Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. Write a short note on the working of Darlington Amplifier?
A Darlington Amplifier is one that is employing the Darlington pair of transistors. It is a cascaded emitter follower circuit.
The arrangement is such that the first transistor's emitter is connected to the base of the second transistor. Further the two collectors are tied together and are connected to the collector supply. Thus the second transistor forms the load impedance of the first amplifier.
Assuming that the ‘h' parameters of the two transistors, Q1 and Q2 are the same, it can be shown that the voltage gain of the Darlington stage is less than unity. The input resistance of the complete Darlington Emitter Follower Circuit is much higher than the input resistance of the emitter follower circuit. The output resstance will be low.
The input signal varies the base current of the first transistor. This produces the variation in the collector current in the first transistor. The emitter load of the first stage is the input resistance of the second stage. The emitter current of the first transistor is the base current of the second transistor.
The circuit is therefore a cascade of two emitter followers. Hence the gain is less than the gain of the emitter follower circuit which is less than unity. To provide a reasonable operating current in the first stage the second stage should be a power stage.
Q. Fixed Voltage Regulators ? Positive voltage regulator series with seven voltage options - IC 7800 Series The 7800 series consists of three - terminal positive volta
Q. A 10-kW, 250-V dc shunt generator, having an armature resistance of 0.1and a field resistance of 250 , delivers full load at rated voltage and 800 r/min. The machine is now ru
Q. A dc shunt machine has an armature winding resistance of 0.12 and a shunt-?eld winding resistance of 50 . The machine may be run on 250-V mains as either a generator or a mot
Q. Explain how LEDs are arranged in a seven segment display ? The illustration given below shows the basic layout of the segments in a seven- segment display. The segments the
the forward resisitance of a semi conductor diode is 10 ohm, two such diodes used in full wave rectifier subjectto a sinusoidal voltage wave form. given by v(t)=308 , sin(100 pi t)
(a) Consider the following transmission line with the reactance X1 placed across the input. It is being driven with a frequency ω such that the length of the line is λ/4. What v
Question 1: a) Describe how pipelining can improves the efficiency of the fetch-execute cycle. b) Explain the term superscalar architecture. c) Explain the term prin
Q For a parallel-plate capacitor with plates of area A m 2 and separation d m in air, the capacitance in farads may be computed from the approximate relation Compute the a
To convert a galvanometer to a voltmeter, you should add a: a) High resistance in series b) High resistance in parallel c) Low resistance in series d) Low resis
Disadvantages
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd