### GATE 1994 ECE Analog Circuits (Analog Electronics) - Video Solutions

1. A Ramp voltage v(t) = 100t volts is applied to a RC differentiating circuit with R = 5 kΩ and C = 4 µF. The maximum output voltage is ______
a. 0.2 volts
b. 2.0 volts
c. 10.0 volts
d. 50.0 volts

2. A class-A transformer coupled transistor power amplifier is required to deliver a power output of 10 watts. The maximum power rating of the transistor should not be less than ______
a. 5 watts
b. 10 watts
c. 20 watts
d. 40 watts

3. In order to reduce the harmonic distortion in an amplifier, its dynamic range has to be _________

4. A common emitter transistor amplifier has a collector current of 1.0 mA when its base current is 25 µA at room temperature. Its input resistance is approximately equal to _______

5. A pulse having a rise time of 40 nsec is displayed on a CRO of 12 MHz bandwidth. The rise time of the pulse as observed on the CRO would be approximately equal to ____________

6. For the 2N338 transistor, the manufacturer specifies Pmax = 100 mW at 25oC, free air temperature and the maximum junction temperature Tjmax = 125oC. Its thermal resistance is ________

7. The frequency compensation is used in operational amplifiers is to increase its ___________

8. Match the following:
a) Hartley 1) Low frequency oscillator
b) Wein-bridge 2) High frequency oscillator
c) Crystal 3) stable frequency oscillator
4) Relaxation frequency oscillator
5) Negative resistance oscillator

9. Assuming that the amplifier shown in the figure below is a voltage controlled voltage source.
Show that the voltage transfer function of the network is given by

10. Calculate the frequency at which zero transmission is obtained from the Wien-bridge shown below.

11. Find the output voltage of the following circuit shown below, assuming ideal operational amplifier behavior.

12. In the MOSFET amplifier shown in the figure below, the transistor has µ = 50, rd = 10 kΩ, Cgs = 5 pF, Cgd = 1 pF and Cds = 2 pF.

Draw a small signal equivalent circuit for the amplifier for mid band calculate its mid band voltage gain.