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  Choose the correct answer for the following (10 x 2)   1. An op-amp has a voltage gain of 1,00,000 operates with a supply voltage of ± 15 V. If a difference voltage of 1 V is applied at its input, then the output voltage should be (a) 0 (b) 1,00,000 V (c) Cannot be more than ± 15 V (d) 1 V   2. A DC power supply has open circuit voltage of 100 V. When the full load current is drawn, the output drops to 80 V. The percentage voltage regulation is (a) 84% (b) 25% (c) 20% (d) 40 % 3. The minimum number of comparators required to build an 8-bit flash ADC is (a) 8 (b) 63 (c) 255 (d) 256 4. An AM transmitter has carrier power output of 50 W. Total Power produced with 80 % modulation is (a) 66 W (b) 60 W (d) 40W (d) 36 W 5. If the differential voltage gain and common mode voltage gain of a differential amplifier arc 48 dB and 2 dB respectively; then its common mode rejection ratio is (a) 23 dB (b) 25 dB (c) 46 dB (d) 50dB 6. A 741 type op-amp has a gain-bandwidth product of 1 M...

Choose the correct answer for the following (10 x 2)   1. When a differential amplifier is operated single ended, (a) The output is grounded (b) One input is grounded, and a signal is applied to the other (c) Both inputs are connected together (d) The output is not inverted   2. I f A DM = 3500; A CM = 0.35, the CMRR is_______ (a) 1225 (b) 10,000 (c) 80 dB (d) Answers (b) and (c)   3. Negative feedback _____ (a) Increases the input and output impedances (b) Increases the input impedance and bandwidth (c) Decreases the output impedance and bandwidth (d) Does not affect impedance or bandwidth.   4. The cut-off frequency of a first-order low-pass filter for RI = 2.5 kW and CI = 0.05 µF is (a) 1.273 kHz (b) 12.73 kHz (c) 127.3 kHz (d) 127.3 Hz   5. Which among the following does not belong to the category of LC oscillators? (a) Hartley oscillator (b) Colpitt’s oscillator (c) Clapp oscillator (d) Wein bridge oscillator   6. Which among the following is not an ...

  Choose the correct answer for the following (10 x 2)   1. Compared to NMOS OP-AMP, most CMOS OP-AMPs have (a) higher CMRR (b) lower CMRR (c) lower slew rate (d) higher power dissipation   2. The operational transconductance amplifier is a single chip amplifier in which the transconductance is controlled by an externally connected (a) resistance (b) capacitor (c) choke (d) voltage 3. In a full-wave rectifier, independently of the filter used, the peak inverse voltage across each diode divided by the maximum transformer voltage measured from midpoint to either end equals to (a) 0.25 (b) 0.50 (c) 10 (d) 2.0 4. For Butterworth & Chebyshev filters, the correct statement is: (a) Butterworth response has a sharp cut-off (b) Chebyshev response has a flat response in the pass band (c) Butterworth response has ripples in the pass band (d) Chebyshev response has ripples in the pass band 5. A zero crossing detector converts a sinusoid into a (a) saw tooth wave (b) triangular wa...

  Choose the correct answer for the following (10 x 2)   1. In the common mode, (a) Both inputs are grounded (b) The outputs are connected together (c) An identical signal appears on both the inputs (d) The output signal are in-phase   2. The differential gain is ____ (a) Very high (b) Very low (c) Dependent on input voltage (d) About 100   3. The input impedance of a differential amplifier equals r’e times _____ (a) β (b) RE (c) RC (d) 2β   4. An astable multivibrator also known as (a) One shot multivibrator (b) Free-running multivibrator (c) Biastable multivibrator (d) Monostablc multivibrator   5. Which among the following are regarded as three-pin voltage regulator ICs ? (a) Fixed voltage regulators (b) Adjustable voltage regulators (c) Both (a) and (b) (d) None of the above   6. The standard value for Intermediate Frequency (IF) in double conversion FM receivers is (a) 455 KHz (b) 580 KHz (c) 10.7 MHz (d) 50 MHz   7. Operations of computer ar...

Choose the correct answer for the following (10 x 2) 1. An example of a military-grade op-amp with a higher slew rate is (a) 741 (b) 741 C (c) 741 A (d) 741 S 2. A non-inverting amplifier with a gain of 100 is nulled at 25°C. Determine the output voltage if the temperature rises to 40°C for an offset voltage drift of 0.15 MV/°C. (a) 600 MV (b) 450 MV (c) 225 MV (d) 60 MV 3. An example of a negative regulator is (a) LM117 (b) LM137 (c) LM217 (d) LM317 4. The operational transconductance amplifier outputs a current proportional to its (a) Input voltage (b) Input resistance (c) Input capacitance (d) Input conductance 5. A second-order low-pass filter has a roll-off rate of (a) - 40 dB/octave (b) - 40 dB/decade (c) - 20 dB/octave (d) - 20 dB/decade 6. A quadrature oscillator generates both  (a) Cosine wave and rectangular wave  (b) Cosine wave and triangular wave  (c) Cosine wave and sawtooth wave  (d) Cosine wave and sine wave 7. A pulse position modulator can be built ...

Multiple Choice Questions: (10 x 2) 1. Assume the OP-Amp to be ideal, the voltage gain of the amplifier as shown is: (a) -R 2 /R 1 (b) -R 3 /R 1 (c) -R 2 ∥R 3 /R 1 (d) -(R 2 +R 3 )/R 1 2. In the rectifier signal level diode 1N4007 can be connected with (a) With the 220 V AC power supply (b) With the 220 V DC power supply (c) With the 12 V AC power supply (d) With the 12 V DC power supply 3. Su ppose that the modulating signal is m(t)=2cos(2πf m t) and the carrier signal is x c (t) = A c cos(2πf c t), which one of the following is a conventional AM signal without over-modulation? (a)  (b)  (c)  (d)  4. The ideal Op Amp has the following characteristics ( a) R i  = ∞; A v  = ∞; R 0  = 0 (b) R i  = 0; A v  = ∞; R 0  = 0 (c) R i  = 0; A v  = 0; R 0  = 0 (d) R i  = ∞; A v  = ∞; R 0  = ∞ 5. In quartz watches which oscillator is preferred (a) RC phase shift os...