Explanation: Since the value of high cut- off frequency is mentioned. Consequently, some chips have been getting expensive due to students relying too much on one model and manufacturer. 38) Which Op-amp IC … ELECTRONICS IMPORTANT MCQ PDF 6 FOR BEL PROBATIONARY ENGINEERS EXAM 2017. Determine the values of load current and output voltage respectively for the below schematic of … The Clipping Amplifier Circuit. The Barkhausen criterion for an oscillator. On the other hand, the time required for rising the logic threshold voltage at the output after the driving session of strobe terminal is conducted from zero to one logic level. Objective: To study the working of op-amp … A typical summing amplifier with three input voltages V 1, V 2 and V 3 three input resistors R 1, R 2, R 3 and a feedback resistor R f.; The following analysis is carried out assuming that the op-amp is an ideal … If you are looking for a reviewer in … Resistances of photo-conductive cell are noted along with the corresponding light intensities & then the resistances are expressed in terms of ohm while the light intensities are expressed in terms of meter candles (lux). Harikesh Yadav May 30, 2017 ECE MCQ PDF, General. Loop gain should be unity; Loop gain should be less than unity; The phase of a feedback signal with respect to input should be 0° or 360° The DC Level at the output of intermediate stage is good above ground potential in case of direct coupling. All Rights Reserved. The arrangement of diodes in comparator circuit is in such a way that they play a cardinal role in protecting Op-amp from getting damage due to excess of input voltage. Operational Amplifier : OP-AMP MCQ’s Part 2 Operational Amplifier : OP-AMP MCQ’s Part 2 11. Apart from this advantage, external resistor also possesses a beneficiary notion of increasing the linearity range of differential amplifiers. Explanation: Sensitivity is basically a dimensionless quantity & implies the change in resistance due to change in length of wire at a unity level. MCQ in Microelectronics ; MCQ in Integrated Circuits components ; MCQ in Characteristics and products (ICs) MCQ in Operational Amplifiers ; MCQ in Multivibrators; Start Practice Exam Test Questions Part 1 of the Series. The modern integrated circuit version is typi ed by the famous 741 op-amp. 1. If an input is in the form of a sinusoidal waveform then the output will generate a cosine waveform due to direct relationship of output voltage and negative negative integral of input voltage. If the feedback resistor gets replaced by a capacitor in a basic inverting amplifier, then the integrator circuit can be produced. Explanation: Op-amp ICs varying in the version of 741 are highly approved or sanctioned for military grade since the temperature range lies within -55° to 125°C. Pin Diagram of an Op Amp IC. Hence, they can be sinusoidal if RC components are used while they can be square if LC components are used & even they can be saw-tooth or triangular if crystal oscillator is used. So, it is wide used in low-voltage switching regulators. So, as the … The Following Section consists of Multiple Choice Questions on Basic Op-Amp Circuits. 741 Operational Amplifier Applications. Explanation: Structural Configuration of a differential amplifier is semantic to wheatstone bridge since the amplification is done between two input signals in exactly similar way just like the outputs of Wheatstone bridge network. A bistable multivibrator is a (a) free running oscillator (b) triggered oscillator (c) sawtooth wave generator (d) crystal oscillator Q2. Explanation: Comparator is a circuit which performs comparison between the signal voltage on one input of Op-amp with reference voltage on another input. These short solved questions … Multiple Choice Questions and Answers By Sasmita January 9, 2020 Multiple Choice Questions and Answers on Op-Amp ( Operational Amplifier ) In addition to reading the questions and … Explanation: Op-amp ICs varying in the version of 741 are highly approved or sanctioned for military grade since the temperature range lies within -55° to 125°C. Q.182.For IC 741 typical value of input bias current is—————-(a) 10μA (b) 80nA (c) 1mA (d) 30mA. IC 741 mainly performs mathematical operations like addition, subtraction, division, multiplication, integration, differentiation etc. Since bandwidth is a small signal phenomenon, it represents the band of frequencies for which the gain remains constant & also highly dependable on compensating components including closed loop gain. 33k Ω As we know that Rf should be equal to 0.586 x R1, then R1 = 27k Ω)Thus, Rf = 0.586 x 27 = 15.86k Ω By taking into consideration the pot value of about 20k Ω, estimated resistances are R2 = R3 = 33k Ω C2 = C3 = 0.0047μ F R1 = 27k Ω & Rf = 15.8k Ω Step 4 : Since the values of resistors and capacitors are equal , the passband voltage gain must be equal to Af = 1 + (Rf / R1) 1.586However, the gain must satisfy the Butterworth response & hence, the value of R1 must be selected = 100k Ω in order to estimate the value of Rf. Resolution specifies the number of input bits with the valuation in the form of least significant bit (LSB) whereas the settling time implies the requirement of time for DAC output to settle down between positive or negative ½ LSB of the final value of digital input (which is generally zero to full scale). Hence, both the shortcomings can be resolved by using positive or (regenerative) feedback. An op-amp is a direct coupled high gain … Similar to band-pass filters, band-reject filters also gets classified into wide & narrow band-reject filters. Below enlisted are the steps to evaluate filter components of second order low pass filter for designing purpose.Step 1 : Assume R2 = R3 = R & C1 = C2 = C. Step 2 : Select the value of C = 1μ F Suppose that C1 = C2 = C = 0.0047μ F Step 3 : Determine R by using formula R = 1 / 2 π fH CR2 = R3 = 1 / (2 π x 103 x 47 x 10-10) = 33.86k Ω (consider the round figure value i.e. Multiple Choice Questions and Answers on Oscillators. Q2. Some of the general characteristics of the IC version are : – High gain, on the order of a million – High input imp … Explanation: Photo-conductive cells can be categorized under the family of photo-detectors which shows variation in the resistance due to incidence of light or any other form of radiant energy. The evaluation of the test taken by a candidate will be provided on line after submission of the answer of last question.Duration of The Test- 18 minutes**Note- This test is available only to authorized users.This MCQ is created bySatyajit's ClassesMr. Explanation: Microprocessor interfacing is an application of ADCs while all the remaining applications like microcomputer interfacing, programmable power supply & CRT graphics are the applications concerned to digital to analog converters in accordance to their functionalities. 2: Image showing Output from LM741 OPAMP IC based RC Phase Shift Sine Wave Oscillator on an … Ferrite EI, U & toroid cores exhibits lower performance in the aspects of permeability, high temperature & expensive to greater extent. It is an 8 pin IC. These objective type questions are very important for competitive exams like IIT-JEE, GATE, CAT etc. Explanation: Integrator is basically a circuit where the output voltage forms an integral part of input voltage. Therefore, the voltage difference 'Vref' must be smaller than input voltage. Multiple Choice Questions on Special-Purpose Op-Amp Circuits. Another name of VCO is Voltage to frequency converter.For e.g. For an instance, twin-T network. Explanation: (a) By applying voltage -divider rule, initial voltage at terminal 5 is given by,Vc = (20K) (15) / 11.5K = 26.09 VThus, the frequency of output waveform (nominal frequency) is approximated by,fo ≈ 2(+V - Vc) / R1C1 (+V) = 2 (15 – 10.43) / (20K x 10-9) x (15) = 30.47 kHz (b) Thus, the modulation in the output frequencies can be calculated by initially substituting Vc = 10V & then 11.5 Vfo = 2 (15 – 10) / 20K x 10-9 x 15 = 33.34 kHz fo = 2 (15 – 11.5) / 20K x 10-9 x 15 = 23.34 kHzHence, the variation in an output frequency can be evaluated by the difference between these both frequencies.i.e. Which among the following is a military grade op-amp IC? The most probabilistic approach of hysteresis occurrence can be observed in the comparators with positive (or regenerative) feedback. It is possible to control the current in the heat-generating circuit with an assistance of relay driven by the temperature controller itself. However, this type of transistor array ultimately leads to acquire the thermal stability and the requisite amount of collector current in a current mirror circuit.Due to simplicity in fabrication and operation, current mirror circuit have wide range of applications in the aspects of differential and operational amplifiers. Can we use IC 741 for high frequency applications? Explanation: The type of waveform generation by an oscillator totally depends on components used in the circuit. Q.183.For IC 741 typical value of input offset current is—————- ... ELECTROMAGNETIC FIELD THEORY 69 IMPORTANT EXPECTED MCQ … Temperature indicator is also constructed using thermistor as a transducer with the only difference that output meter is calibrated in degree Celsius or Fahrenheit. Other ICs mentioned in the question are only applicable to certain specific sort of applications other than the military ones. Due to this, they offer maximum stability & predictability but are very expensive similar to that of ferrite EI, U & toroid cores. Powdered permalloy toroids possess are highly permeable with lower values of leakage inductance & losses. Signetics NE/SE 566 VCO generates the triangular as well as square wave outputs simultaneously as a function of an input voltage. Q1. Jobs in Pakistan, Karachi, … All the mentioned parameters tend to infinity except output voltage & resistance so that it becomes feasible for an output to drive infinite number of other devices. Explanation: Silicon steel EI butt stack method shows better permeability & high flux density along with the simplicity in construction phase. Besides these, 741S & 741SC are recommended for military as well as commercial aspects due to high slew rate. ANSWER: Adjusted Output from signal amplifier is directly proportional to the measured quantity. IC LF 398 forms a leading part of sample & hold circuit while IC LM117 can be used as a switching regulator & also provides full overload protection to other ICs. ANSWER: R2, R3 = 33k Ω, C1 = C2 = 0.0047μ F, R1 = 27k Ω & Rf = 15.8k Ω. These narrow band-reject filters are widely used for single frequency rejection like 60 Hz power line frequency hum. This set of Linear Integrated Circuit Multiple Choice Questions & Answers (MCQs) focuses on “Ideal Operational Amplifier”. Hence, this is the major drawback because of which it is highly impossible to use Op-amps with open loop configurations in linear circuit applications. Explanation: For non-inverting mode of an amplifier (voltage series feedback amplifier) 1) Af = AB / 1 + ABBut, B = R1 / (R1 + Rf) = 2 k / (2 k + 20 k) = 1 / 111 + AB = 1 + 400000 x (1 / 11) = 36364.6 Af = 400000 / 3636.4 = 10.99 2) fF = (1 + AB) fo = (36364.6) x 10Hz = 363646 = 36.36 KHz. Eventually, the parameter of settling time is totally not involved in comparators. Explanation: Corresponding to the manufacturers own productivity of ICs, they also go for the production of one another's renowned ICs. For an instance, Op-amp 741 is originally developed by Fairchild but it also gets manufactured by different number of manufacturers under the category of their own designations. Capacitor discharge interval in monostable circuits is known as (a) refresh time (b) recovery time (c) dynamic time (d) static time Q3. ANSWER: Unit change in R per unit change in 'l'. As a result, this external resistor is also renowned as 'Swamping Resistor' because of its swamping strategy. ... c. IC LM 117 d. IC 741. A waveform generator is an electronic circuit, which generates a standard wave. … Explanation: Temperature control circuit can be built up by using a thermistor in bridge circuit along with the replacement of a meter by a relay in the structural configuration of differential instrumentation amplifier. Basically, each input voltage gets amplified by a different factor & then weighted differently at the output level. Despite bridge circuits, light-intensity meter can be built-up by using a photocell as a transducer while two thermistors are adjacently connected in thermal conductivity meter circuits. This entire functionality is undertaken by Voltage -Controlled Oscillator (VCO). The op amp IC we are going to discuss about here is IC 741. Hence, this scaling amplifier is also referred as 'Weighted Amplifier'. When the difference of … Explanation: Non-inverting amplifier has greater output voltage than that of its input voltage & is in phase with it. This input voltage performs the functionality of controlling voltage level & hence, precisely referred as 'Control Voltage'. Explanation: All-pass filters allows to pass all the frequency components of input signal without any attenuation by anticipating phase shifts for different frequencies. Explanation: The thermal drift phenomenon of voltage & current are taken into consideration in accordance to the values of input offset voltage, input bias current & input offset current. Thus, when the input value falls below lower threshold voltage, then the output gets returned to its original position or state +Vsat. The transient response affects the settling time while slew rate give rise to distortion if exceeded. ANSWER: Reference voltage must be less than input voltage. On the contrary, the output voltage of inverting Op-amp goes out of phase in correspondence to input signal by an angle of 180° or in terms of opposite polarity. What are differential gain and common-mode gain of a differential amplifier? But, in some of the applications like Frequency Modulation (FM), Frequency Shift Keying (FSK) where the frequency needs to be controlled by input voltage. 15. However, response & conversion time are not the valid specifications for DAC selection since they are of significant importance in ADC. Narrow band-reject filter is commonly known as notch filter since it has high quality factor (Q>10) & bandwidth is very much smaller as compared to that of wide band-reject filters. Several drawbacks related to performance characteristics were highlighted like no protection to short circuits, latch-up problem and absence of external frequency-compensating network for stable operation. Output of Delay Equalizers can be generated by using Super-position theorem. 33.34 - 23.34 = 10 kHz. The number 741 indicates that this operational amplifier IC … However, these diodes are also called as 'Clamp Diodes'. Therefore, quality factor is a measure of selectivity which infers that the selectivity of the filter depends on the value of 'Q'. No, IC741 has a low slew rate. Frequency Scaling is most oftenly performed whenever there is a necessity to change the cut-off frequencies in filter designing process. There are two types of op-amp based waveform generators − Square wave generator; Triangular wave generator; This … Even if we used as a comparator the IC still observes the weak signals so t… However, variations in these parameters ultimately changes the level of thermal drift (Drift voltage & Drift current). Explanation: Generally, the time constant helps in determining the frequency of oscillation in any oscillator. But, it exhibits adverse consequences in the reduction of an output voltage when exceeded to greater extent. This figure of merit conveys that if 'Q' > 10, the filter is considered to be a narrow band-pass filter whereas if 'Q' < 10, then the filter is considered as a narrow band-pass filter. Due to this configuration, the dependability of voltage gain which varies in accordance to changes in emitter resistance can be ablated. IC 741 has three stages such as differential input, gain, … Higher the value of quality factor, more is the selectivity of the filter. Explanation: Offset minimizing resistors are the only means of reducing the amount of output offset voltage. Due to this reason, the output gets switched between the positive and negative saturation levels. ANSWER: IC 741. For use in various applications, In different ways. Fig. The integrated circuit … Explanation: External resistor of a differential amplifier is connected in series combination with each emitter. All Rights Reserved. Intuitively, sensitivity measures the degree of accuracy & resolution. Educational Learning Point having all the articles of multiple subjects/area e.g; Computer Science, Medical, General Knowledge, Law, English, Islamic studies and Others. Explanation: Given data:Voltage Peak Value = 7mVFrequency = f = 1KHzR = 1500K Ω C = 2μF = 2 x 10-6 FAn input voltage equation of a differentiator circuit can be expressed by, V1 = Asin2 πft= 7 sin2π x 1000 t= 7 sin2000π t mVScale Factor = -CR = - [2 x 10-6 x 15 x 105] = - [30 x 10-1 ] = -3Hence, the output voltage of differentiator circuit can be evaluated as:Vo = -3 d / dt [7 sin 2000 π t]= -3 x 7 x 2000 cos 2000 π t= -42000 π cos 2000 π t mV. Here, the frequency gets converted & not deviated or translated or divided before the conversion process. Also, the noise at the op-amp input terminals may fluctuate the output between positive & negative (+Vsat & -Vsat) saturation voltages. However, the value of external resistor has an efficiently high value to swamp the consequences of emitter resistor of amplifier. Explanation: Narrow & Wide band-pass filters can be distinguished only on the basis of quality factor. Explanation: Hysteresis phenomenon is a dead-band condition where the output switches from +Vsat to -Vsat whenever input value becomes greater than the upper threshold voltage. a) Explain IC 741 along with its Pin Diagram and ideal Characteristics of Op-amp. The 741 … In addition to reading the questions and answers on my site, I would suggest you to check the following, on amazon, as well: … Operational Amplifier, also called as an Op-Amp, is an integrated circuit, which can be used to perform various linear, non-linear, and mathematical operations. The voltage gain of IC 741 is about a. Apart from this, average circuit produces the output voltage by considering the average of all input voltages. This can only be possible when all input resistances belong to the different values. The popular IC 741 … Which are interchanged between the positive value and negative value, hence this is the one way of presenting the common emitter amplifier circuit to function between two peak values. Materials like cadmium sulphide and silicon are used for photo conductive cells to greater extent since their conductivity is a function of incident radiant energy. Set 1; Set 2 ) Post navigation. The significant advantage of hysteresis is that it increases the speed of operation of the comparator. In case of non-inverting amplifier, the input is applied to non-inverting input terminal & inverting terminal is set to be grounded while in case of inverting amplifier, the input is applied to inverting terminal & non-inverting terminal is at ground level.