WorksheetsOpamp Basic Questions
Total questions: 33
Worksheet time: 33mins
Determine the output voltage from the following circuit diagram?
How will be the output voltage obtained for an ideal op-amp?
Amplifies the difference between the two input voltages
Amplifies individual voltages input voltages
Amplifies products of two input voltage
The signal to an inverting terminal of an ideal op-amp is zero. Find the output voltage, if the other input voltage is ( see Figure above).
Which is NOT the ideal characteristic of an op-amp?
Input Resistance –> 0
Output impedance –> 0
Bandwidth –> ∞
Open loop voltage gain –> ∞
Open loop op-amp configuration has
Direct network between output and input terminals
No connection between output and feedback network
No connection between input and feedback network
What sort of amplifier is this?
Summing amplifier
Voltage follower
Inverting amplifier
Non-inverting amplifier
If the input of this circuit Vin = 6V what is Vout?
+6 V
-6 V
+12 V
-12 V
0
The common-mode gain is ………..
very high
very low
always unity
unpredictable
The differential gain is ………
very high
very low
dependent on input voltage
about 100
For an Op-amp with negative feedback, the output is …….
equal to the input
increased
fed back to the inverting input
fed back to the noninverting input
The Op-amp can amplify
a.c. signals only
d.c. signals only
both a.c. and d.c. signals
neither d.c. nor a.c. signals
Choose the correct answer of Op-Amp properties.
Infinite Output Impedance
Low Input Impedance
Infinite Open-Loop Gain
Zero Bandwidth
What is the output resistance of an ideal op-amp?
0
Infinity
1
1000
Identify the circuit
Inverting amplifier
voltage follower
Differential amplifier
Non inverting amplifier
What is the input resistance of an ideal op-amp?
0
Infinity
1
1000
Another name for a unity gain amplifier is__________
difference amplifier
comparator
single ended
voltage follower
what is the formula of gain (Av) for Opamp based Non Inverting Amplifier?
-Rf/Rin
-Rin/Rf
1+(Rf/Rin)
1-(Rf/Rin)
The gain equation of inverting amplifier is________
R1/Rf
Rf/R1
-Rf/R1
-R1/Rf
The ideal OP-AMP has the following characteristics.
Ri=∞ ,A=∞ ,R0=0
Ri=0 ,A=∞ ,R0=0
Ri=∞ ,A=∞ ,R0=∞
Ri=0 ,A=∞ ,R0=∞
Identify the one, which is not the DC characteristics of OP AMP
Input bias current
Input offset current
CMRR
Bias voltage
If ground is applied to the (+) terminal of an inverting op-amp, the (–) terminal will:
not need an input resisto
be virtual ground
have high reverse current
not invert the signal
What is the output voltage?
50v
5v
-5v
-50v
Open loop gain of an amplifier can be represented by the formula
Vo/Vi
Vo + Vi
Vo - Vi
Vo × Vi
Ideally, how much current should flow into the input terminals of an op-amp?
Maximum current
Minimum current
No current
Average current
What is input offset current?
a) The average of the two input bias currents
The difference between the two input bias currents
The sum of the two input bias currents
The product of the two input bias currents
Input bias current is defined as
Average of two input bias current
Summing of two input bias current
Difference of two input bias current
Product of two input bias current
Which factor affect the input offset voltage, bias current and input offset current in an op-amp
a) Change in temperature
Change in supply voltage
Change in time
All of the mentioned
Offset current for BJT opamp is
200nA
500nA
100nA
300nA
Offset current for FET opamp is
200nA
10pA
10nA
200pA
input bias current for BJT opamp is
500nA
500pA
50nA
50pA
input bias current for FET opamp is
500nA
500pA
50nA
50pA
CMRR formula is
|Adm/Acm|
|Acm/Adm|
|Adm/2|
|1/Acm|
IC 741 Minimum CMRR value is
70dB
80dB
90dB
170dB
