GATE EC Electronic Devices questions

In the circuit shown below, the knee current of the ideal Zener diode is $10\: mA.$ To maintain $5\: V$ across $R_{L},$ the minimum value of $R_{L}$ in $\Omega$ and the minimum power rating of the Zener diode in $mW,$ respectively, are

The following arrangement consists of an ideal transformer and an attenuator which attenuates by a factor of $0.8.$ An ac voltage $V_{WX1} = 100V$ is applied across $WX$ to get an open circuit voltage $V_{YZ1}$ across $YZ.$ Next, an ac voltage $V_{YZ2}= 100V$ is applied across $YZ$ to get an open circuit voltage $V_{WX2}$ across $WX.$ Then …

The small-signal resistance $(i.e., dV_{B}/dI_{D})$ in $k\Omega$ offered by the $n$-channel $MOSFET\: M$ shown in the figure below, at a bias point of $V_{B} = 2\: V$ is (device data for $M:$ device transconductance parameter $k_{N} = \mu_{n} C'_{ox} (W/L) = 40\: \mu A/V^{2},$threshold voltage $V_{TN} = 1\: V,$ and neglect body effect and …

The ac schematic of an $NMOS$ common-source stage is shown in the figure below, where part of the biasing circuits has been omitted for simplicity. For the $n$-channel $MOSFET\: M,$ the transconductance $g_{m} = 1\; mA/V,$ and body effect and channel length modulation effect are to be neglected. The lower cutoff frequency in $Hz$ of the circuit is …

Three capacitors $C_{1}, C_{2}$ and $C_{3}$ whose values are $10\mu F, 5\mu F,$ and $2\mu F$ respectively, have breakdown voltages of $10V, 5V,$ and $2V$ respectively. For the interconnection shown below, the maximum safe voltage in Volts that can be applied across the combination, and the corresponding total charge in $\mu C$ stored in the …

In the circuit shown below, the silicon $npn$ transistor $Q$ has a very high value of $\beta.$ The required value of $R_{2}$ in $k\Omega$ to produce $I_{C} = 1\: mA$ is

Consider the following figure The current $I_{S}$ in $\text{Amps}$ in the voltage source, and voltage $V_{S}$ in Volts across the current source respectively, are

Consider the following figure The current in the $1\Omega$ resistor in $\text{Amps}$ is

The current $i_b$ through the base of a silicon $npn$ transistor is $1+0.1\cos(10000\pi t)\:mA$. At $300\:K$, the $r_\pi$ in the small signal model of the transistor is

The $i-v$ characteristics of the diode in the circuit given below are $$i = \begin{cases} \frac{v-0.07}{500}\:A, & v\ge0.7\:V \\ \:\:\:\:\:\:\:\:0\:A, & v \lt 0.7\:V \end{cases}$$ The current in the circuit is

In the following figure, $C_1$ and $C_2$ are ideal capacitors. $C_1$ has been charged to $12\:V$ before the ideal switch $S$ is closed at $t=0$. The current $i(t)$ for all $t$ is

The source of a silicon ($n_i=10^{10}\:per\:cm^3$) n-channel MOS transistor has an area of $1\:sq\:\mu m$ and a depth of $1\:\mu m$. If the dopant density in the source is $10^{19}/cm^3$, the number of holes in the source region with the above volume is approximately

In the CMOS circuit shown, electron and hole mobilities are equal, and $M1$ and $M2$ are equally sized. The device $M1$ is in the linear region if

An infinitely long uniform solid wire of radius $a$ carries a uniform dc current of density $\overrightarrow{j}$. The magnetic field at a distance $r$ from the center of the wire is proportional to

An infinitely long uniform solid wire of radius $a$ carries a uniform dc current of density $\overrightarrow{j}$. A hole of radius $b$ (b < a) ia now drilled along the length of the wire at a distance $d$ from the center of the wire as shown below. The magnetic field inside the hole is

The values of voltage $\left(\mathrm{V}_{\mathrm{D}}\right)$ across a tunnel-diode corresponding to peak and valley currents are $\text{V}_{\text{P}}$ and $\text{V}_{\text{V}}$ respectively. The range of tunnel-diode voltage $\text{V}_{\text{D}}$ for which the slope of its $\text{I}-\text{V}_{\text{D}}$ characteristics is negative would be

The concentration of minority carriers in an extrinsic semiconductor under equilibrium is

Under low level injection assumption, the injected minority carrier current for an extrinsic semiconductor is essentially the

The majority carriers in an $n$-type semiconductor have an average drift velocity $\mathrm{V}$ in a direction perpendicular to a uniform magnetic field $\text{B}.$ The electric field $\mathrm{E}$ induced due to Hall effect acts in the direction

A heavily doped $n$-type semiconductor has the following data Hole-electron mobility ratio : $0.4$ Doping concentration : $4.2 \times 10^{8} \; \mathrm{atoms/m}^{3}$ Intrinsic concentration : $1.5 \times 10^{4} \; \mathrm{atoms/m}^{3}$ The ratio of conductance of the $n$-type semiconductor to that of the intrinsic semiconductor of same material and …