Semiconductor Electronics

A zener of breakdown voltage $V_Z=8$ V and maximum zener current, $I_{ZM}=10$ mA is subjected to an input voltage $V_i=10$ V with series resistance $R=100\ \Omega$. In the given circuit $R_L$ represents the variable load resistance. The ratio of maximum and minimum value of $R_L$ is ______.

A potential barrier of 0.4 V exists across a p-n junction. An electron enters the junction from the n-side with a speed of $6.0\times10^5$ ms$^{-1}$. The speed with which electron enters the p side will be $\dfrac x3\times10^5$ ms$^{-1}$ the value of $x$ is ______.

(Given mass of electron $=9\times10^{-31}$ kg, charge on electron $=1.6\times10^{-19}$ C.)

The circuit diagram used to study the characteristic curve of a zener diode is connected to variable power supply (0 - 15 V) as shown in figure. A zener diode with maximum potential $V_z=10$ V and maximum power dissipation of 0.4 W is connected across a potential divider arrangement. The value of resistance $R_P$ connected in series with the zener diode to protect it from the damage is ______ $\Omega$.

In the circuit, the logical value of A = 1 or B = 1 when potential at A or B is 5 V and the logical value of A = 0 or B = 0 when potential at A or B is 0 V.

The truth table of the given circuit will be :

The energy band gap of semiconducting material to produce violet (wavelength = 4000 Å) LED is ______ eV. (Round off to the nearest integer).

Two ideal diodes are connected in the network as shown is figure. The equivalent resistance between A and B is ______ $\Omega$.

In the circuit shown below, maximum zener diode current will be ______ mA.

A logic gate circuit has two inputs A and B and output Y. The voltage waveforms of A, B and Y are shown below.

The logic gate circuit is:

Identify the solar cell characteristics from the following options :

If the potential barrier across a p-n junction is 0.6 V. Then the electric field intensity, in the depletion region having the width of $6\times10^{-6}$ m, will be _______ $\times10^5$ N/C.

A 8 V Zener diode along with a series resistance R is connected across a 20 V supply (as shown in the figure). If the maximum Zener current is 25 mA, then the minimum value of R will be _______ Ω.

The I-V characteristics given in above figure is related to:

In connection with the circuit drawn below, the value of current flowing through 2 kΩ resistor is _______ $\times10^{-4}$ A.

What is the conductivity of a semiconductor sample having electron concentration of $5\times10^{18}$ m$^{-3}$, hole concentration of $5\times10^{19}$ m$^{-3}$, electron mobility of 2.0 m$^2$V$^{-1}$s$^{-1}$ and hole mobility of 0.01 m$^2$V$^{-1}$s$^{-1}$ ?

(Take charge of electron as $1.6\times10^{-19}$ C)

The V-I characteristic of a diode is shown in the figure. The ratio of forward to reverse bias resistance is :

The temperature dependence of resistances of Cu and undoped Si in the temperature range 300-400 K, is best described by :

If a, b, c, d are inputs to a gate and $x$ is its output, then, as per the following time graph, the gate is :

Identify the semiconductor devices whose characteristics are given below, in the order (a), (b), (c), (d) :

The truth table given in fig. represents :

A	B	Y
0	0	0
0	1	1
1	0	1
1	1	1

An experiment is performed to determine the I - V characteristics of a Zener diode, which has a protective resistance of R = 100 Ω, and a maximum power of dissipation rating of 1 W. The minimum voltage range of the DC source in the circuit is :