Description : Mention some of the linear applications of op – amps.
Last Answer : Adder, subtractor, voltage –to- current converter, current –to- voltage converters, instrumentation amplifier, analog computation ,power amplifier, etc are some of the linear opamp circuits.
Description : Why open loop OP-AMP configurations are not used in linear applications?
Last Answer : The open loop gain of the op-amp is not a constant and it varies with changing the temperature and variations in power supply.Also the bandwidth of the open loop op-amp is negligibly small.For this reasons open loop OP-AMP configurations are not used in linear applications.
Description : How frequency to voltage converted on OP-AMPS.
Last Answer : A Frequency to voltage converter produces an output voltage, whose amplitude is a function of frequency of the input signal. The input signal may be a sinewave, a square wave or a pulse train. The F/V converter is essentially an FM detector or discriminator.
Description : What is the need for frequency compensation in practical op-amps?
Last Answer : Frequency compensation is needed when large bandwidth and lower closed loop gain is desired. Compensating networks are used to control the phase shift and hence to improve the stability.
Description : In practical op-amps, what is the effect of high frequency on its performance?
Last Answer : The open-loop gain of op-amp decreases at higher frequencies due to the presence of parasitic capacitance. The closed-loop gain increases at higher frequencies and leads to instability.
Description : What are the areas of application of non-linear op- amp circuits?
Last Answer : 1. Industrial instrumentation 2. Communication 3. Signal processing
Description : Draw the circuit diagram for Instrumentation amplifier using three OP-AMPs. State its advantages and applications.
Last Answer : Application: 1. In Data acquisition from low output transducers such as strain gauges, Thermocouples, Wheatstone bridge measurements e.t.c 2. In Medical instrumentation, Navigation, Radar ... video data acquisition and imaging 5. High frequency signal amplification in cable RF systems
Description : The three devices which make up the circuit shown in the illustration are ____________. EL-0087 A. flip-flops B. exclusive 'OR' gates C. summing op amps D. function generators
Last Answer : Answer: A
Description : An OP-AMPs can amplify _______ (a) D.C (b) A.C (c) both A.C & D.C (d) none of above
Last Answer : b) A.C
Last Answer : 1
Last Answer : Op amp is operational amplifier. Operational amplifier are use in ADC, zero crossing detector ,DAC, filters, Voltage regulators, Current regulators, etc.
Description : Mention some applications of 555 timer
Last Answer : *Oscillator *pulse generator *ramp and square wave generator *mono-shot multivibrator *burglar alarm *traffic light control.
Description : Mention some typical applications of PLL
Last Answer : • Frequency multiplication/division • Frequency translation • AM detection • FM demodulation • FSK demodulation.
Description : What is the type of feedback used in an op-amp Schmitt trigger?
Last Answer : The type of feedback used in an op-amp Schmitt trigger is positive feedback.
Description : What is the basic building block of an op-amp?
Last Answer : The basic building block of an op-amp is differential amplifier.
Description : What is the type of feedback employed in the inverting op-amp amplifier?
Last Answer : Negative feedback is employed in the inverting op-amp amplifier.
Description : What are the DC characteristics of an op-amp?
Last Answer : a. input bias current b. Input offset current c .Input offset voltage d. Thermal drift
Description : What are the AC characteristics of an op-amp?
Last Answer : a. Frequency response b. Slew rate
Description : What is compensated op-amp?
Last Answer : Op-amp, which uses a capacitor internally for compensation, is called a compensated op-amp. This op-amp has a high gain stability and low bandwidth.
Description : What is an op-amp?
Last Answer : The operational amplifier is a multi-terminal device, which is quite complex internally. An operational amplifier is a direct coupled high gain amplifier usually consisting of one or more ... as well as ac input signals and was originally designed for computing such mathematical functions.
Description : Write transfer function of op amp as an integer.
Last Answer : The transfer function of the integer is LAL=1/MR1cf
Description : Define CMRR of an op-amp.
Last Answer : The relative sensitivity of an op-amp to a difference signal as compared to a common – mode signal is called the common –mode rejection ratio. It is expressed in decibels. CMRR= Ad/Ac
Description : Define input offset current. State the reasons for the offset currents at the input of the op-amp.
Last Answer : The difference between the bias currents at the input terminals of the op-amp is called as input offset current. The input terminals conduct a small value of dc current to bias the input transistors.Since the input transistors cannot be made identical,there exists a difference in bias currents.
Description : Define virtual ground of a OP-Amp?
Last Answer : A virtual ground is a ground which acts like a ground. It is a point that is at the fixed ground potential (0v),though it is not practically connected to the actual ground or common terminal of the circuit.
Description : The speech coding rate in D-AMPS is ____. A. 8 kbps B. 13 kbps C. 15 kbps D. 20 kbps
Last Answer : A. 8 kbps
Description : Which of the following systems uses frequency band 870-885 MHz as a transmit band of its base station? A. TACS B. NTT C. NMT D. AMPS
Last Answer : B. NTT
Description : Write the specifications of linear and non- linear potentiometers. State its applications
Last Answer : Specifications of linear & nonlinear potentiometers: 1. Ohmic range: 10Ω to 125 kΩ 2. Power rating : 100watt to 200 watt 3. Tolerance : 2% 4. Voltage Rating: 5V-500V 5. Operating ... 7. Used as potential dividers. 8. It is used for panel control in receivers, function generator etc
Description : In a triple conversion superheterodyne receiver, diode mixer stages are operated A. In the linear region B. In the nonlinear region C. As class A amplifiers D. As class B amplifiers
Last Answer : B. In the nonlinear region
Description : What is the meaning of forward power? A. The power traveling from the transmitter to the antenna. B. The power radiated from the top of an antenna system. C. The power produced during the positive half of an RF cycle. D. The power used to drive a linear amplifier.
Last Answer : A. The power traveling from the transmitter to the antenna.
Description : Give the drawbacks of linear regulators:
Last Answer : *The input step down transformer is bulky and expensive because of low line frequency. *Because of low line frequency,large values of filter capacitors are required to decrease the ripple. * ... reduced due to the continous power dissipation by the transistor as it operates in the linear region
Description : What is a linear voltage regulator?
Last Answer : Series or linear regulator uses a power transistor connected in series between the unregulated dc input and the load and it conducts in the linear region .The output voltage is controlled by the continous voltage drop taking place across the series pass transistor.
Description : Write some applications of PN junction diode
Last Answer : 1. Rectifier circuit ii. clipping and clamping iii voltage multiplier iv AM detection v. Feedback diodes vi Freewheeling diode
Description : What type of balun (balanced-to-unbalanced) is used in high frequency applications? A. Transformer type balun B. A specially configured coaxial transmission line C. A specially configured parallel-wire line D. A λ/2 transformer balun
Last Answer : B. A specially configured coaxial transmission line
Description : List the applications of instrumentation amplifier.
Last Answer : a. Temperature indicator b. Temperature controller c. Light intensity meters d. Water flow meter c. Thermal conductivity meter f. Analog weight scale
Description : List the applications of 555 timer in Astable mode of operation
Last Answer : *FSK generator *Pulse-position modulator
Description : List the applications of 555 timer in monostable mode of operation
Last Answer : *missing pulse detector *Linear ramp generator *Frequency divider *Pulse width modulation.
Description : What are the applications of comparator?
Last Answer : 1.Zero crossing detector 2.Window detector 3.Time marker generator 4.Phase detector
Description : List the applications of Log amplifiers:
Last Answer : 1.Analog computation may require functions such as lnx, log x, sin hx etc. These functions can be performed by log amplifiers 2.Log amplifier can perform direct dB display on digital voltmeter and spectrum analyzer 3.Log amplifier can be used to compress the dynamic range of a signal
Description : Write down the applications of precision diode.
Last Answer : 1.Half - wave rectifier 2.Full - Wave rectifier 3.Peak – value detector 4.Clipper 5.Clamper
Description : What are the applications of V-I converter?
Last Answer : 1.Low voltage dc and ac voltmeter 2.L E D 3.Zener diode tester
Description : Why IC 741 is not used for high frequency applications?
Last Answer : IC741 has a low slew rate because of the predominance of capacitance present in the circuit at higher frequencies. As frequency increases the output gets distorted due to limited slew rate.
Description : What are the applications of current sources?
Last Answer : Transistor current sources are widely used in analog ICs both as biasing elements and as load devices for amplifier stages.
Description : Mention some areas where PLL is widely used.
Last Answer : 1.Radar synchronizations 2. Satellite communication systems 3. Air borne navigational systems 4. FM communication systems 5.Computers.
Description : Define Multivibrators. Mention its types.
Last Answer : Multivibrators are regenerative circuits, Which are mainly used in timing applications. Based on their operational characteristics they can be classified into • Astable Multivibrators • Monostable Multivibrators • Bistable Multivibrators
Description : Mention the advantages of opto-couplers:
Last Answer : *Better isolation between the two stages. *Impedance problem between the stages is eliminated. *Wide frequency response. *Easily interfaced with digital circuit. *Compact and light weight. *Problems such as noise, transients, contact bounce,.. are eliminated.
Description : Mention any two audio frequency oscillators .
Last Answer : i. RC phase shift oscillator ii. Wein bridge oscillator
Description : Mention the advantages of Wilson current source.
Last Answer : (i) Provides high output resistance. (ii) Offers low sensitivity to transistor base currents.
Description : Mention the advantages of integrated circuits over discrete components.
Last Answer : *Miniaturisation and hence increased equipment density. *Cost reduction due to batch processing. *Increased system reliability due to the elimination of soldered joints. *Improved functional performance. *Matched devices. *Increased operating speeds. *Reduction in power consumption.
Description : As long as op-amp is not saturated, the potential difference between inverting and non-inverting inputs is A. zero B. infinite C. 1 D. 2
Last Answer : zero
Description : Why are the 2 input terminals of an op-amp are called as inverting & non-inverting terminals?
Last Answer : Ans-Because if we give input to one input means that will produce the same phase output where as the other(Inverting) pin produce 180 degree phase shifted output.