Semiconductor Devices and Logic Gates

On increasing the reverse bias to a large value in a P-N junction diode, current

If two inputs of a NAND gate are shorted, the resulting gate is

The following graph represents

Doping of a semiconductor (with small impurity atoms) generally changes the resistivity as follows.

If the maximum efficiency of a full wave rectifier is \(x \%\) and that of half-wave rectifier is \(y \%\), then the relation between \(x\) and \(y\) is

The Boolean expression for the following combination is

When forward bias is applied to a p-n junction, then what happens to the potential barrier \(\left(V_B\right)\) and the width \((\mathrm{X})\) of the depletion region?

The logic gate combination circuit shown in the figure performs the logic function of

The following logic gate combination is equivalent to

In which figure, the junction diode is forward biased?

Which one of the following statements is WRONG regarding LED?

In the following digital logic circuit, the output Y will be '1' for inputs

In the case of NAND gate, if A and B are the inputs and \(\mathrm{Y}\) is the output then

In energy band diagram of insulators, a band gap and the conduction band is respectively

Identify the correct circuit diagrams for the normal operation from the following.

In the digital circuit the inputs are as shown in figure. The Boolean expression for output \(\mathrm{Y}\) is

If \(p\)-\(n\) junction diode is in forward bias then

In the study of transistor as an amplifier if \(\alpha=\frac{I_C}{I_E}=0.98\) and \(\beta=\frac{I_C}{I_B}=49\), where \(I_C, I_B\) and \(\mathrm{I}_{\mathrm{E}}\) are collector, base and emitter current respectively then $$\left(\frac{1}{\a...

Identify the mismatch out of the following.

In insulators

To obtain the truth-table shown, from the following logic circuit, the gate G should be

For the diagram shown, the resistances between points A and B when ideal diode D is forward biased is '\(R_1\)' and that when reverse biased is '\(R_2\)'. The ratio \(R_1: R_2\) is

Which one of the operations of \(\mathrm{n}-\mathrm{p}-\mathrm{n}\) transistor differs from that of \(p-n-p\) transistor?

The output of an 'OR' gate is connected to both the inputs of a 'NAND' gate. The combination will serve as

A pure \(\mathrm{Si}\) crystal has \(4 \times 10^{28}\) atoms per \(\mathrm{m}^3\). It is doped by 1 ppm concentration of antimony. The number of free electrons available will be

The given circuit has two ideal diodes \(D_1\) and \(D_2\) connected as shown in the figure. The current flowing through the resistance \(R_1\) will be

For a NAND gate, the inputs and outputs are given below.

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Two identical ideal diodes are connected to an ammeter and a d.c source (1 volt) as shown. In which one of the following circuits, ammeter will not show any deflection?

For the output of the following logic circuit to be 'I', the values of inputs A and B should be respectively

A p-n junction photodiode is fabricated from a semiconductor with a band gap of \(2.5 \mathrm{~eV}\). It can detect a signal of wavelength
[Planck's constant $$=6.6 \times 10^{-34} \mathrm{Js}, \mathrm{c}=3 \times 10^8 \mathrm{~m} / \mathrm...

For a transistor, the current ratio \(\alpha_{\mathrm{dc}}=\frac{69}{70}\), the current gain \(\beta_{\mathrm{dc}}\) is

Choose the correct statement. In conductors

The input a.c. voltage of frequency \(60 \mathrm{~Hz}\) is applied to half-wave rectifier and also to full-wave rectifier. The output frequency in case of half-wave rectifier and that in case of full wave rectifier is respectively.

The resultant gate and its Boolean expression in the given circuit is

What are the values of the currents flowing in each of the following diode circuits \(\mathrm{X}\) and \(\mathrm{Y}\) respectively? (Assume that the diodes are ideal)

In common emitter amplifier, a change of 0.2 mA in the base current causes a change of 5 mA in the collector current. If input resistance is 2 k\(\Omega\) and voltage gain is 75, the load resistance used in the circuit is

When the temperature of a semiconductor is increased, its resistance and electric conductivity respectively.

For a two input AND gate, the four entries are shown in the truth table. Identify the correct ones out of these \((\mathrm{A}, \mathrm{B}=\) input, \(\mathrm{Y}=\) output)

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In a CE transistor, a change of \(8.0 \mathrm{~mA}\) in the emitter current produces a change of \(7.8 \mathrm{~mA}\) in the collector current. What change in the base current is necessary to produce the same change in the collector current...

In an n-p-n transistor 200 electrons enter the emitter in 10\(^{-8}\) second. If 1% electrons are lost in the base, then the current that enters the emitter and the current amplification factor are respectively [e = 1.6 \(\times\) 10$$^{-19...

Choose the FALSE statement from the following.

A logic gate which gives output 'HIGH' only when its two input terminals are at different logic levels with respect to each other is

Which of the following gates will give an output '1' for the given inputs?

Choose the correct statement. In semiconductors valance band and conduction band

For a common-emitter amplifier, the voltage gain is 40. Its input and output impedances are \(100 \Omega\) and \(400 \Omega\), respectively. The power gain of the CE amplifier will be

The current in the following circuit is

For a transitor, \(\frac{1}{\alpha_{\mathrm{DC}}}-\frac{1}{\beta_{\mathrm{DC}}}\) is equal to [ \(\alpha_{\mathrm{DC}}\) and \(\beta_{\mathrm{DC}}\) are current amplification factors]

In a pure silicon, number of electrons and holes per unit volume are \(1.6 \times 10^{16} \mathrm{~m}^{-3}\). If silicon is doped with Boron in a way that on doping hole density increases to \(4 \times 10^{22} \mathrm{~m}^{-3}\). Then elect...

LED is manufactured using zinc selenide then it emits.

In an ideal junction diode, the current flowing through PQ is