Description : The logic 0 level of a CMOS logic device is approximately (A) 1.2 volts (B) 0.4 volts (C) 5 volts (D) 0 volts
Last Answer : Ans: D CMOS logic low level is 0 volts approx.
Description : In digital ICs, Schottky transistors are preferred over normal transistors because of their (A) Lower Propagation delay. (B) Higher Propagation delay. (C) Lower Power dissipation. (D) Higher Power dissipation.
Last Answer : Ans: A Lower propagation delay as shottky transistors reduce the storage time delay by preventing the transistor from going deep into saturation.
Description : Which TTL logic gate is used for wired ANDing (A) Open collector output (B) Totem Pole (C) Tri state output (D) ECL gates
Last Answer : Ans: A Open collector output.
Description : Logic state 0 in positive logic corresponds to 1. zero voltage 2. positive voltage 3.higher voltage level 4. lower voltage level
Last Answer : Logic state 0 in positive logic corresponds to lower voltage level
Description : Define combinational logic
Last Answer : When logic gates are connected together to produce a specified output for certain specified combinations of input variables, with no storage involved, the resulting circuit is called combinational logic.
Description : A full adder logic circuit will have (A) Two inputs and one output. (B) Three inputs and three outputs. (C) Two inputs and two outputs. (D) Three inputs and two outputs.
Last Answer : Ans: D A full adder circuit will add two bits and it will also accounts the carry input generated in the previous stage. Thus three inputs and two outputs (Sum and Carry) are there.
Description : Karnaugh map is used for the purpose of (A) Reducing the electronic circuits used. (B) To map the given Boolean logic function. (C) To minimize the terms in a Boolean expression. (D) To maximize the terms of a given a Boolean expression.
Last Answer : (C) To minimize the terms in a Boolean expression.
Description : A universal logic gate is one, which can be used to generate any logic function. Which of the following is a universal logic gate? (A) OR (B) AND (C) XOR (D) NAND
Last Answer : Ans: D NAND can generate any logic function.
Description : Which of the following is the fastest logic? (A) ECL (B) TTL (C) CMOS (D) LSI
Last Answer : (A) ECL
Description : The digital logic family which has the lowest propagation delay time is (A) ECL (B) TTL (C) CMOS (D) PMOS
Last Answer : Ans: A The digital logic family which has the lowest propagation delay time is ECL (Lowest propagation delay time is possible in ECL because the transistors are used in difference amplifier configuration, in which they are never driven into saturation and thereby the storage time is eliminated).
Description : Which of the following is the fastest logic (A) TTL (B) ECL (C) CMOS (D) LSI
Last Answer : Ans: B ECL is the fastest logic family of all logic families. (High speeds are possible in ECL because the transistors are used in difference amplifier configuration, in which they are never driven into saturation and thereby the storage time is eliminated.
Description : The output of a logic gate is 1 when all its inputs are at logic 0. the gate is either (A) a NAND or an EX-OR (B) an OR or an EX-NOR (C) an AND or an EX-OR (D) a NOR or an EX-NOR
Last Answer : (D) a NOR or an EX-NOR
Description : The digital logic family which has minimum power dissipation is (A) TTL (B) RTL (C) DTL (D) CMOS
Last Answer : (D) CMOS The digital logic family which has minimum power dissipation is CMOS. (CMOS being an unipolar logic family, occupy a very small fraction of silicon Chip area)
Description : Any number with an exponent of one is equal to 128) A) two. B) itself. C) zero. D) on
Last Answer : B) itself.
Description : Any number with an exponent of zero is equal to 2) A) itself. B) ten. C) zero. D) one.
Last Answer : D) one.
Description : When signed numbers are used in binary arithmetic, then which one of the following notations would have unique representation for zero. (A) Sign-magnitude. (B) 1’s complement. (C) 2’s complement. (D) 9’s complement.
Last Answer : (A) Sign-magnitude.
Description : In successive-approximation A/D converter, offset voltage equal to 1/2 LSB is added to the D/A converter's output. This is done to (A) Improve the speed of operation. (B) Reduce the maximum ... Increase the number of bits at the output. (D) Increase the range of input voltage that can be converted
Last Answer : (B) Reduce the maximum quantization error.
Description : A 4-bit synchronous counter uses flip-flops with propagation delay times of 15 ns each. The maximum possible time required for change of state will be (A) 15 ns. (B) 30 ns. (C) 45 ns. (D) 60 ns.
Last Answer : Ans: A 15 ns because in synchronous counter all the flip-flops change state at the same time.
Description : How many different symbols are used in the octal number system? 108) A) ten B) two C) seven D) eight
Last Answer : D) eight
Description : The base of the octal system is 71) A) eight. B) two. C) ten. D) seven.
Last Answer : A) eight.
Description : What numeric symbols are used in the binary number system? 58) A) 0 through 8 B) 0, 1, 2 C) 1, 2 D) 0, 1
Last Answer : D) 0, 1
Description : How many unique numeric symbols are used in the decimal number system? 47) A) unlimited B) nine C) one D) ten
Last Answer : D) ten
Description : How many symbols are used in the hexadecimal number system? 15) A) sixteen B) six C) ten D) twelve
Last Answer : A) sixteen
Description : A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an ... the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating
Last Answer : Answer: B
Description : Define Asynchronous sequential circuit?
Last Answer : In asynchronous sequential circuits change in input signals can affect memory element at any instant of time.
Description : Define synchronous sequential circuit
Last Answer : In synchronous sequential circuits, signals can affect the memory elements only at discrete instant of time.
Description : What are the different types of shift type?
Last Answer : There are five types. They are, Serial In Serial Out Shift Register Serial In Parallel Out Shift Register Parallel In Serial Out Shift Register Parallel In Parallel Out Shift Register Bidirectional Shift Register
Description : Define shift registers.
Last Answer : The binary information in a register can be moved from stage to stage within the register or into or out of the register upon application of clock ... arithmetic and logic operations used in microprocessors. This gives rise to group of registers called shift registers.
Description : Define registers.
Last Answer : A register is a group of flip-flops flip-flop can store one bit information. So an n-bit register has a group of n flip-flops and is capable of storing any binary information/number containing n-bits.
Description : What is a master-slave flip-flop?
Last Answer : A master-slave flip-flop consists of two flip-flops where one circuit serves as a master and the other as a slave.
Description : What is edge-triggered flip-flop?
Last Answer : The problem of race around condition can solved by edge triggering flip flop. The term edge triggering means that the flip-flop changes state either at the positive ... negative edge of the clock pulse and it is sensitive to its inputs only at this transition of the clock.
Description : Define race around condition.
Last Answer : In JK flip-flop output is fed back to the input. Therefore change in the output results change in the input. Due to this in the positive half of the clock pulse if both J and K are high then output toggles continuously. This condition iscalled ‘race around condition’.
Description : What is the operation of T flip-flop?
Last Answer : T flip-flop is also known as Toggle flip-flop. • When T=0 there is no change in the output. • When T=1 the output switch to the complement state (ie) the output toggles.
Description : What is the operation of JK flip-flop?
Last Answer : When K input is low and J input is high the Q output of flip-flop is set. When K input is high and J input is low the Q output of flip-flop is reset. When both the inputs ... are high it is possible to set or reset the flip-flop (ie) the output toggle on the next positive clock edge.
Description : What is the operation of D flip-flop?
Last Answer : In D flip-flop during the occurrence of clock pulse if D=1, the output Q is set and if D=0, the output is reset.
Description : What are the different types of flip-flop?
Last Answer : There are various types of flip flops. Some of them are mentioned below they are, RS flip-flop SR flip-flop D flip-flop JK flip-flop T flip-flop
Description : Define Flip flop.
Last Answer : The basic unit for storage is flip flop. A flip-flop maintains its output state either at 1 or 0 until directed by an input signal to change its state.
Description : What are the classification of sequential circuits?
Last Answer : The sequential circuits are classified on the basis of timing of their signals into two types. They are, 1)Synchronous sequential circuit. 2)Asynchronous sequential circuit.
Description : What do you mean by comparator
Last Answer : A comparator is a special combinational circuit designed primarily to compare the relative magnitude of two binary numbers.
Description : Define multiplexer
Last Answer : Multiplexer is a digital switch. If allows digital information from several sources to be routed onto a single output line.
Description : What is priority Encoder?
Last Answer : A priority encoder is an encoder circuit that includes the priority function. In priority encoder, if 2 or more inputs are equal to 1 at the same time, the input having the highest priority will take precedence.
Description : Define Encoder?
Last Answer : An encoder has 2n input lines and n output lines. In encoder the output lines generate the binary code corresponding to the input value.
Description : What is binary decoder?
Last Answer : A decoder is a combinational circuit that converts binary information from n input lines to a maximum of 2n out puts lines.
Description : Define Decoder
Last Answer : A decoder is a multiple - input multiple output logic circuit that converts coded inputs into coded outputs where the input and output codes are different.
Description : Define Half adder and full adder
Last Answer : The logic circuit that performs the addition of two bits is a half adder. The circuit that performs the addition of three bits is a full adder.
Description : Convert the decimal number 3.375 to binary. 132) A) 0101.1100 B) 0011.1010 C) 0011.0011 D) 0011.01
Last Answer : D) 0011.01
Description : Convert binary 1001 to octal. 131) A) 1018 B) 98 C) 108 D) 118
Last Answer : D) 118
Description : Convert decimal 19 to octal. 130) A) 278 B) 218 C) 238 D) 178
Last Answer : C) 238
Description : The hexadecimal equivalent of decimal 88 is ________. 129) A) 6816 B) 5816 C) 5116 D) 551
Last Answer : B) 5816
Description : What is the decimal value of 20? 127) A) 2 B) 0 C) 1 D) 3
Last Answer : C) 1