GATE ECE 2017 PYQ

In the figure shown, the npn transistor acts as a switch For the input as shown in the figure, the transistor switches between the cut-off and saturation regions of operation, when T is large. Assume

In the circuit shown, transistors and are biased at a collector current of 2.6mA.Assuming that transistor current gains are sufficiently large to assume collector current equal to emitter current and

In the voltage reference circuit shown in the figure, the op-amp is ideal and the transistors are identical in all respects and have infinitely large values of common-emitter current the relation , wh

The output of the diode circuit shown in the figure is connected to an averaging DC voltmeter. The reading on the DC voltmeter in Volts, neglecting the voltage drop across the diode, is ____________.

Consider the circuit shown in the figure. Assume base-to- emitter voltage =0.8 V and common base current gain of the transistor is unity. The value of the collector- to - emitter voltage (in volt) is

For the circuit shown, assume that the NMOS transistor is in saturation. Its threshold voltage and its transconductance parameter . Neglect channel length modulation and body bias effects. Under these

The Miller effect in the context of a Common Emitter amplifier explains

Assuming that transistors and are identical and have a threshold voltage of 1V, the state of transistors and are respectively.

The amplifier circuit shown in the figure is implemented using a compensated operational amplifier (op-amp), and has an open-loop voltage gain, and an open-loop cut-off frequency The voltage gain of t

An n-channel enhancement mode MOSFET is biased at , where is the gate-to-source voltage, is the drain-to-source voltage and is the threshold voltage. Considering channel length modulation effect to be

In the figure, D1 is a real silicon pn junction diode with a drop of 0.7V under forward bias condition and D2 is a zener diode with breakdown voltage of -6.8 V. The input [latex ]V_{in}(t)[/latex] is

For the DC analysis of the Common-Emitter amplifier shown, neglect the base current and assume that the emitter and collector current are equal. Given that , and the BJT output resistance is practical

A good transconductance amplifier should have

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

A sinusoidal message signal is converted to a PCM signal using a uniform quantizer. The required signal-to-quantization noise ratio (SQNR) at the output of the quantizer is 40dB. The minimum number of

In a digital communication system, the overall pulse shape p(t) at the receiver before the sampler has the Fourier transform P(f). If the symbols are transmitted at the rate of 2000 symbols per second

In binary frequency shift keying (FSK), the given signal waveform are , and , Where T is the bit-duration interval and t is in seconds. Both and are zero outside the interval . With a matched filter (

Let be independent random variables. has mean 0 and variance 1, while has mean 1 and variance 4. The mutual information between and in bits is

Which one of the following graphs shows the Shannon capacity (channel capacity) in bits of a memory less binary symmetric channel with crossover probability P?

Consider the random process X(t)=U+Vt, where U is a zero-mean Gaussian random variable and V is a random variable uniformly distributed between 0 and 2. Assume that U and V are statistically independe

Consider a binary memory less channel characterized by the transition probability diagram shown in the figure. The channel is

Let X(t) be a wide sense stationary random process with the power spectral density as shown in Figure (a), where f is in Hertz (Hz). The random process X(t) is input to an ideal low pass filter with f

Which one of the following statements about differential pulse code modulation (DPCM) is true?

The un-modulated carrier power in an AM transmitter is 5kW. This carrier is modulated by a sinusoidal modulating signal. The maximum percentage of modulation is 50%. If it is reduced to 40%, then the

A modulating signal given By )V is fed to a phase modulator with phase deviation constant =0.5rad/V. If the carrier frequency is 20 kHz, the instantaneous frequency (in kHz) at t = 0.5 ms is _________

Which of the following statements is incorrect?

A unity feedback control system is characterized by the open-loop transfer function The Nyquist path and the corresponding Nyquist plot of G(s) are shown in the figures below. If , then the number of

A unity feedback control system is characterized by the open-loop transfer function The value of k for which the system oscillates at 2 rad/s is ________.

A linear time invariant (LTI) system with the transfer function is connected in unity feedback configuration as shown in the figure. For the closed loop system shown, the root locus for intersects the

For the system shown in the figure, Y(s)/X(s)= __________.

Consider the state space realization , with the initial condition where u(t) denotes the unit step function. The value of is _______.

Consider a stable system with transfer function where and are real valued constants. The slope of the Bode log magnitude curve of G(s) converges to -60 dB/decade as . A possible pair of values for p a

Which one of the following options correctly describes the locations of the roots of the equation on the complex plane?

Which of the following can be pole-zero configuration of a phase-lag controller (lag compensator)?

The open loop transfer function G(s)= Where p is an integer, is connected in unity feedback configuration as shown in figure. Given that the steady state error is zero for unit step input and is 6 for

The Nyquist plot of the transfer function does not encircle the point (1+j0) for K=10 but does encircle the point (-1+j0) for K=100. Then the closed loop system (having unity gain feedback) is

A second - order LTI system is described by the following state equations, Where and are the two state variables and r(t) denotes the input. The output . The system is.

Figure I shows a 4-bits ripple carry adder realized using full adders and Figure II shows the circuit of a full-adder (FA). The propagation delay of the XOR, AND and OR gates in Figure II are 20 ns, 1

A programmable logic array (PLA) is shown in the figure. The Boolean function F implemented is

A 4-bit shift register circuit configured for right-shift operation, i.e, , as shown. If the present state of the shift register is ABCD = 1101, the number of clock cycles required to reach the state

In the latch circuit shown, the NAND gates have non-zero, but unequal propagation delays. The present input condition is: P = Q = '0'. If the input condition is changed simultaneously to P = Q = '1',

A finite state machine (FSM) is implemented using the D flip-flops A and B, and logic gates, as shown in the figure below. The four possible states of the FSM are =00,01,10 and 11. Assume that is held

In a DRAM,

The state diagram of a finite state machine (FSM) designed to detect an overlapping sequence of three bits is shown in the figure. The FSM has an input 'In' and an output 'Out'. The initial state of t

Which one of the following gives the simplified sum of products expression for the Boolean function , where , are minterms corresponding to the inputs A, B and C with A as the MSB and C as the LSB?

Consider the circuit shown in the figure. The Boolean expression F implemented by the circuit is

Consider the D-Latch shown in the figure, which is transparent when its clock input CK is high and has zero propagation delay. In the figure, the clock signal CLK1 has a 50% duty cycle and CLK2 is a o

For the circuit shown in the figure, P and Q are the inputs and Y is the output. The logic implemented by the circuit is

An optical fiber is kept along the direction. The refractive indices for the electric fields along and directions in the fiber are =1.5000 and =1.5001, respectively ( due to the imperfection in the fi

An electron ( ) is moving in free space with velocity m/s towards a stationary electron ( ) far away. The closest distance that this moving electron gets to the stationary electron before the repulsiv

Two conducting spheres S1 and S2 of radii a and b (b>a) respectively, are placed far apart and connected by a long, thin conducting wire, as shown in the figure. For some charge placed on this structu

A two - wire transmission line terminates in a television set. The VSWR measured on the line is 5.8. The percentage of power that is reflected from the television set is ______________

The voltage of an electromagnetic wave propagating in a coaxial cable with uniform characteristic impedance is volts, Where is the distance along the length of the cable in meters. is the complex prop

The expression for an electric field in free space is , where x, y, z represent the spatial coordinates, t represents time, and , k are constants. This electric field

The permittivity of water at optical frequencies is 1.75 . It is found that an isotropic light source at a distance d under water forms an illuminated circular area of radius 5m, as shown in the figur

Standard air-filled rectangular waveguides of dimensions a = 2.29 cm and b= 1.02 cm are designed for radar applications. It is desired that these waveguides operate only in the dominatnt mode but not

As shown, two Silicon (Si) abrupt p-n junction diodes are fabricated with uniform donor doping concentration of and in the n-regions of the diodes, and uniform acceptor doping concentration of and in

An Silicon device is fabricated with uniform and non-degenerate donor doping concentrations of and corresponding to the and n regions respectively. At the operational temperature T, assume complete im

A MOS capacitor is fabricated on p-type Si (silicon) where the metal work function is 4.1 eV and electron affinity of Si is 4.0 eV. =0.9 eV, where and are the conduction band minimum and the Fermi ene

For a particular intensity of incident light on a silicon pn junction solar cell, the photocurrent density ( ) is 2.5 mA/ and the open-circuit voltage ( ) is 0.451 V. consider thermal voltage ( ) to b

Two n-channel MOSFETs, T1 and T2, are identical in all respects except that the width of T2 is double that of T1. Both the transistors are biased in the saturation region of operation, but the gate ov

Consider an n-channel MOSFET having width W, length L, electron mobility in the channel and oxide capacitance per unit area . If gate-to-source voltage =0.7V, drain-tosource voltage ,threshold voltage

For a narrow base PNP BJT, the excess minority carrier concentration ( for emitter, for base. for collector) normalized to equilibrium minority carrier concentration ( for emmiter, for base, for colle

As shown a uniformly doped Silicon (Si) bar of length L = 0.1 m with a donor concentration is illuminated at x = 0 such that electron and hole pairs are generated at the rate of , where . Hole lifetim

The dependence of drift velocity of electrons on electric field in a semiconductor is shown below. The semiconductor has a uniform electron concentration of and electronic charge . If a bias of 5V is

An abrupt pn junction (located at x = 0) is uniformly doped on both p and n sides. The width of the depletion region is W and the electric field variation in the x-direction is E(x). Which of the foll

An npn bipolar junction transistor (BJT) is operating in the active region. If the reverse bias across the base - collector junction is increased, then

A bar of Gallium Arsenide (GaAs) is doped with Silicon such that the Silicon atoms occupy Gallium and Arsenic sites in the GaAs crystal. Which one of the following statement is true?

The clock frequency of an 8085 microprocessor is 5 MHz. If the time required to execute an instruction is 1.4 , then the number of T-states needed for executing the instruction is

The following FIVE instructions were executed on an 8085 microprocessor. MVI A, 33H MVI B, 78H ADD B CMA ANI 32H The Accumulator value immediately after the execution of the fifth instruction is

Consider the circuit shown in the figure. The Thevenin equivalent resistance (in ) across P - Q is _________.

The switch in the circuit, shown in the figure, was open for a long time and is closed at t = 0. The current i(t) (in ampere) at t = 0.5 seconds is ________

The figure shows an RLC circuit exited by the sinusoidal voltage volts, where t is in seconds. The ratio is _________.

In the circuit shown, the positive angular frequency (in radians per second) at which magnitude of the phase difference between the voltages equals radians, is

In the circuit shown, V is a sinusoidal voltage source. The current I is in phase with voltage V. The ratio is

A connection is made consisting of resistance A in series with a parallel combination of resistances B and C. Three resistors of value 10 , 5 , 2 are provided. Consider all possible permutations of th

In the circuit shown, the voltage is described by: where t is in seconds. The time (in seconds) at which the current I in the circuit will reach the value 2 Amperes is ___________.

A periodic signal x(t) has a trigonometric Fourier series expansion If , we can conclude that

Consider the parallel combination of two LTI systems shown in the figure. The impulse responses of the systems are If the input x(t) is a unit step signal, then the energy of y(t) is ____________.

Let x(t) be a continuous time periodic signal with fundamental period T = 1 seconds. Let be the complex Fourier series coefficients of x(t), where k is integer valued. Consider the following statement

An LTI system with unit sample response h[n]= is a

Consider the following statements for continuous-time linear time invariant (LTI) systems. I. There is no bounded input bounded output (BIBO) stable system with a pole in the righthalf of the complex

Consider an LTI system with magnitude response And phase response Arg {H(f)}=-2f If the input to the system is Then the average power of the output signal y(t) is _________.

The input and the output of a continuous-time system are related as . The system is

Let h[n] be the impulse response of a discrete-time linear time invariant (LTI) filter. The impulse response is given by for Let be the discrete-time Fourier system transform (DTFT) of h[n], where is

Consider a single input single output discrete-time system with x[n] as input and y[n] as output, where the two are related as Which one of the following statements is true about the system?

The signal , where t is in seconds is sampled at a rate of 9000 samples per second. The sampled signal is the input to an ideal low pass filter with frequency response H(f) as follows : What is the nu

The transfer function of a causal LTI system is H(s) = 1/s. If the input to the system is , where u(t) is a unit step function, the system output y(t) as is______.

A continuous time signal , where t is in seconds, is the input to a linear time invariant (LTI) filter with the impulse response Let y(t) be the output of this filter. The maximum value of |y(t)| is _

Two discrete-time signals x[n] and h[n] are both non-zero for n = 0, 1, 2 and are zero otherwise. It is given that x[0]=1, x[1]=2, x[2]=1, h[0]=1. Let y[n] be the linear convolution of x[n] and h[n].