Semiconductor Devices and Logic Gates

In the given circuit, if $A=0, B=1$ and $C=1$ are inputs, then the values of $y_1$ and $y_2$ are respectively

In a transistor, if the collector current is $98 \%$ of emitter current, then the ratio of the base and collector currents is

The logic gate equivalent to the combination of logic gates shown in the figure is

At absolute zero temperature, an intrinsic semiconductor behaves as

\(\text { In the given options, the diode that is forward biased is }\)

In a common emitter transistor amplifier the resistance of collector is $3 \mathrm{k} \Omega$. If the current amplification factor is 100 and the base resistance is $2 \mathrm{k} \Omega$, then the power gain of the transistor is

The logic gate equivalent to the circuit given in the figure is

If $X, Y$ and $Z$ are the sizes of the emitter, base and collector of a transistor respectively, then

The logic gate equivalent to the circuit shown in the figure is

The voltage gain and the current amplification factor of a transistor in common emitter configuration are 300 and 60 respectively. If the collector resistance is $5 \mathrm{k} \Omega$, then the base resistance is

If three logic gates are connected as shown in the figure, then the correct truth table of the circuit is

In common emitter amplifier of a transistor, if the ratio of the voltage gain and current amplification factor is 4 , then the ratio of the collector and base resistances is

A transistor has 3 impurity regions of different doping levels. In the order of increasing doping level, the regions are

When three NAND logic gates are connected as shown in the figure, then the logic gate equivalent to the circuit is

The device used for voltage regulation is

If five logic gates are connected as shown in the figure, then the values of $y_1, y_2$ and $y_3$, are respectively

A transistor works as an amplifier when

A Zener diode of breakdown voltage 20 V is connected as shown in the given circuit. The current through Zener diode is

The voltage gains of two amplifiers connected in series are 8 and 12.5 . If the voltage of the input signal is $200 \mu \mathrm{~V}$, then the voltage of the output signal is

\(\text { The following configuration of gates is equivalent to }\)

In the diodes show in the diagrams, which one is reverse biased?

Four logic gates are connected as shown in the figure. If the inputs are $A=0, B=1$ and $C=1$, then the values of $Y_1$ and $Y_2$ respectively, are

The current gain of a transistor in common emitter configuration is 80 . The resistances in collector andbase sides of the circuit are $5 \mathrm{k} \Omega$ and $1 \mathrm{k} \Omega$ respectively. If the input voltage is 2 mV , the output v...

\(\text { Truth table for the given circuit is }\)

If $R_C$ and $R_B$ are respectively the resistances of in collector and base sides of the circuit and $\beta$ is the current amplification factor, then the voltage gain of a transistor amplifier in common emitter configuration is

The semiconductor used for fabrication of visible LEDS must at least have a band gap of

In a common emitter amplifier, AC current gains 40 and input resistance is $2 \mathrm{k} \Omega$. The load resistance is given as $10 \mathrm{k} \Omega$. Then, the voltage gain is

Pure silicon at 300 K has equal electron and hole concentration of $1.5 \times 10^{16} \mathrm{~m}^{-3}$. If the hole concentration increases to $3 \times 10^{22} \mathrm{~m}^{-3}$, then electron concentration in the silicon is

In $n-p-n$ transistor circuit, the collector current is 10 mA . If $95 \%$ of the electrons emitted reach the collector, then the base current is nearly

A p-n junction diode is used as

The voltage gain and current gain of a transistor amplifier in common emitter configuration are respectively 150 and 50 . If the resistance in the base circuit is $850 \Omega$, then the resistance in collector circuit is

If the energy gap of a substance is 5.4 eV , then the substance is

When a signal is applied to the input of a transistor, it was found that output signal is phase-shifted by $180^{\circ}$. The transistor configuration is

In the given digital circuit, if the inputs are $A=1 B_x$ and $C=1$, then the value of $Y_1$ and $Y_2$ are respectino

If $n_r$ and $n_h$ are concentrations of electron and holes in a semiconductor, then the intrinsic carrier concentration $n_j$ in thermal equilibrium is

\(\text { In a } p-n-p \text { transistor }\)

A $p-n$ junction diode is reverse biased with a voltage of 8 V . If the resistance of the diode is $4 \times 10^7 \Omega$, then the reverse saturation current is

In a transistor, when the emitter current changes by 9.85 mA , the collector current changes to 9.5 mA . Then, the base current is

The material used in the fabrication of infrared LED's is

Output of following logic circuit is

Consider the statements
In a semiconductor
(A) There are no free electrons at 0 K.
(B) There are no free electrons at any temperature.
(C) The number of free electrons increases with temperature.
(D) The number of free electrons is less tha...

The truth table given below corresponds to logic gate.

A change of \(0.04 \mathrm{~V}\) takes place between the base and the emitter when an input signal is connected to the common emitter transistor amplifier. As a result, \(20 ~\mu \mathrm{A}\) change takes place in the base current and a cha...

The output current versus time curve of a
rectifier is shown in the figure. The average
value of output current in this case is ........... .

A transistor is connected in common emitter configuration. The collector supply is \(8 \mathrm{~V}\) and the voltage drop across a resistor of \(800 \Omega\) in the collector circuit is \(0.5 \mathrm{~V}\). If the current gain factor $$\alp...