ADE Q_Bank

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ANALOG AND DIGITAL ELECTRONICS

ONE MARK QUESTIONS

UNIT -1

1. What is operational Amplifier?Ans: An Operational amplifier is a direct coupled high gain negative feedback amplifier. It

can amplify the signals having the frequency range of 0Hz to 1MHz.

Operational amplifier direct coupling gain- negative feedback amplifier . 0 Hz 1MHz signal- .

2. Draw the symbol of operational Amplifier.Ans:

3. What is the differential Voltage of Ideal Op-Amp?Ans: Differential voltage of ideal Op-Amp is Zero

4. What is the input offset voltage.Ans: This is the input voltage which must be applied between input terminals to obtain

zero output voltage.

Output voltage- zero- Input terminal- input voltage input offset voltage .

5. What is the input offset current.Ans: It is the difference between the two input currents entering the two input terminals of

a balanced operational amplifier.

Balance Op-Amp- Input terminal

current- Input offset current .

6. What are the inputs of Op Amp?Ans: 1. Inverting

2. Non-Inverting


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7. Define input Bias current.Ans: Input bias current is the average of the currents that flow into the input terminals of a

balanced operational amplifier.

Balance Op-Amp- Input terminal-

current- Input bias current .

8. What is open loop voltage gain?Ans: When the Op-Amp is used without any feedback, the differential voltage gain is

known as open loop voltage gain.

Op-Amp- feedback

differential voltage gain .

9. What is virtual ground of an Op-Amp?Ans: When Non-Inverting input of Op-Amp is connected to ground the inverting input is

approximately at ground potential. The inverting terminal is not connected to ground but it

acts like a ground terminal. This is called as virtual ground.

Op-Amp- Non inverting terminal

Inverting terminal- voltage- ground- . I nverting

terminal- ground voltage zero

virtual .

10.What is summing Amplifier?Ans: The output of a summing amplifier is the amplification of sum of input signal

voltages.

Summing amplifier , input- input signal-

voltage- () amplify .

11.Write the voltage gain of inverting Amplifier.Ans: Voltage gain AV=

= -

12.Define Non- Inverting Amplifier.Ans: If the output of an amplifier is the amplified signal of the input without any phase

change is called as Non-Inverting amplifier.


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Amplifier- output input signal- phase change-

Non-Inverting amplifier .

13.What is voltage Follower?Ans: Unity gain amplifier is called as Voltage follower.

14.Define Comparator.Ans:A circuit which is used to compare two analog signals is called comparator.

15.Write the output of an Integrator.Ans: Vo =

+ Vk(0)

Where Vk(0) = Initial output voltageVo = Output voltage

Vi = Input VoltageC = Capacitance in the integrator circuit

R = Resistance in the integrator circuit

16.What are the uses of IC 555?Ans: 1) It is used as astable multivibrator.

2) It is used as monostable multivibrator.

3) It can be used as Schmitt trigger.

17.What is the Astable multivibrator?Ans: Astable multivibrator is a relaxation oscillator used for producing square wave or

rectangular wave signals. It has no stable state; both the states are quasi stable state.

Astable multivibrator relaxation oscillator . Astable

multivibrator stable state . state quasi stable

state.

18.What is MonoStable Multivibrator?Ans: Multivibrator with only one stable state is called as monostable multivibrator.

stable state- multivibrator- monostable multivibrator .

19.How many stable states are there in Astable Multivibrator?Ans: Astable multivibrator is a relaxation oscillator. It has no stable state; both the states

are quasi stable state.


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Astable multivibrator relaxation oscillator . Astable

multivibrator stable state . state quasi stable

state.

20.What is a Schmitt trigger?Ans: Schmitt trigger is a type of multivibrator. It converts slowly varying input signal into

a square or rectangular signal.

Schmitt trigger monostable multivibrator- .

( Frequency ) input signal- square rectangular

signal- .

21.What is Sequence timer?Ans: When more than one monostable multivibrator is connected in cascade sequence then

it is called as sequence timer.

monostable multivibrator

sequence timer .

22.What are the three types of IC voltage regulators?Ans:1. Three terminal Fixed Voltage regulator

2. Variable output voltage regulator

3. Precision Voltage regulator

23.How the positive and negative voltage IC regulators are are specified.Ans: Positive voltage regulator = 78XX

Negative Voltage regulator = 79XX

24.What type of multivibrator is used in sequence timer?Ans: Monostable multivibrator is used in sequence timer

25.What is LM317?Ans: LM317 is series adjustable three terminal positive voltage regulator.

26.What is the output voltage range of LM317?Ans: Output voltage range = 1.2V to 37V


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27. Define Supply voltage rejection ratio (SVRR)Ans: SVRR is defined as the ratio of the change in input offset voltage to the

corresponding change in one power supply voltage, with all remaining power voltages held

constant.

Input offset- power supply- ( powersupply- voltage- ) SVRR .

28.Define CMRR.Ans: CMRR is defined as the ratio of differential voltage gain (Ad) to the common mode

voltage gain (Acm) .

Common Mode Rejection Ratio (CMRR) =

Differential voltage gain (Ad)- commom mode voltage gain- CMRR .

29.Define Slew Rate.Ans: It is defined as the maximum rate of change of output voltage per unit of time. It is

expressed in volts per microseconds.

Slew Rate (SR) =

v/s

output voltage slew rate .

Volts/microsecond unit- .

30.Write down the formula to calculate the frequency of an astable multivibrator.Ans: T=1.1*RC sec

31.Write any two application of comparator.Ans: 1. To convert sine wave into Square wave signal.

2. As Zero Crossing detector.

32.Draw the pin diagram of IC 555.


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UNIT -2

33.What are the different number systems used.Ans: The different number systems in use are Binary, Octal, Hexadecimal, and BCD

(Binary Coded Decimal).

34.What are the weights of Hexadecimal and Decimal numbers?Ans: Hexadecimal = 16

Decimal = 10

35.What are the weights of Octal and Binary numbers?Ans: Binary = 2

Ocrtal = 8

36.What is the value of A+Aand A.A.?Ans: A+A=1

A.A =0

37.State Demorgans Theorem.Ans:F irst Law :The complement of sum of the variables is equal to the product of their

sum.

A+B=A.BSecond Law:The complement of the product of the variables is equal to the sum of

their complements.

A.B=A+B

38.Which gate is called universal logic gate.Ans: NAND and NOR gate is called as universal logic gate.

39.Why the NAND/NOR gate is called universal logic gate?Ans: NAND and NOR gate are called universal logic gates, because we can construct any

other gates by using either only NAND gates or only NOR gates.

Sum of products boolean

visual display Karnaugh map .

40.What is Karnaugh map?


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Ans: A Karnaugh map is a visual display of the fundamental products needed for a sum of

products solution. By using K-Map we can simplify the Boolean expressions in sum of

product form.

Sum of products boolean

visual display Karnaugh map .

41.How many variables are reduced using pair loops?Ans: Pair loops reduces or eliminates one variable and its complement.

42.Draw the symbol and truth table of AND gate.

43.Draw the symbol and truth table of NAND gate.

44.Draw the symbol and truth table of NOR gate.

45.Draw the symbol and truth table of Ex-OR gate.


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46.Draw the symbol and truth table of Ex-NOR gate.

47.State the logic equation for the following gates a) AND b) Ex-NOR c)Ex-OR and d) OR.Ans: OR = A+B

AND = A.B

Ex-OR = AB

Ex-NOR= AB

48.State the distributive law of Boolean algebra.Ans: 1) A.(B+C)=(A.B)+(A.C)

2) (A+B).(C+D)=(A.C)+(B.C)+(A.D)+(B.D)

49.State the Associative law of Boolean algebra.Ans: 1) A+(B+C)=(A+B)+C

2) A.(B.C)=(A.B).C

UNIT 3

50.What is half adder?Ans: A logic circuit which is used for adding two single bit binary numbers is called Half

adder. Here A and B two inputs and S (SUM) and C (CARRY) are the outputs.

binary bit add logic circuit Half adder . A,B , sum ,carry output .

51.What is full Adder?Ans: A logic circuit which is used for adding three single bit binary numbers is called Full

adder. Here A, B and Cin are three inputs and S (SUM) and C (CARRY) are the outputs.


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binary bit add logic circuit Full adder .

A,B,C , sum ,carry output .

52.What is half subtractor?Ans: A logic circuit which is used for subtracting one single bit binary number from

another single bit binary number is called Half Subtractor. Here A and B two inputs and D

(Difference) and Br (Borrow) are the outputs.

binary bit subtract logic circuit Half subtractor

. A,B input, Difference, borrow

output .

53.What is full Subtractor?Ans: It is a three bit binary subtractor, used for performing three bit binary subtraction.Here B is subtracted from A and C is again subtracted from (A-B).

binary bit subtract logic circuit

Full subtarctor . A,B,C , Difference ,borrow

output

54.Mention five different digital technologies.Ans: Different digital technologies are TTL, CMOS, ECL, I2L, DTL, HTL, etc

55.What is parity Bit?Ans: An additional bit added to the data before transmission for error checking is called

Parity bit.

Binary digital error- 0

1 . bit- Parity .

56.Define even parity.Ans: If the total number of one in the data group including the parity bit is even, then it is

called even parity.

Even parity 1-

1 .

57.Define odd parity.


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Ans: If the total number of one in the data group including the parity bit is odd then it is

called even parity.

Odd parity 1-

1 .

58.What is digital Comparator?Ans: A logic circuit is used for comparing(less than, greater than or equal) two bits is

called a Digital comparator.

binary logic circuit- didital comparator

.

59.Define decoder.Ans: It is combinational logic circuit which as N inputs and 2

Noutputs.

60.What is encoder?Ans: It is combinational logic circuit which as 2

Ninputs and N

outputs.

61.Define multiplexer.Ans: Multiplexer means many into one. It has 2

Ninputs and N

control inputs (Address

lines) and only one output.

62.What is demultiplexer?Ans: DeMultiplexer means one into many. It has one inputs and N

control inputs (Addresslines) and 2

Noutput.

63.Define fan in.Ans: The number inputs connected to the gate without the degradation in the voltage levels

is called as fan in.

gate- input- fan in

.

64.Define fan out.Ans: The maximum number of similar logic gates that a gate can drive without any

degradation in voltage levels is called as Fan out.

gate- output , voltage

logic gate- , fan out .


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65.Define propagation delay.Ans: It is defined as the time taken for the output to change after the inputs have changed.

Logic gate- input output

propogation delay .

66.Define Noise Immunity.Ans: The noise immunity of a logic circuit refers to the circuit ability to tolerate noise

without causing changes in the output voltage.

Noise immunity . circuit-

circuit- output

noise immunity .

67.What is the basic gate of TTL logic?Ans: The basic gate of TTL logic is NAND.

68.What is the basic gate of CMOS logic?Ans: The basic gate of CMOS logic is NAND.

69.What is parity generator?Ans: The logic circuit used to generate parity bit for given set of data bits is called parity

generator.

Binary parity bit - circuit parity generator

.

70.What is the difference between half adder and full adder?Sl.NO HALF ADDER FULL ADDER

1 Performs addition of two bit.Performs addition of three bits.

2OR gate is not present in the logic

diagramOR gate is present in the logic diagram.

UNIT -4

71.What is a sequential logic circuit?Ans: A sequential logic circuit is a circuit in which the output depends on the present input

and the previous output (memory).


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Sequential logic circuit- output

input- , output-

.

72.What is flip flop?Ans: Flip flop is a sequential logic circuit which can store one bit of binary as 0 or 1.

73.What are the output conditions that exist in flip flops?Ans: The output conditions that exist in Flip Flops are 1. No Change 2. Set 3. Reset

4. Toggle.

74.Write three types of flip flop.Ans:1. SR Flip Flop 2. JK Flip Flop 3. CSR Flip Flop 4. D Flip Flop.

75.Define the term toggling.Ans: The condition in which the previous output gets complemented is called as toggling.

output- complement

toggle .

76.What is race around?Ans: When J=K=1 in JK flip flop the output will toggle continuously because the new

outputs are feedback to the input gates immediately. Toggling more than once is called

racing or race-around.

J=K=1 clock pulse=1 output

toggle . clock pulse-

toggling .

77.How the race around condition is is avoided in flip flops.Ans: The problem of racing is avoided in flip flops by using edge type clock pulses.

Edge type clock pulses- racing problem- .

78.Which flip flop can be acted as divide by 2 counters?Ans: T Flip Flop.

79.What is a counter?Ans: A counter is a register capable of counting the number of clock pulses arriving at its

input. Count represents the number of clock pulses arrived.


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80.What are the flip flops used in ripple counter.Ans: JK flip flop and T flip flop can be used in ripple counter.

81.What is mod n counter?Ans: A counter which resets at the N

th

clock pulse is called Mod N counter or Divide by

Nth

counter.

counter- output n clock pulse reset divide by n counter mod N counter .

82.How many flip flops are needed for constructing mod 6 counter.Ans: Three Flip flops

83.How many flip flops are needed for constructing Decade counter.Ans: Four Flip Flops

84.Define state diagram.Ans: The diagram which is used to represent the sequence of inputs, present state, Next

state and output is called as state diagram.

State table state diagram sequential logic circuit- input-

, next state-, output- .

85.What is serial in parallel out shift register?Ans: In Serial in Parallel out Shift register the write operation is in serial form and read

operation is in parallel form.

write serial read parallel

.

86.What is D, T, JK and RS flip flop. Give its truth table.


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87.Define Edge triggering.Ans: The process of making flip flop to produce output either at rising edge or falling edge

of the clock pulse is called edge triggering.

88.What is a shift register?Ans: A register is used to store digital information. Shift register Shifts the content of

register towards left or right in serial or parallel form.

89.What are the differences between Synchronous and Assynchronous counter.

Sl.NO. Assynchronous Counters Synchronous Counters

1The output of first flip flop drives the

clock for the next flip-flop.

There is no connection between the

output of first flip flop and input of the

next flip flop.

2All the flip flops are not clocked

simultaneously.

All the flip flops are clocked

simultaneously.

3 Logic circuit is simple Logic circuit is complex

4 Speed is low due to propogation delay No problem due to propogation delay. So


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speeder than Assynchronous counters.

90.What are the different modes of shift register?Ans: Different modes of shift register are 1. Serial in Serial Out (SISO)

2. Serial in Parallel Out (SIPO)

3. Parallel in Serial Out (PISO)

4. Parallel in Parallel Out (PIPO)

UNIT 5

91.What is digital to analog conversion?Ans: The process of converting digital signal into analog signal is called digital to analog

(D/A) conversion. digital signal- ( ) analog signal

.

92.State the output of binary weighted resistor DAC.Ans: Vo= -

[ 2

N-1bN-1+2

N-1bN-1+..2

2b2+2

1b1+2

0b0]

93.State the output of R-2R ladder type DAC.Ans: Vo=[ 2

N-1

bN-1+2

N-1

bN-1+..2

2

b2+2

1

b1+2

0

b0]

94.What is the resolution in DAC?Ans: It is defined as the smallest possible change in output voltage range as a fraction or

percentage of the full scale output range.


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Resolution D/A converter- full scale output range-

.

95.Define accuracy in DAC.Ans: It is the measure of the difference between the actual output voltage and the expected

output voltage.

Accuracy output- analog voltage-

output- analog voltage- .

96.What is settling time in DAC?Ans: It is the time required for the analog output voltage to settle within (1/2) LSB of the

final value after a change in the digital input.

DAC circuit- input- digital signal

analog output signal settling

time

97.What is analog to digital conversion?Ans: The process of converting analog signal into an equivalent digital signal is known as

analog to digital (A/D) conversion.

analog signal- ( ) digital signal

.

98.What is quantization?Ans: It is the process of mapping (dividing) an analog signal into several equivalent

discrete levels (Ranges or Steps).

analog-, signal quantization .

99.Define voltage to frequency conversion?Ans: It converts DC input voltage into a string of pulses, whose repetition rate (frequency)

is proportional to the magnitude of the input voltage.

Voltage to frequency converter input- DC voltage-

pulse- output- .


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100.What is accuracy in ADC?Ans: It is the measure of the difference between the actual output voltage and the expected

output voltage is called accuracy.

circuit- input voltage output-

digital signal, output- digital sgnal accuracy

101. Define conversion time in ADC.Ans: The time interval between the end of the start signal and the end of conversion is

called conversion time.

circuit- input- output

conversion time

102. State the specification of ADC.Ans: The specifications of ADC are 1. Range of input voltage 2. Input impedance

3. Accuracy 4. Conversion time 5. Differential linearity 6. Resolution 7. Drift

103.What are the components used for fabricating memory cell.Ans: 1. Bipolar Metal Oxide Semiconductors(MOS) 2. Complementary Metal Oxide

Semiconductors (CMOS)

104.What is RAM?Ans: RAM stands for Random Access Memory. It is possible to read and write in any

memory location at the same speed.

105.What is ROM?Ans: ROM stands for Read Only Memory. Data stored in it can be read only. It cannot be

modified.

106.What is PROM?Ans: PROM stands for Programmable Read Only Memory.

107.What is EPROM?Ans: EPROM stands for Erasable Programmable Read Only Memory.

108.What is EEPROM?


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Ans: EEPROM stands for Electrically Erasable Programmable Read Only Memory.

109.What is volatile memory?Ans: In this type of memory the information stored will be lost if the if the power is

removed. Eg. RAM

110.How many 8K memory is needed for creating 16K memory?Ans: Two

111.Define static memory.Ans: Static memory uses flip flops for memory cells. Static memory requires clock signals

in addition to extra power supplies.

112.Define dynamic memory.Ans: Dynamic memory stores data as charges on the capacitors.

113.Define static RAM.Ans: Static RAM uses MOS flip flops for memory cells. Static RAM is also known as

SRAM.

114.Define dynamic RAM.Ans: Dynamic RAM stores data as charges on the capacitors. Dynamic RAM is also

known as DRAM.

115.What is SDRAM?Ans:SD RAM means Synchronous Dynamic Random Access Memory.

116.What is DDR RAM?Ans: DDRRAM stands for Double Data Rate Synchronous Dynamic Random Access

Memory.

THREE MARKS

UNIT 1

1. Mention the characteristics of an ideal Op-Amp.


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Ans:a) High input impedance, Ri= (Infinity)

b) Low output impedance, Ro=0

c) High voltage gain, Av= (Infinity)

d) High bandwidth

e) Perfect balance; Vo=0 when V1=V2f) Characteristics do not drift with temperature

2. Write short notes on virtual ground.Ans: In an inverting amplifier the non inverting input is grounded and input signal is

applied to the inverting input terminal through a resistor Ri.

The differential input voltage is ideally zero. Therefore inverting terminal voltage

V1 is approximately at ground potential when there is no input. The inverting terminal is

not directly connected to ground. But it acts like a ground terminal. Therefore the inverting

terminal is said to be at virtual ground.

3. When a non inverting amplifier is used as a voltage follower?Ans: In non-inverting amplifier, the output voltage is given by Vo=

When Rf=0 and Ri=, the output voltage becomes Vo=(1+0)Vi= Vi

The output voltage follows the input voltage.

The modified circuit is shown in the figure given above is called voltage follower.


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4. What are the features of IC regulator using LM 317?i) Adjustable output down to 1.2Vii)

Guaranteed 1.5A output current

iii)Line regulation typically 0.01% / Viv)Load regulation typically 0.1%v) Current limit constant with temperature.vi)Standard 3 lead transistor packagevii)80db ripple rejection ratioviii)Output is short circuit protected

5. Draw the circuit diagram of inverting amplifier using op-amp.

6. Draw summing amplifier using op-amp and note its output voltage.

7. Draw the block diagram Op-Amp.

8. Draw the pin diagram of IC 741 op-amp and mention its pins.


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9. Draw the simple equivalent circuit of op-amp.

10.Draw the circuit diagram of a differentiator.

11.Draw the pin diagram of IC555 and mention each pin.

12.Draw the functional block diagram of IC555.


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13.Draw the connection diagram of Astable multivibrator using IC555.

14.Draw the connection diagram of monostable multivibrator using IC555.


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15.Draw the connection diagram of Schmitt trigger using IC555.

16.Draw the circuit diagram of voltage regulator using LM317.


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UNIT 2

17.State Demorgans Theorem.Ans:F irst Law :The complement of sum of the variables is equal to the product of their

sum.

A+B=A.B

Second Law:The complement of the product of the variables is equal to the sum of

their complements.

A.B=A+B

18.What is positive logic and negative logic?Ans: Positive logic means that 1 stands for the most positive of the two levels. In this

logic, 1= high=True and 0=Low=False.

Negative logic means that 1 stands for the most negative of the two levels. In this logic,

0= high=True and 1=Low=False.

Majority of the digital system uses positive logic. In positive logic system +5V dc

represents logic 1 and logic 0V dc represents logic 0.

19.Problems on k map and conversion.

20.Construct an Ex-OR gate by using only NAND gates.


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21.Construct a NOR gate by using only NAND gates.

22.Construct an NAND gate by using only NOR gates.

23.Construct a AND gate by using only NAND gates.

UNIT 3

24.What are the methods of used for representing signed binary numbers?Ans: The signed binary numbers are represented in three types they are,

1. Sign and Magnitude2. Sign and 1s complement3. Sign and 2s complement

25.Mention the handling precautions of CMOS ICs.


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28.What are the disadvantages of CMOS gate?Ans: Disadvantages

1. Large chip size2. More expensive3.

High output impedance

29.What are the characteristics of CMOS gates?Ans:Characteristics

1. The switching characteristic is very fast2. It does not vary with temperature3. Power dissipation is directly proportional to the operating frequency4. High noise immunity

30.What are the advantages of TTL gates?Ans:Advantages

1. Compatible with other logic circuits2. Low output impedance3. High speed operation4. Good noise Immunity5. Low power dissipation6. High fan out7. Low Cost

31.What are the disadvantages of TTL gates?Ans: Disadvantages

1. TTL ICs generate switching transistors2. Used special techniques for circuit preparation3. Wired output capability is not possible

32.What are the characteristics of TTL gates?Ans:Characteristics

1. Operate reliably over the range from 4.75V to 5.25V2. Operates in ambient temperature range from 0 to 70oC3. One NAND gate requires an average power of 10mW4. Propagation delay range from 7ns to 11 ns


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5. Fan out : It can drive standard TTL inputsUNIT 4

33.What are the difference between sequential logic and combinational logic circuit?Sl.NO. Combinational Circuit Sequential Circuit

1The output always depends on the

combinational inputs

The outputs depend both the present

input variables and past outputs of these

variables

2 Memory unit is not requiredMemory unit is required to store the past

output

3 They are faster Slower than combinational logic circuits

4 Easy to design Comparatively harder to design

34.Write short notes on race around condition.Ans: When J=K=1 in JK flip flop the output will toggle continuously because the new

outputs are feedback to the input gates immediately. This process repeats continuously, till

the clock input goes to low level. Toggling more than once during a clock cycle is called

racing.

At the end of the clock pulse the output is uncertain. This situation is referred to as

race around condition. It is avoided when tp


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Clock pulse- output . race around condition .

clock pulse- edge- trigger flip flop .

35.What is the difference between synchronous counter and asynchronous counter?Sl.NO. Assynchronous Counters Synchronous Counters

1The output of first flip flop drives the

clock for the next flip-flop.

There is no connection between the

output of first flip flop and input of the

next flip flop.

2All the flip flops are not clocked

simultaneously.

All the flip flops are clocked

simultaneously.

3 Logic circuit is simple Logic circuit is complex

4 Speed is low due to propogation delayNo problem due to propogation delay. So

speeder than Assynchronous counters.

36.What are the different types of shift registers? Define them.Ans: Different modes of shift register are

1. Serial in Serial Out (SISO) :- The write operation and read operation are in serialform.

write read serial .

2. Serial in Parallel Out (SIPO) :- In this configuration the write operation is in serialform and read operation is in parallel form.

write serial read parallel

3. Parallel in Serial Out (PISO):- In this configuration the write operation is in parallelform and read operation is in serail form.

write parallel read serial


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4. Parallel in Parallel Out (PIPO) :- The write operation and read operation are inparallel form.

write read parallel .

37.Write short notes on ring counter.Ans: Ring counter is the simplest form of shift register counter. It is basically a circulating

shift register. The logic diagram of a four bit ring counter using D flip flop is shown in fig

below.

The output of the first flip flop (QA) is connected to the input of second flip flop

(QB) is connected to the input of third flip flop, and the output of third flip flop (QC) is

connected to the input of fourth flip flop. The output of fourth flip flop (Last) (QD) is

connected to the first flip flop, which provides feedback connection.

Ring counter shift register counter- .

output () shift register .

flip flop- output (QA) flip flop- input ,

flip flop- output (QB) flip flop- flip flop- input , flip

flop- output (QC) flip flop- input .

feedback


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UNIT 5

38.Explain the terms linearity and settling time in DAC?Ans: Linearity: In a D/A converter, equal increments in the numerical significance of the

digital input should result in the equal increments in the analog output voltage. In an actual

circuit the input-output relationship is not linear. This is due to the errors in resistor values

and voltage across the switches.

D/A converter - linearity input-

digital input- , output-

analog voltage

.

Settling Time: It is the time required for the analog output voltage to settle within (1/2)

LSB of the final value after a change in the digital input.

DAC circuit- input- digital signal

analog output signal settling

time

39.Explain the term accuracy and monotonocity in DAC?Ans:Accuracy: It is the measure of the difference between the actual output voltage and

the expected output voltage.

Accuracy output- analog voltage-

output- analog voltage- .

Montonocity: A D/A converter is said to be monotonic if its output voltage

increases regularly as its binary digital signal is increased from one value to the next value.

Input- digital

output analog signal-

monotonocity


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40.Explain the term quantization?Ans: It is the process of mapping (dividing) an analog signal into several equivalent

discrete levels (Ranges or Steps). That means, it is the process of converting a continous

input values to a discrete output values.

The transfer function of a quantizer is shown below.While the analog input may

have any value from 0 to high, the output can exist only as one of the 8 discrete values

from 0(000) to 7 (111). Hence the transfer function looks like a staircase.

analog-, signal quantization . input signal- signal output- .

41.What are the advantages of semiconductor memory? They are low cost

Semiconductor memories are small in size.

They operate at high speed

They are highly reliable


33/33

It is easy to expand the memory size.

Documents

ADE Q_Bank