correct answer is (a) Large

The EXPLANATION is: Propagation delay refers to the TIME taken by the output to change it’s state when the input is altered. When the transistor goes into saturation from all inputs being high charge is STORED in the BASE REGION. When it comes out of saturation (one input goes low) this charge has to be removed and will dominate the propagation time which results as a large propagation delay. Thus, it has small clock frequency.

The correct CHOICE is (B) 3

Easy EXPLANATION: The DTL circuit SHOWN in the picture CONSISTS of three stages: an input diode logic stage, an intermediate level shifting stage and an output common-emitter amplifier stage.

Right answer is (b) TRANSISTOR

Best explanation: The amplifying and switching FUNCTION is performed by a transistor and the diode acts an input network in DTL.

The CORRECT choice is (a) Diode

To EXPLAIN: Diode SERVES as the input network and the switching OPERATION is performed by the transistor.

Correct answer is (c) It uses a minimum NUMBER of TRANSISTORS

Easiest explanation: The primary advantage of RTL technology was that it uses a minimum number of transistors. It consists of registers in large AMOUNT and it RESULTS in as high power dissipation. The resistors act as the input network and the transistors PERFORMS the switching operation.

Right option is (a) 2

To EXPLAIN I WOULD say: The MINIMUM number of transistors can be USED by 2 input AND gate is 2 and maximum up to 3.

Correct choice is (b) Transistor–transistor logic

The best I can explain: Diode–transistor logic (DTL) is a class of digital circuits that is the DIRECT ancestor of transistor–transistor logic. To overcome the SHORTCOMINGS of DTL, TTL CAME into EXISTENCE.

The correct answer is (C) Multi-transistor RTL implementation

Explanation: The limitations of the one transistor RTL NOR gate are overcome by the use of multi transistor RTL. It consists of a set of PARALLEL CONNECTED transistor switches driven by the logic INPUTS.

Right choice is (a) Collector resistor

Easiest EXPLANATION: The role of the collector resistor is to convert the collector current into a VOLTAGE; its resistance is CHOSEN high enough to SATURATE the transistor and low enough to OBTAIN low output resistance. Base Resistor is to provide the necessary biasing to the base of the transistor in order to activate it.

The correct CHOICE is (a) Resistors, BIPOLAR junction TRANSISTORS (BJTs)

The explanation: Resistor–transistor LOGIC (RTL) is a class of DIGITAL circuits built using resistors as the input network and bipolar junction transistors (BJTs) as switching devices.

Right answer is (a) logic 0

The explanation: 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 and in REST CONDITIONS of the input, the output is 0.

The correct CHOICE is (c) High

The best EXPLANATION: All INPUT of NOR as low produces the result as high, whereas, rest all CONDITIONS produce output as low.