GATE Electronics & Communication

Which of the following statements is/are TRUE with respect to an ideal opamp?

Which of the following statements is/are TRUE with respect to ideal MOSFET-based DCcoupled single-stage amplifiers having finite load resistors?

Which of the following statements is/are true for a BJT with respect to its DC current gain $\beta$?

An NMOS transistor operating in the linear region has $I_{D}$ of 5 $\mu$A at $V_{DS}$ of 0.1 V. Keeping $V_{GS}$ constant, the $V_{DS}$ is increased to 1.5 V. Given that $\mu_{n}C_...

A cascade of common-source amplifiers in a unity gain feedback configuration oscillates when

A sample and hold circuit is implemented using a resistive switch and a capacitor with a time constant of 1 $$\mu$$s. The time for the sampling switch to stay closed to charge a ca...

Consider an ideal long channel nMOSFET (enhancement-mode) with gate length 10 $$\mu$$m and width 100 $$\mu$$m. The product of electron mobility ($$\mu$$ n ) and oxide capacitance p...

For an $n$-channel silicon MOSFET with 10 nm gate oxide thickness, the substrate sensitivity ( $\partial V_T / \partial\left|V_{B S}\right|$ ) is found to be $50 \mathrm{mV} / \mat...

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

Which one of the following statements is correct about an ac-coupled common- emitter amplifier operating in the mid-band region?

For a given sample-and-hold circuit, if the value of the hold capacitor is increased, then

A BJT in common-base configuration is used to amplify a signal received by a $$50\,\Omega $$ antena. Assume kT/q = 25 mV. The value of the collector bias current ( in mA ) required...

The desirable characteristics of a transconductance amplifier are

A BJT is baised in forward active mode Assume V BE = 0.7 V, kT/q = 25 mV and reverse saturation current I s = 10 -13 A. The transconductance of the BJT (in mA/V) is

If the emitter resistance in a common-emitter voltage amplifier is not bypassed, it will

A good current buffer has

For a BJT, the common-base current gain $$\alpha = \,\,0.98$$ and the colector base junction reverse bias saturation current I co = 0.6 $$\mu {\rm A}$$. This BJT is connected in th...

In a transconductance amplifier , it is desirable to have

The input impedance (Z i ) and the output impedance (Z o ) of an ideal transconductance (voltage controlled current source) amplifier are

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 o =$$\infty $$ Which of the following Q-poin...

The cascode amplifier is a multistage configuration of

The effect of current shunt feedback in an amplifier is to

An ideal Op-Amp is an ideal

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

A bipolar transistor is operating in the active region with a collector current of 1mA. Assuming that the 'β' of the transistor is 100 and the transconductance (g m ) and the input...

If the differential voltage gain and the common mode voltage gain of a differential Amplifier are 48 dB and 2 dB respectively, then it's common mode Rejection Ratio is

Three identical amplifiers with each one having a voltage gain of 50, input Resistance of 1 KΩ and output resistance of 250Ω, are cascaded. The open circuit voltage gain of the com...

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

Generally, the gain of a transistor Amplifier falls at high frequency due to the

An amplifier without feedback has a voltage gain of 50, input Resistance of 1 k$$\Omega $$ and output Resistance of 2.5 k$$\Omega $$ . The input Resistance of the current-shunt neg...

The circuit in the figure employs positive Feedback and is intended to generate sinusoidal oscillation. If at a frequency f$$_0$$, B(f)= $${{\Delta {V_f}(f)} \over {{V_0}(f)}} = {1...

In a negative feedback amplifier using voltage - Series (i.e., voltage - sampling, series mixing) feedback

Consider the following two statements. Statement 1: Astable Multivibrator can be used for generating Square Wave. Statement 2: Bistable Multivibrator can be used for storing binary...

The current gain of a BJT is

An npn BJT has g m = 38 mA/V, $${C_\mu }\, = {10^{ - 14}}$$ F, $${C_\pi }\, = 4\, \times {10^{ - 13}}\,F$$ and DC current gain $$\beta \, = \,90$$. For this transistor f T and $${f...

An Amplifier using an Op-Amp with a Slew-Rate SR = V/$$\mu $$sec, has a gain of 40 dB. If this amplifier has to faith fully amplify sinsoidal signals from dc to 20 KHz. Without int...

The ideal Op-Amp has the following characteristics.

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

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

The most commonly used Amplifier in sample and hold circuit is

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

Crossover distortion behavior is characteristic of

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

An amplifier has an open loop gain of 100, an input impedance of 1 k$$_\Omega $$, and an output impedance of 100 $$_\Omega $$ . A feedback network with a feedback factor of 0.99 is...

An amplifier is assumed to have a single pole high frequency transfer function. The rise time of its output response to a step function input is 35 nsec. The upper 3 dB frequency (...

An NPN transistor (with $${C_\pi }\,\, = \,\,0.3\,\,$$ pf) has a unity gain cutoff frequency $${f_T}$$ of 400 MHz at a DC-bias current I c = 1mA. The value of its $${C_\mu }$$ (in...

Negative feedback in an amplifier

For full wave rectification, a four diode bridge rectifier is claimed to have the following advantages over a two diode circuit: (1) less expensive transformer (2) smaller size tra...

From a 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:

The emitter coupled pair of BJT’s gives a linear transfer relation between the differential output voltage and the differential input voltage V id only. When the magnitude of V id...

In a series regulated power supply circuit, the voltage gain A v of the ‘pass’ transistor satisfies the condition:

In a differential Amplifier, CMRR can be improved by using an increased

The $${f_T}$$ of a BJT is related to its $${g_{m,}}\,\,{C_\pi }$$ and $${C_\mu }$$ as follows

One input terminal of high gain comparator circuit is connected to ground and a sinusoidal voltage is applied to the other input. The output of comparator will be

In a shunt-shunt negative feedback Amplifier, as compared to the basic Amplifier,

Negative feedback in 1. Voltage series configuration 2.Current shunt configuration (a) increases input impedance (b) decreases input impedance (c) increases closed loop gain (d) le...

An npn transistor has a beta cut-off frequency $${f_\beta }$$ of 1MHz and Common Emitter short circuit low frequency current gain $${\beta _o}$$ of 200. The unity gain frequency $$...

Match the following. Group - I (a)Cascode amplifier (b)Differential Amplifier (c)Darlington pair common-collector Amplifier Group - II (1)does not provide current gain (2)is a wide...

A BJT is said to be operating in the saturation region if

A power Amplifier delivers 50 W output at 50% efficiency. The ambient temperature is 25$$^\circ $$ C. if the maximum allowable junction temperature is 150 $$^\circ $$ C, then the m...

An n-channel JFET has I DSS = 1 mA and V p = -5 V. Its maximum transconductance is ______

A change in the value of the Emitter resistance (R e in a difference Amplifier.

An RC-Coupled Amplifier is assumed to have a single-pole low frequency transfer function. The maximum lower-cutoff frequency allowed for the Amplifier to pass 50 Hz square wave wit...

An op-Amp is used as a zero-crossing detector. If maximum output available from the Op-Amp is $$ \pm 12\,\,{V_{p - p}}$$ and the slew rate of the Op-Amp is 12 $$V/\mu $$ sec then t...

To obtain very high input and output impedances in a feedback Amplifier, the mostly used is

An Amplifier has an open-loop gain of 100 and its lower and upper-cut-off frequency of 100 Hz and 100 kHz respectively, a feedback network with a feedback factor of 0.99 is connect...

In order to reduce the harmonic distortion in an amplifier, its dynamic range has to be _________

A common emitter transistor amplifier has a collector current of 1.0 mA when its base current is 25 $$\mu$$A at the room temperature. It's input resistance is approximately equal t...

A class-A transformer coupled, transistor power Amplifier is required to deliver a power rating of the transistor should not be less than.

The frequency compensation is used in OP-Amps to increase its___________

Match the following. GROUP-1 (A) Hartley (B) Wein-bridge (C) Crystal GROUP-2 (1) Low frequency oscillator (2) High frequency oscillator (3) Stable frequency oscillator (4) Relaxati...

The transit time of a current carriers through the channel of an FET decides its ____________characteristics.

The bandwidth of an n-stage tuned amplifier, with each stage having a band width of B, is given by

Negative feedback in Amplifiers.

In a multi-stage RC-Coupled Amplifier the coupling capacitor.

In a transistor push-pull Amplifier

An n-channel JFET has a pinch-off voltage of V p = -5V. V DS (max) = 20V and g m = 2mA/V. The minimum 'ON' resistance is achieved in the JFET for

Two non-inverting amplifiers, one having a unity gain and other having a gain of twenty, are made using identical operational gain amplifier, the amplifier with gain twenty has

Which of the following statements are correct for basic transistor Amplifier configurations?

Of the four biasing circuits shown in Fig. For a BJT, indicate the one which can have maximum bias stability: