Analog Electronics

Inside a 741 op-amp the last functional block is a

For a three-input inverting summing amplifier, $${{ ext{V}}_{{ ext{out}}}} = - frac{{left( {{{ ext{V}}_1} + {{ ext{V}}_2} + {{ ext{V}}_3}}
ight)}}{3},$$ xa0 xa0 what is the relation between R f and R?

In the circuit shown in the given figure, V 0 is given by

Consider the following statements: To draw a.c. equivalent circuit of a transistor, all 1. d.c. sources are shorted 2. a.c. sources are shorted 3. d.c. sources are opened 4. a.c. sources are connected to d.c. sources Which of the above statements is/are correct?

In ideal op-amp the current through the virtual ground is

In the silicon BJT circuit shown below, assume that the emitter area of transistor Q 1 is half that of transistor Q 2 . The value of current I 0 is approximately

A circuit whose output is proportional to the difference between the input signals is considered to be which type of amplifier?

If the base current of a BJT is 250 µA and emitter is 15 mA, then the common base current gain will be

If the circuit shown has to function as a clamping circuit, then which one of the following conditions should be satisfied for the sinusoidal signal of period T?

The voltage divider bias circuit is used in amplifiers quit often because it

The zener diode shown in following figure is temperature compensated and current gain β of transistor is very high. If current through 100 ohm resistor is 55 mA at 25°C, what is the approximate current through it at 65°C

The output time period of a transistorized monostable multivibrator using base resistance R b and coupling capacitor C b for the output transistor is given by

In a BJT, the I c = 30 mA. If β = 100, the base current approximately equals

Negative voltage feedback in amplifiers S1: Improves gain stability S2: Reduces non linear distortion S3: Improves frequency response S4: Increase circuit stability S5: Increase Input Impedance and decrease output impedance

Transformer utilization factor of half wave rectifier is

An output signal of a power amplifier has amplitudes of 2.5 V fundamental, 0.25 V second harmonic and 0.1 V third harmonic. The total percentage harmonic distortion of the signal is

The voltage gain A v = $$frac{{{{ ext{V}}_0}}}{{{{ ext{V}}_{ ext{i}}}}}$$xa0of the JFET amplifier shown in the figure is (Assume C 1 , C 2 and C s to be very large)

The circuit shown above is:

If the bias current in the IC-741 op-amp is I Q = 19 µA and the internal frequency compensation capacitor C 1 = 30 pF, the slew rate of the op-amp will be nearly

A transistor is said to be useful to be configured as an amplifier when its β is

In BJT, DC load line joins

In the circuit of the relaxation oscillator shown in the given figure, what will be the change in the voltage waveform across capacitor, if the voltage V is doubled?

An N-channel JFET, having a pinch-off voltage (V p ) of -5V, shows a trans conductance (g m ) of 1 mA/V when the applied gate-to-source voltage (V GS ) is -3V. Its maximum trans conductance (in mA/V) is

The circuit using a BJT with β = 50 and V BE = 0.7 V is shown in the figure. The base current I B and collector voltage V C are respectively

The use of rectifier filter in a capacitor circuit gives satisfactory performance only when the load

In op-amp based inverting amplifier with a gain of 100 and feedback resistance of 47 kΩ, the op-amp input offset voltage is 6 mV and input bias current is 500 nA. the output offset voltage due to an input offset voltage and an input bias current, are

The Ebers Moll model is applicable to

An amplifier circuit is shown in the given figure: The voltage gain $$left( {frac{{{{ ext{V}}_0}}}{{{{ ext{V}}_{ ext{s}}}}}}
ight)$$xa0is:

A peak detector comprises a capacitor and an ideal diode and an ac source in series. The following is true of the circuit

In the following limiter circuit, an input voltage V i = 10 sin 100 πt is applied. Assume that the diode drop is 0.7 V when it is forward biased. The zener breakdown voltage is 6.8 V The maximum and minimum values of the output voltage respectively are

Which power amplifier conducts from 0° to 180°

For the Schmitt trigger circuit shown in figure, assuming diodes and op-amp are ideal, the value of lower and upper threshold points of voltage transfer characteristics, respectively, are

A small signal voltage amplifier in common emitter configuration was working satisfactorily. Suddenly its emitter bypass capacitor (C E ) got disconnected. Its: 1. Voltage gain will decrease 2. Voltage gain will increase 3. Bandwidth will decrease 4. Bandwidth will increase Which of these statements are correct?

A Schmitt trigger circuit achieves hysteresis by utilizing

Match the following. List-I List-II a. Hartley 1. Low frequency oscillator b. Wien-bridge 2. High frequency oscillator c. Crystal 3. Stable frequency oscillator

Current stability of a CC amplifier can be increased by

Three identical amplifiers with each one having a voltage gain of 50, input resistance of 1 kΩ and output resistance of 250 Ω, are cascaded. The open circuit voltage gain of the combined amplifier is

In a particular biasing circuit, the value of R E is about . . . . . . . .

In the circuit shown below, the switch was connected to position 1 at t < 0 and at t = 0, it is changed to position 2. Assume that the diode has zero voltage drop and a storage time t s . For 0 < t ≤ t s .V R s given by (all in Volts)

A Darlington stage is shown in the figure is, if the trans-conductance Q 1 is g m1 and Q 2 is g m2 , then the overall trans-conductance gm is given by

The input V i to the circuit shown in figure below is a square wave of amplitude ±1 V and frequency 100 Hz. Assuming ideal components, the peak-to-peak amplitude of the output V 0 is:

Which type of negative feedback is used to improve performance of current amplifier?

For 555 astable multivibrator, if C = 0.01 µF, R A = 10 kΩ, R B = 50 kΩ, the frequency and the duty cycle will be nearly.

The hybrid-pi model is used for:

A source follower (using a FET) usually has a voltage gain which is

In the Hybrid-pi model for the BJT small signal analysis, r π denotes

For the circuit shown in figure, the transistor parameters are V BE = 0.7 V , β = 99. If V C is to be set at 7.5 V, the required value (in kΩ) of R B is

Which one of the following is a wide band amplifier?

The 'h' parameter equivalent circuit of a junction transistor is valid for

For feedback amplifier with gain $$frac{{ ext{A}}}{{1 - { ext{T}}}}$$ xa0feedback reduces the internally generated noise by a factor

A BJT has C e = 1 pF. If g m is 50 mA/V, calculate the f T of a common-emitter amplifier.

The current of a certain Si-diode, when measured with a large reverse bias is found to be 10nA. What would be the current be if a forward bias of 2 V is applied? Assume that T = 300° K, η = 2.

What is the output voltage across the 900 ohm load in the circuit given below?

The effect of dc saturation in a rectifier transformer is

The figure shown is a circuit of which one of the following?

Find output voltage V o in the circuit below:

In the circuit shown, it is required that V 0 = V i the values of $$l$$, m, n are respectively. (x represents don't care condition)

In the circuit shown below, for the MOS transistors, µ n C ox = 100 µA/V 2 and the
threshold voltage V T = 1 V. The voltage V x at the source of the upper transistor is

The cut-in voltage V γ and thermal voltage V T for the diode D in figure shown below are 0.498 V and 2 mV, respectively. If the value of resistor R is 20 Ω, the current flowing through the diode is:

The current through the resistor R in the below

What will be the average value of V(t) in the circuit given below

Match List-I (Application of the circuit) with List-II (Circuit Name) and select the correct answer using the options given below the lists: List-I (Application of the circuit) List-II (Circuit Name) a. Divider 1. Astable multivibrator b. Clips input voltage at two predetermined Levels 2. Schmitt trigger c. Square wave generator 3. Bistable multivibrator d. Narrow current pulse generator 4. Blocking oscillator

Roll-off factor is defined as

Match List-I (Models of BJT) with List-II (Applications) and select the correct answer using the options given below the lists: List-I (Models of BJT) List-II (Applications) a. Hybrid model 1. Microwave measurements b. Hybrid pi-model 2. Coupled diode c. S-parameter 3. Low frequency d. Ebers-Moll model 4. High frequency

Thermal runaway will take place if the quiescent point is such that

The relation between β and α is . . . . . . . .

A transistor has h fe = 50, its h fc will be

Which of the following statements is not true?

The dissipation at the collector is zero in the quiescent state and increase with excitation in the case of a

The responsivity of the PIN photodiode shown is 0.9 A/W. To obtain V out of -1 V for an incident optical power of 1 mW, the value of R to be used is

In the circuit shown below assume that diodes and op-amp are ideal. Suppose that V 01 is the output voltage when input voltage is V s = -1.0 V and V 02 is the output voltage when input voltage is V s = +1.0 V, then the value of V 01 + V 02 is

The circuit shown in figure is a

Consider the following circuit using an ideal op-amp. The I-V characteristics of the diode is described by the relation $${ ext{I}} = {{ ext{I}}_0}left( {{{ ext{e}}^{frac{{ ext{V}}}{{{{ ext{V}}_{ ext{T}}}}}}} - 1}
ight)$$ xa0 where V T = 25 mV, I 0 = 1 µA and V is the voltage across the diode (taken as positive for forward bias). For an input voltage V i = -1 V, the output voltage V 0 is

A second-order band-pass active filter can be obtained by cascading a low-pass second-order section having cut-off frequency f OH with a high-pass second-order section having cut-off frequency f OL , provided

In the circuit shown in figure is a finite gain amplifier with a gain of K, a very large input impedance, and a very low output impedance. The input impedance of the feedback amplifier with the feedback impedance Z connected as shown will be

In a log amplifier the input is 'a'. The output will be proportional to

Diodes are used to clip voltages in circuits because they act as:

An n-type MOSFET and an npn BJT are biased so that I C = I D = 1 mA, V GS = 1.3 V and V BE = 0.7 V. Threshold voltage for the MOSFET is 0.8 V and thermal voltage at the ambient temperature is given to be 25 mV. Transconductances of the BJT and the MOSFET are:

The action of JFET in its equivalent circuit can best be represented as a

In a CB amplifier the maximum efficiency could be

In a p + n junction diode under reverse bias, the magnitude of electric field is maximum at

To prevent a DC return between source and load, it is necessary to use

A constant current signal across a parallel RLC circuits gives an output of 1.4v at the signal frequency of 3.89KHZ and 4.1KHZ. At the frequency of 4KHZ, the output voltage will be

If $$alpha $$ = 0.98, $${I_{{ ext{CO}}}} = 6mu { ext{A}}$$ xa0 and $${I_x08eta } = 100mu { ext{A}}$$ xa0 for a transistor, then the value of $${I_{ ext{C}}}$$ will be

Which of the following is not associated with a p-n junction

The cascade amplifier is a multistage configuration of

An npn BJT has g m = 38 mA/v, C µ = 10 -14 F, C π = 4 × 10 -13 F and DC current gain β 0 = 90. For this transistor f T & f β are

Negative feedback in an amplifier

In a Wien bridge oscillator, the positive feedback attenuation is

Which one of the following multivibrators does not required input clock pulse or trigger?

The MOSFET switch in its on-state may be considered equivalent to:

The Zener diode in the regulator circuit shown in the figure has a Zener voltage of 5.8 volts and a Zener knee current of 0.5 mA. The maximum load current drawn from this circuit ensuring proper functioning over the input voltage range between 20 and 30 volts, is

A power transfer used in class A amplifier has zero signal power dissipation of 10 Watts. If the AC power is 4 W. Calculate collector efficiency.

With reference to the negative feedback voltage - series configuration, which of the following statements is/are correct? 1. Bandwidth increases. 2. Non-linear distortion decreases. Select correct answer.

What is the output voltage V 0 of the above circuit?

In figure T 1 , T 2 and T 3 are p-channel MOS transistors, and T 4 , T 5 and T 6 are n-channel MOS transistors. A, B and C are binary signals. The output f(A, B, C) is

OPAMP circuit given below is a . . . . . . . .

For a class-A power amplifier, supply dc voltage is ± 12 V, the quiescent collector current is 72 mA and the load resistance is 100 Ω. If the output voltage across the load is 12 V peak-to-peak, the efficiency of the amplifier is (neglect the loss occurring in the biasing resistors):

As compared to a full wave rectifier using 2 diodes, the four diode bridge rectifier has the dominant advantage of

For a full-wave rectifier with shunt capacitor filter, the peak to peak ripple voltage is (where f = fundamental power line frequency, I DC = DC current)

In a multi-stage RC-coupled amplifier the coupling capacitor.

An amplifier has a D.C. power supply of 15 V and draws a current of 10 mA. It produces an output of 5 V peak across a load resistance of 600 Ω for a signal frequency of 1 kHz. What will be its A.C. power output?

Determine the change in collector current, ∆I C due to change in base emitter voltage V BE from 25°C to 100°C for a Silicon Transistor in Fixed Bias Configuration having β = 100. (Consider following variation in Silicon transistor parameters with temperature-At T = 25°C, V BE = 0.65 V and At T = 100°C. V BE = 0.5 V)

While using a bipolar junction transistor as an amplifier, the collector and emitter terminals got interchanged mistakenly. Assuming that the amplifier is a common emitter amplifier and the biasing is suitably adjusted, the interchange of terminals will results into which one of the following?

BJT is three terminal device which stands for bipolar junction transistor. Which of the following are true about BJT. 1. Base has smallest area to reduce the transit time. 2. collector is provided with the largest area to withstand heat dissipation. 3. BJT is a current controlled device. 4. BJT is a voltage controlled device.

If the op-amp in the figure has an input offset voltage of 5 mV and an open-loop voltage gain of 10,000, then V 0 will be

The feedback topology in the amplifier circuit (the base bias circuit is not shown for simplicity) in the figure is

What is the load current I L in the circuit below?

Consider the circuit shown below. Find the output voltage V 0 for input voltage V i = 5 V. Assume the voltage drop across a conducting diode is 0.7 V.

The circuit in the figure employs positive feedback and is intended to generate sinusoidal oscillation. If at a frequency $${{ ext{f}}_0},{ ext{B}}left( { ext{f}}
ight) = frac{{{{ ext{V}}_{ ext{f}}}left( { ext{f}}
ight)}}{{{{ ext{V}}_0}left( { ext{f}}
ight)}} = frac{1}{6}angle {0^ circ }$$ xa0 xa0 then to sustain oscillation at this frequency

A bleeder resistor is used in a D.C power supply because it

In the following astable multivibrator circuit, which properties of V 0 (t) depend on R 2 ?

In a half-wave rectifier, if an a.c. supply is 60 Hz, then what is the a.c. ripple at output?

Consider an ideal long channel nMOSFET (enhancement-mode) with gate length 10 µm and width 100 µm. The product of electron mobility (µ n ) and oxide capacitance per unit are (C ox ) is µ n C ox = 1 mA/V 2 . The threshold voltage of the transistor is 1 V. For a gate-to-source voltage V GS = [2 - sin(2t)] V and drain-to-source voltage V DS = 1 V (substrate connected to the source), the maximum value of the drain-to-source current is . . . . . . . .

An n-channel depletion MOSFET has following two points on its I D - V GS curve: (i) V GS = 0 at I D = 12 mA and (ii) V GS = -6 volts at Z 0 = ∞ Which of the following Q-points will give the highest transconductance gain for small signals?

A full wave rectifier with a centre tapped transformer supplies dc current of 100 mA to a load resistance of 20Ω. The secondary resistance of transformer is 1Ω. Each diode has a forward resistance of 0.5Ω. What are rms values of signal voltage across each half of the secondary as well as dc power supplied to the load?

Two transistors have the same value of α but different gain bandwidth products. One of them is a germanium transistor and the other is a silicon transistor. Both the transistors have similar geometries and base width. The transistor with lower GB product.

A transistor RC coupled amplifier is designed for a voltage and band gain of 20. But a measurement at a particular frequency shows the gain to be only 14. What is the likely phase shift at this frequency?

The Wien bridge oscillator is

In a CMOS CS amplifier, the active load is obtained by connecting a

Match List-I with List-II and select the correct answer using the options given below the lists: List-I (Oscillator) List-II (Characteristics Features) a. Wien Bridge 1. RF oscillator two inductance and one capacitance on the reactance network. b. Colpitts 2. LC oscillator for radio frequency : three capacitances and one inductance in the reactance network. c. Hartley 3. RC oscillator for audio frequency applications. d. Clapp 4. RF oscillator : two capacitances and one inductance as the reactance network.

Calculate the frequency of following circuit

In figure what is the base current if V BE = 0.7 V?

What will be the period and frequency of oscillation for an astable multivibrator, given the following specifications? R 1 = 1 kΩ R 2 = 5.6 kΩ C 1 = 0.01 µF C 2 = 0.03 µF

The percentage regulation of Half-wave rectifier is

Which one of the following statements is correct? The rise time of an amplifier is

Assume the op-amp in the circuit of figure to be ideal. The value of the output voltage v 0 is

An amplifier circuit has an overall current gain of -100 and an input resistance of 10 kΩ with a load resistance of 1 kΩ. The overall voltage gain of the amplifier is

The low frequency gain of LPF shown is

The bandwidth of a double tuned transformer coupled amplifier can be adjusted by varying the

The amplifier circuit shown below uses a silicon transistor. The capacitors C C and C E can be assumed to be short at signal frequency and the effect of output resistance r 0 can be ignored. If C E is disconnected from the circuit, which one of the following statements is TRUE?

The current gain of bipolar transistor drops at high frequency because of

Most of the linear ICs are bases on two transistor differential amplifiers because of

An amplifier has an open loop gain of 1000±10. Negative feedback is provided such that the gain variation remains within 0.1%. What is the amount of feedback β F ?

For the circuit given below, the voltage V 0 across the op-amp output is:

In phase-shift oscillator, a single RC network introduces a phase change of

The feedback factor β for a voltage shunt feedback amplifier is given by

Which of the following principles is applied while designing the output matching network for a high power Class-C amplifier?

In the given circuit, V be = 0.7 V, V z = 5.3 V, β = 100. V 0 is

A signal of 1 kHz is to be amplified, but the circuit board and wires pick up and store 60 Hz component from a nearby electric line. If this component is 40 dB higher than the desired signal, what filter stop band attenuation is necessary to ensure the signal remains 20 dB above the interferer level?

A Wien bridge oscillator is a

The voltage gain of a common emitter amplifier is:

Decreasing the gain in the op-amp non-inverting amplifier circuit could be achieved by:

Thermal runaway in a transistor biased in the active region is due to 1. heating of the transistor. 2. change in β due to increase in temperature. 3. change in reverse collector saturation current due to rise in temperature. 4. base emitter voltage V BE which decreases with rise in temperature. Which of the above statements is/are correct?

Pulses of definite width can be obtained from irregular shaped pulses:

In an Op-Amp A d = 80dB, CMRR = 40dB, A c in dB

Current gain with feedback A if = . . . . . . . .

An operational amplifier has a slew rate of 100 V/microsecond. For a frequency of 10 MHz, the maximum (peak) value of the sine wave output voltage will be

Which class of amplifier has the lowest collector circuit efficiency

Consider the following statements: Sziklai pair 1. Is also called complementary Darlington 2. Acts like a single p-n-p transistor with a very high current gain 3. Can be used in class B push-pull power amplifier Which of these statements are correct?

In an op-amp, non-inverting terminal is grounded, input is connected to inverting terminal and there is no feedback resistance. The output is

What are the output voltage levels for the given circuit? (Assume Si diode)

A bipolar junction transistor is in saturation region. Given V CC = 10 V, R C = 1 kΩ, h FE = 100 and V CEsat = 0.3 V. What is the collector current in saturation?

The first dominant pole encountered in the frequency response of a compensated op-amp is approximately at

In the Wien bridge oscillator, the 0° phase-shift is met by using lead-lag network and by using.

Among CB, CE and CC configurations of the amplifiers, which is having low voltage gain and high current gain?

The output voltage (V 0 ) of the circuit shown in the given figure is

An amplifier without feedback has a voltage gain of 50, input resistance of 1 kΩ and output resistance of 2.5 kΩ. The input resistance of the current-shunt negative feedback amplifier using the above amplifier with a feedback factor of 0.2 is

The negative feedback in an amplifier leads to which one of the following?

The equivalent dc output voltage of a half wave rectifier is . . . . . . . . the equivalent dc output voltage of a full wave rectifier.

For the circuit given in the figure, consider the following statements: 1. The output V O will consist of a positive and a negative spike if RC << T. 2. The output V O will be similar to V i if RC >> T. 3. The output will have a higher rise time if RC is made progressively smaller than T. Of these statements:

Cascode amplifier when compared with a simple common-emitter amplifier provide which of the following?

In the circuit shown in the given figure, the approximate voltage at the transistor

Which is not considered as a linear voltage regulator?

A Schmitt trigger is a digital circuit that produce

The transistor shunt regulator shown in the figure has a regulated output voltage of 10 V, when the input varies from 20 V to 30 V. The relevant parameters for the zener diode and the transistor are: V Z = 9.5, V BE = 0.5 V, β = 99. Neglect the current through R B . Then the maximum power dissipated in the zener diode (P Z ) and the transistor (P T ) are

The following configuration is an example of positive feedback system:

Barkhausen criterion is related to

When L is doubled and C is halved, the frequency of oscillation is?

If the OP-AMP shown in the figure below is ideal, then the output voltage V out will be equal to

V o for the above op-amp circuit is:

Which of the following is the main application of Zener diode?

Consider the following? 1. Distortion 2. Gain 3. Bias stabilization 4. Sensitivity 5. Frequency response Which of these properties of the Power Amplifier one should concentrate upon while designing a good Power Amplifier circuit?

Cascading amplifier stages to obtain a high gain is best done with . . . . . . . .

An FET is a better chopper than a BJT because it has

For the circuit shown in the figure below, the voltage V 0 is (here D is an ideal diode)

In a class-B push-pull operation, the d.c. power drawn is 28 W. What is the power delivered by the amplifier at the ideal maximum efficiency of power conversion?

An amplifier with mid band gain |A| = 500 has negative feedback |β| = $$frac{1}{{100}}.$$ xa0If upper cut-off without feedback were at 60 kHz, then with feedback it would become

As compared to a BJT amplifier, an amplifier made using a JEET is likely to have

The bandwidth of a Class C amplifier decreases when the

Consider a single stage tuned amplifier having 3 dB bandwidth of 100 kHz. Determine the bandwidth if two such single tuned amplifiers are cascaded:

The amplifier which retains the shape of the input signal at the output are called-

The circuit of the figure is an example of feedback of the following type

In a typical 555 astable multivibrator circuit, if R A = R B = 2.2 kΩ and C = 0.1 µF then the free-running frequency is:

Match List-I with List-II and select the correct answer using the options given below the lists: List-I List-II a. RC coupling 1. Higher voltage gain & impedance matching b. Inductive coupling 2. Ability to amplify dc and low frequency signals c. Transformer coupling 3. Minimum possible non-linear distortion d. Direct coupling 4. Low collector supply voltages can be used

The drain of an N-channel MOSFET is shorted to the gate such that V GS = V DS . The threshold voltage (V T ) of MOSFET is 1 volt. If the drain current (I D ) is 1 mA for V GS = 2 V, then for V GS = 3 V, the drain current I D is-

In the circuit shown in figure below, β for the BJTs is 99. Assuming the thermal voltage to be 50 mV, the input resistance R i is:

When a voltage divider biased amplifier has its Q-point near to the middle of the dc-load line, what is the maximum unclipped peak-to-peak output voltage?

The data sheet for a certain JFET ( Junction Field Effect Transistor) indicates that I DSS (drain to source current with gate shorted) = 15 mA and V GS(off) (Cut-off value of gate to source voltage) = -5V. What is the drain current for V GS = -2V?

The lower cut-off frequency of the transistor stage in the adjoining figure is

The circuit given in the figure is a

A monostable multivibrator is frequently used:

The phase shift oscillator requires

The Class-B push-pull amplifier is an efficient two-transistor circuit, in which the two transistors operate in the following way:

The common-mode voltage gain is . . . . . . . .

Introducing a resistor in the emitter of a common emitter amplifier stabilizes the dc operating point against variation in

g m of MOSFET is controlled by

A 741 OP-AMP has an open loop gain 200,000. The output offset voltage is 2 mV. If the input terminals are shorted, the output voltage is

An amplifier without feedback has a voltage gain of 50, input resistance of 1 kΩ & Output resistance of 2.5 kΩ.The input resistance of the current shunt negative feedback amplifier using the above amplifier with a feedback factor of 0.2 is

The most commonly used amplifier in sample & hold circuits is

An n-channel JFET has $${I_{{ ext{DSS}}}} = 2,{ ext{mA}}$$ xa0 and V p = -4 v. Its transconductance g m = in (mA/V) for an applied gate to source voltage V GS = -2 v is

In a common emitter, unbypassed resister provides

The current gain of a BJT is

The current gain of a bipolar transistor drops at high frequencies because of

Generally, the gain of a transistor amplifier falls at high frequencies due to the

An amplifier using an opamp with slew rate SR=1v/µsec has a gain of 40db.if this amplifier has to faithfully amplify sinusoidal signals from dc to 20 KHz without introducing any slew-rate induced distortion, then the input signal level must not exceed

Voltage Series (feedback also called series-shunt feedback) results in

MOSFET can be used as a

An amplifier using BJT has two identical stages each having a lower cut-off (3 dB) frequency of 64 Hz due to coupling capacitor. The emitter bypass capacitor also provides a lower cut-off (3 dB) frequency due to emitter degeneration alone of 64 Hz. The lower (3 dB) frequency of the overall amplifier is nearly

What would be the output of the following circuit, if a positive going unipolar pulse with an amplitude greater than V ref , is applied at the input?

A high gain OpAmp has R f = 10 5 Ω & R i = 10 3 Ω. The correct statements is:

The V 0 of the op-amp circuit shown in the given figure is

The main advantage in using three op-amp instrumentation amplifier over a single stage op-amp differential amplifier lies in

In the circuit shown in the given figure, R F provides

An n-channel enhancement mode MOSFET is biased at V GS > V TH and V DS > (V GS - V TH ), where V GS is the gate-to-source voltage. V DS is the drain-to-source voltage and V TH is the threshold voltage. Considering channel length modulation effect be significant, the MOSFET behaves as a

For an OPAMP, unity gain frequency is 10 6 if gain is 20, What is the Bandwidth of the op-amp . . . . . . . .

The cross-over distortion in class B push-pull amplifier is eliminated by

The transfer function of a second order low pass filter shown in Figure is

For a bipolar junction transistor, if the current amplification factor and cut-off frequency in the CB mode are α CB and fα CB respectively, then the cut-off frequency in the CE mode is equal to

In the circuit shown below, the silicon npn transistor Q has a very high value of β. The required value of R 2 (in kΩ) to produce I c = 1 mA is

The given circuit represents the amplifier type as:

Consider the common-collector amplifier in the figure (bias circuitry ensures that the transistor operates in forward active region, but has been omitted for simplicity). Let I C be the collector current, V BE be the base-emitter voltage and V T be the thermal voltage. Also, g m and r o are the small-signal trans-conductance and output resistance of the transistor, respectively. Which one of the following conditions ensures a nearly constant small signal voltage gain for a wide range of values of R E ?

Find V O for the given circuit. (Assume ideal diode)

Which of the stages listed below would drive the loudspeaker, in a class D amplifier?

In a digital frequency meter, the Schmitt trigger is used for

Leakage current approximately doubles for every 10°C increase in temperature of a silicon transistor. If a silicon transistor has I CBO = 1000 nA at 30°C, what is its leakage current at 90°C?

In an RC differentiator, the condition for differentiation is

A circuit is shown in the given figure. The largest value of R L that can be used is

A high gain MESFET packaged device of case-to-channel thermal resistance of the device is 4.5°C/Watt provides 8W RF output power taking 20W DC power. What will be the channel temperature of the device if the case temperature of the device maintained at 55°C?

What is the percentage reduction in gain of an amplifier due to introduction of 20 dB of negative feedback?

The rise time of low pass RC Circuit is given by

Transistor in power amplifier is . . . . . . . .

Which one of the following conditions would give V o = 0 in the circuit shown in the figure?

For which of the following conditions, the circuit shown below will function as precision full wave rectifier?

Which one of the following circuits is most suitable as an oscillator at a frequency of 100 Hz.

An amplifier has two identical cascaded stages. Each stage has a bandwidth of 20 kHz. The overall bandwidth shall approximately be equal to

If an op-amp comparator has a gain of 100, 000, an input difference of 0.2 mV above reference, and a supply of ±12 V. The output will be:

An amplifier has a signal input voltage V i of 0.25 V and draws 1 mA from the source. If the amplifier delivers 8 V to a load of 10 mA, the power gain is

For a MOSFET satisfying the relationship V DS < V GS - V TH , where the drain voltage is V DS , the gate voltage is V GS , and the threshold voltage of the transistor is V TH , then the transistor is said to operate in:

To get a peak load voltage of 40 V out of a bridge rectifier. What is the approximate rms value of secondary voltage?

If the inverting input terminal of an operational amplifier is grounded and a sinusoidal voltage waveform is applied at the non-inverting input terminal, the output will be:

In order to increase the bandwidth of tuned amplifiers, one can use: 1. Tuned circuit with inductance having high Q factor 2. Double tuned amplifier with two tuned circuits coupled by mutual inductance 3. Staggered tuned amplifiers in which different tuned circuits which are cascaded are tuned to slightly different frequencies

All transistor in the N output current mirror in the figure are matched with a finite gain β and early voltage V A = ∞. The expression for load current is

For an n-channel MOSFET, if condention parameter (k n ) is 0.249 mA/V 2 , gate to source voltage V GS is 2V IN where V IN = 0.75 V. The current will be

The encapsulation of transistor is necessary for

In deriving ac equivalent circuit for an amplifier circuit we short circuit

Thermal runaway is not possible in FET because as the temperature of FET increases

The direction of induced e.m.f. can be found by

In an iron cored coil the iron core is removed so that the coil becomes an air cored coil. The inductance of the coil will

A crack in the magnetic path of an inductor will result in

Consider the following statements: A clamper circuit 1. adds or subtracts a dc voltage to or from a waveform. 2. does not change the shape of the waveform. 3. amplifies the waveform. Which of the statements give above are correct? Of these statements

Class-B amplifier has less efficiency compared to

In a MOSFET operating in the saturation region, the channel length modulation effect causes

A two stage capacitor coupled CE amplifier has stages having a voltage gain of 100 each. It is known that the gain of each stage drops by 3 dB at lower cutoff frequency. What is the overall gain of the multistage amplifier at lower cutoff frequency?

Input resistance of inverting amplifier as shown in figure with ideal op-amp is:

In an op-amp, if the feedback voltage is reduced by connecting a voltage divider at the output, which of the following will happen? 1. Input impedance increases 2. Output impedance reduces 3. Overall gain increases

The reason for using a precision OPAMP based rectifier diode for detecting weak AM signals is that

Negative feedback amplifier is a . . . . . . . .

In the amplifier circuit shown in the figure, the values of R 1 and R 2 are such that the transistor is operating at V CE = 3 V and I C = 1.5 mA when its β is 150. For a transistor with β of 200, the operating point (V CE , I C ) is

In the break region of clipping circuit, a diode behaves as

One of effect of negative feedback in amplifier is to

Output characteristics of a BJT amplifier is given. Find the minimum collector current required for r 0 = 50 kΩ. (r 0 is output resistance)

An N-Channel JFET has I DSS = 8 mA and V p = -5 V. The minimum value of V DS for pinch-off region and the drain current I DS for a V GS = -2V are.

From measurement of the rise time of the output pulse of an amplifier whose input is a small amplitude square wave, one can estimate the following parameter of the amplifier.

A monolithic metal oxide semiconductor (MOS) non-polarized capacitor which is a parallel plate capacitor with SiO 2 as dielectric. A surface thin film of metal (aluminum) is the top plate. The bottom plate consists of the heavily doped n* region that is formed during emitter diffusion. What is the typical value of
capacitance for an oxide thickness of 500 Å of this MOS capacitor? Take the permittivity of dielectric (ε r ) as 4.

Which of the following holds FALSE for BJTs?

In order to ensure that the output voltage of an op-amp is zero, when both its inputs are grounded

If α = 0.98, I CO = 6 µA and I B = 100 µA for a transistor, then the value of I C will be

The circuit of figure uses an ideal Op-Amp for small positive values of V in , the circuit works as

For a common emitter. BJT configuration with collector terminal resistance R, the slope of the D.C. load line can be given by:

The value of h FE (the hybrid parameters) of a Common-Emitter (CE) connection of a Bipolar Junction Transistor (BJT) is given as 250. What is the value of α dc (ratio of collector current to emitter current), for this BJT?

Consider the following statements regarding an op-amp: 1. All types of negative feedback reduce nonlinear distortion. 2. All types of negative feedback reduce the output offset voltage. 3. Non-inverting (current and voltage) feedback increases the input impedance. 4. Inverting (current and voltage) feedback decreases input impedance. Which of the above statements is/are correct?

For the operational amplifier circuit shown, the output saturation voltages are ±15 V. The upper and lower threshold voltages for the circuit are, respectively,

In the given block diagram, which is the sampling element?

Bootstrap voltage sweep generator uses

Using the incremental low frequency small-signal model of the MOS device, the Norton equivalent resistance of the following circuit is

The approximate O/P Frequency of 555 Oscillator for R A = R B = 2.2 kΩ and C = 2000 pF-

An OPAMP-based comparator drives an LED, with V F = 1.6V, the current through which is regulated by a 1 kΩ resistor and a silicon diode in series. Assume a ±10V DC voltage is applied as ±V CC respectively to the op-amp. Then find out the current through the LED when the comparator output is +10V.

Blocking oscillators are used as

What is the formula of lower cut-off frequency of an RC coupled amplifier?

A common emitter transistor amplifier has a collector load of 10 kΩ. If its h fe = 100 and h ie = 2 kΩ (h re ≈ h oe ≈ 0), the voltage amplification of the amplifier is nearly equal to

When the gate-to-source voltage (V GS ) of a MOSFET with threshold voltage of 400 mV, working in saturation is 900 mV, the drain current is observed to be 1 mA. Neglecting the channel length modulation effect and assuming that the MOSFET is operating at saturation, the drain current for an applied V GS of 1400 mV is

Asource follower using an FET usually has a voltage gain which is

Three identical amplifiers with each one having a voltage gain of 50,input resistance of 1KΩ & output resistance of 250, are cascaded. The open circuit voltage gain of combined amplifier is

A dc power supply has no-load voltage of 30v,and a full-load voltage of 25v at full-load current of 1A.Its output resistance & load regulation ,respectively are

In an OP-amp differentiator

Class AB operation is often used in power large signal) amplifiers in order to

Which of the following amplifier circuit using junction transistor has the best gain?

When a transistor is connected in common emitter mode, it with have

In all base driver amplifiers

The effective channel length of a MOSFET in a saturation decreases with increase in

Which of the following statements is false?

A change in the value of the emitter resistance Re in a differential amplifier

The bandwidth of an RF tuned amplifier is dependent on

Introducing a resistor in the emitter of a common amplifier stabilizes the dc operating point against variations in

The MOSFET switch in its onstate may be considered equivalent to

Most of the linear ICs are based on the two-transistor differential amplifier because of its

The horizontal intercept of dc load line is the same as ideal

A 741-type OP-amp has a gain-bandwidth product of 1MHz. A non-inverting amplifier using this OP-amp & having a voltage gain of 20 db will exhibit -3 db bandwidth of

A differential amplifier is invariably used in the input stage of all OP-amps. This is dome basically to provide the OP-amps with a very high

The early effect in a bipolar junction transistor is caused by

In a transistor leakage current mainly depends on

The op-amp circuit shown in the given figure be used for

Transistors ratings symbols using capital letter and with subscripts also in capital letters denotes

Crest factor for an alternating current source is the ratio of

Each Transistor in Darlington pair (as shown in Fig.) has h fe = 100. Overall h fe of composite transistor neglecting leakage current is,

An amplifier's power level is changed from 8, watts to 16 watts, equivalent dB gain is

In common emitter BJT amplifier, the maximum usable supply voltage is limited by

Which of the following circuits converts any arbitrary waveform into square waveform?

In a hybrid π model, which terminal is NOT accessible?

Calculate the value of I E for a transistor that has α dc = 0.98 and I B = 100 µA.

For an amplifier, which parameter is calculated with V S = 0?

Which one of the following statements regarding slew rate is correct?

The transistor as shown in the circuit is operating in:

By the use of which of the following the PPM can be converted to PWM?

If a common emitter amplifier with an emitter resistance R e has an overall trans-conductance gain of -1 mA/V, a voltage gain of -4 and desensitivity of 50, then the value of the emitter resistance R e would be:

For the transistor amplifier in the given figure, the voltage amplification is approximately.

In the circuit shown below, if R C = 10 kΩ, R L = 10 kΩ, β = 100, input signal voltage is 1 mV r.m.s. The output voltage is:

RC oscillator is basically a-

In an amplifier the increase in gain is 12 dB if the frequency is doubled. What will be the gain if frequency is increased 10 times?

If an amplifier with gain of -1000 and feedback factor of β = -0.1 had a gain change of 20% due to temperature, the change in gain of the feedback amplifier would be

For the junction transistor, which of the following relation is true?

An op-amp having input voltage V i 1 = 150 µV and V i 2 = 140 µV, differential gain A d = 4000 and CMRR = 10 5 . The output voltage of op-amp will be

The load impedance Z L of common emitter amplifier has R and L in series. The phase difference between output and input will be

Match List-I with List-II and select the correct answer using the options given below the lists: List-I (Name of the circuit) List-II (Characteristics of the circuit) a. Darlington Amplifier 1. A circuit using pnp and npn transistors used in power amplifier. b. Common base Amplifier 2. A Common-source Amplifier driving a common gate amplifier. c. Complementary Symmetry Amplifier 3. A Circuit with overall voltage gain close to 1 and very large input impedance. d. Cascode Amplifier 4. A Circuit with low input impedance mainly used in high frequency applications.

The overall bandwidth of two identical voltage amplifiers connected in cascade will be:

The voltage transfer characteristics as shown in the figure will relate to a 1. Voltage regulator 2. Half-wave rectifier 3. Full-wave rectifier Which of the above is/are correct?

A 5 mV, 1 kHz sinusoidal signal is applied to the input of an op-amp integrator for which R = 100 kΩ and C = 1 µF. the output voltage is:

The function of the diode D in the timer circuit shown below is to

An op-amp is used as a zero-crossing detector. If the maximum output voltage is ±15 Volt p-p and the slew rate is 10 V/µsec, then the maximum frequency will be

A voltage V G is applied across a MOS capacitor with metal gate and p-type silicon substrate at T = 300 K. The inversion carrier density (in number of carriers per unit area) for V G = 0.8 V is 2 × 10 11 cm -2 . For V G = 1.3 V, the inversion carrier density is 4 × 10 11 cm -2 . What is the value of the inversion carrier density for V G = 1.8 V?

For an Op-Amp phase shift oscillation, the frequency of oscillations is

An astable multivibrator has . . . . . . . .

For a voltage follower circuit using an op-amp, which of the following is true?

In half wave rectifier, if V i to the diode is 20 sin (ωt), V dc is

What is the value of R s required to self bias N-channel JFET with V p = -10 V, I DSS = 40 mA and V GSQ = -5 V?

An amplifier has an input power of 2 microwatts. The power gain of the amplifier is 60 dB. The output power will be

The drain gate capacitance of a junction FET is 2 pF. Assuming a common source voltage gain of 20. What is the input capacitance due to Miller effect?

The ripple frequency in a full-wave rectifier is

In JFET, dynamic drain resistance r d is of the order of

The inverting op-amp shown in the figure has an open-loop gain of 100. The closed-loop gain $$frac{{{{ ext{V}}_0}}}{{{{ ext{V}}_{ ext{s}}}}}$$ is

For a full wave rectifier, with sinusoidal input and inductor as filter, ripple factor for maximum load current and minimum load current conditions are respectively

If C 1 = 200 pF, C 2 = 50 pF in Colpitts oscillator and frequency is 1 MHz, then what is the value of inductance required?

The circuit shown in the figure is a

In the circuit shown in the figure, if R L = R C = 1 kΩ, then the value of V 0 will be

Consider an n-channel MOSFET with parameters K n = 0.25 mA/V 2 , V TN = 1 V, λ = 0, C gd = 0.04 pF and C gs = 0.2 pF If the transistor is biased at V GS = 3 V, the unity gain bandwidth of an FET will be

In the circuit shown below what is the output voltage (V out ) if a silicon transistor Q and an ideal op-amp are used?

Consider a 565 PLL with R T = 10 kΩ and C T = 0.01 µF. what is the output frequency of the VCO?

The op-amp circuit shown in the figure is a filter. The type of filter and its cut-off frequency are respectively

In differential-mode, . . . . . . . .

In a practical oscillator circuit, which one of the following limits the amplitude of the oscillations?

Quartz crystal is mostly used in crystal oscillator because

A microphone is connected between the base and the ground of a BJT. A 1 kΩ resistance is connected between the collector V CC . If I s = 6 × 10 -16 A and the peak value of the microphone signal is 20 mV, what is the peak value of the output signal?

Consider the oscillator circuit shown in the figure. The function of the network (shown in dotted lines) consisting of the 100 kΩ resistor in series with the two diodes connected back-to-back is to:

Reverse saturation current in the collector region of a transistor

Which of the following can be magnified by magnetic amplifiers

An ideal value of input resistance of trans resistance amplifier is.

The efficiency of a Class - B amplifier for a supply of V CC = 24 V and peak output voltages V L (P) = 22 V is

A multistage amplifier employs five stages each of which has a power gain of 30? The total gain of the amplifier in dB is . . . . . . . (log 10 30 = 1.477)

Which of the following indicates 2 nd harmonic distortion in power amplifier?

Consider the following statements: Monolithic regulators can be used to 1. Realize a constant voltage regulator. 2. Realize a constant current regulator. 3. Introduce flexibility in setting output voltage level. Of these statements

The r.m.s. value of half wave rectified current is 50A. Its r.m.s. value for full wave rectification would be

How many stages are involved in bipolar op-amp?

Consider the above circuit, for V i = V m sinωt, the output voltage V 0 for R L → ∞ will be:

In the base biased transistor circuit, the junction temperature may vary from 25°C to 75°C. If β increase from 100 to 150 with raising temperature, percentage change in V CE point will be

The range of frequency generated by VHF oscillator is-

An npn BJT has g m = 38 mA/V, C µ = 10 -14 F, C π = 4 × 10 -13 F, and DC current gain β 0 = 90. For this transistor f T and f β are

In the figure, assume that the forward voltage drops of the PN diode D 1 and Schottky diode D 2 are 0.7 V and 0.3 V, respectively. If ON denotes conducting state of the diode and OFF denotes non-conducting state of the diode, then in the circuit,

The large signal bandwidth of an op-amp is limited by

In a transistor circuit I B remains constant but β increases

Biasing is used in transistor amplifiers to 1. Stabilize the operating point against temperature variations. 2. Place the operating point in the linear region of the characteristics. 3. Make α, β and I CO of the transistor independent of temperature variations. 4. Reduce distortion and increases dynamic range.

In the circuit shown in the figure, if e 1 = 2 V, e 2 = 5 V, e 3 = 1 V and E = 2 V, then which one of the diodes will be conducting and what will be the e 0 ?

Consider the following statements regarding the circuit given in the figure, where the output voltage is constant
1. V in > the Voltage at which the Zener breaks down. 2. I L < the difference between I and I z the current at which the Zener breaks down. 3. R s < the Zener normal resistance. Of these statements

Consider an inverting amplifier with a feedback resistor R 2 = 10 kΩ and an op-amp with parameters
A oL = 10 5 and R i = 10 kΩ. Assuming the output resistance R 0 of the op-amp is negligible, the closed-loop input resistance at the inverting terminal of an inverting amplifier will be nearly:

What is the Q-point for a fixed-bias transistor with I B = 75 µA
β DC = 100, V CC = 20 V, R C = 1.5 kΩ