1
GATE EE 2001
Subjective
+5
-0
A simple active filter is shown in figure. Assume ideal op-amp. Derive the transfer function $${v_0}/{v_i}$$ of the circuit, and state the type of the filter (i.e., high-pass, low-pass, band-pass, or band-reject). Determine the required values of $${R_1},{R_2}$$ and $$C$$ in order for the filter to have a $$3$$-$$dB$$ frequency of $$1$$ $$kHz,$$ a high frequency input resistance of $$100\,\,k\Omega $$ and a high frequency gain magnitude of $$10.$$
2
GATE EE 1999
Subjective
+5
-0
The input voltage $${V_i}$$ in the circuit is a $$1$$ $$kHz$$ sine wave of $$1$$ $$V$$ amplitude. Assume ideal operational amplifiers with $$ \pm 15V\,\,DC$$ supply. Sketch on a single diagram the wave-forms of $${V_i},$$ $${V_1}$$ and $${V_0}$$ show, indicating the peak value of$${V_1}$$ and the average value $${V_0}$$.
3
GATE EE 1998
Subjective
+5
-0
In the circuit of figure $${R_s} = 2\,k\Omega ,$$ $${R_L} = 5\,k\Omega $$ For the op-amp $$A = {10^5},$$
$${R_i} = 100\,k\Omega ,\,\,{R_0} = 50\,k\Omega .$$ For $${V_0} = 10V.$$
Calculate $${V_S}$$ and $${{{V_0}} \over {{V_S}}}$$ and estimate the input resistance of the circuit,
$${R_i} = 100\,k\Omega ,\,\,{R_0} = 50\,k\Omega .$$ For $${V_0} = 10V.$$
Calculate $${V_S}$$ and $${{{V_0}} \over {{V_S}}}$$ and estimate the input resistance of the circuit,
4
GATE EE 1994
Subjective
+5
-0
Figure below shows an op-amp amplifier. Find the output voltage in steady state condition where $$(i)$$ switch is open $$(ii)$$ $$S$$ is closed
Questions Asked from Operational Amplifier (Marks 5)
Number in Brackets after Paper Indicates No. of Questions
GATE EE Subjects
Electric Circuits
Electromagnetic Fields
Signals and Systems
Electrical Machines
Engineering Mathematics
General Aptitude
Power System Analysis
Electrical and Electronics Measurement
Analog Electronics
Control Systems
Power Electronics