List of top Analog Electronics Questions asked in GATE IN

The RLC filter shown below acts as a ________.
In the circuit shown below, \(R\) is \(1\ \text{k}\Omega\) and \(R_f\) is \(10\ \text{k}\Omega\). If \(V_{in}\) is \(100\) mV and the op-amps have supply voltages of \(\pm15\) V, then \(V_{out}\) is ______ V.
In the circuit below the maximum value of \(v_{out}\) is ________ V. (rounded off to the nearest integer)
The maximum signal to quantization noise ratio (SQNR) for a \(16\)-bit analog-to-digital converter is approximately _________ dB.
In the phase-locked-loop (PLL) circuit shown below, the output of the VCO (voltage-controlled oscillator) is a digital square wave.

If the input is a square wave at \(10\) kHz, the steady state frequency of the output is kHz (rounded off to the nearest integer).
In the circuit shown, the BJT has a \(\beta\) of \(100\). The base-emitter junction voltage is \(0.65\) V. The quiescent collector current, \(I_C\), is _______ mA.
In the following active filter circuit with ideal op-amps, \(R\) is \(1\ \text{k}\Omega\), \(C\) is \(1\ \mu\text{F}\), and \(V_{in}\) has an amplitude of \(1\) V at \(1000\) rad/s.

The amplitude of \(V_{out}\) is __________ V.
A common gate amplifier represents a _____________.
An amplitude modulated voltage signal \(x(t)\) drives a load of \(1\,\Omega\).
\[ x(t) = K\cos(300\pi t) + L\cos(240\pi t) + L\cos(360\pi t) \]
If the efficiency is \(60\%\) and the carrier power is \(50\) W, the value of \(L\) is ______ V.
The minimum number of comparators required in a \(6\)-bit flash analog-to-digital converter is ________. (answer in integer)
In the circuit shown, the capacitance \( C_0 = 10 \, \mu\text{F} \) and inductance \( L_0 = 1 \, \text{mH} \) and the diode is ideal. The capacitor is initially charged to 10 V and the current in the inductor is initially zero. If the switch is closed at \( t = 0 \, \text{s} \), the voltage \( V_C(t) \) (in volts) across the capacitor at \( t = 0.5 \, \text{s} \) is _________ (round off to one decimal place)
A 1 kHz sine-wave generator having an internal resistance of 50Ω generates an open-circuit voltage of 10 Vp-p. When a capacitor is connected across the output terminals, the voltage drops to 8 Vp-p. The capacitance of the capacitor (in microfarads) is _________.
In the circuit shown, \(R_1 = 100 \, \text{k}\Omega\) and \(R_2 = 1 \, \text{k}\Omega\). If the base-to-emitter voltage of the npn BJT is 0.7 V and the collector-to-emitter voltage is 5.2 V, the \(\beta\) (current gain) of the BJT is _________ (round off to two decimal places).
The circuit shown is driven by a sinusoidal input voltage, \( V_{\text{in}} \), resulting in the output voltage, \( V_{\text{out}} \). The frequency (in kilohertz) at which the voltage gain is 0 dB is _________ (round off to two decimal places)
In the small signal circuit shown, the enhancement mode n-channel MOSFET is biased in saturation with transconductance \( g_m \). If channel length modulation is ignored, the small signal impedance looking into the node P is given by _________
In the small signal circuit shown, the enhancement mode n-channel MOSFET is biased in saturation with a transconductance \( g_m \). A small signal low-frequency voltage \( v_d \) injected at the supply terminal results in a small signal voltage fluctuation \( v_o \) at the output. If the channel length modulation of the MOSFET is ignored, the small signal gain \( \frac{v_o}{v_d} \) is given by _________
A resistor ladder digital-to-analog converter (DAC) receives a digital input that results in the circuit having the state as shown in the figure. For this digital input, the Thevenin voltage, \( V_{th} \), and Thevenin resistance, \( R_{th} \), as seen at the output node are _________
A Zener diode is used as a 4 V voltage regulator in the circuit shown. Given that the diode requires a minimum current of 4 mA for voltage regulation, the maximum current (in milliamperes) permitted to flow through the load \( R_L \) is _________ (round off to one decimal place)
A signal \( V_{\text{in}}(t) \) shown is applied from \( t = 0 \) ms to \( t = 6 \) ms to the circuit shown. Given the initial voltage across the capacitor is 0.3 V, and that the diode is ideal, the open circuit voltage \( V_{\text{out}}(t) \) at \( t = 5 \) ms is _________
An OPAMP has a gain of \( 10^4 \), an input impedance of 10 MΩ and an output impedance of 100Ω. The OPAMP is used in unity-gain feedback configuration in a voltage buffer circuit. The closed-loop output impedance of the OPAMP (in milliohms) in the circuit is _________.
In the bandpass filter circuit shown, \( R_0 = 50 \, \Omega \), \( L_0 = 1 \, \text{mH} \), \( C_0 = 10 \, \text{nF} \). The Q factor of the filter is _________ (round off to two decimal places).
An analog-to-digital converter with resolution 0.01 V converts analog signals between 0 V to +10 V to an unsigned binary output. The minimum number of bits (in integer) in the output is _________

The diode used in the circuit has a fixed voltage drop of 0.6 V when forward biased. A signal \( v_s \) is given to the ideal OpAmp as shown. When \( v_s \) is at its positive peak, the output \( (v_{OA}) \) of the OpAmp in volts is \(\underline{\hspace{2cm}}\). 

The transistor Q1 has a current gain \( \beta_1 = 99 \) and the transistor Q2 has a current gain \( \beta_2 = 49 \). The current \( I_{B2} \) in microampere is \(\underline{\hspace{2cm}}\). 

The output \( V_o \) of the ideal OpAmp used in the circuit shown below is 5 V. Then the value of resistor \( R_L \)in kilo ohm (kΩ) is: