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. What is a darlington pair?
The Darlington circuit consists of two cascaded emitter followers with infinite emitter resistance in the first stage.here the two transistor form a composite pair, input impedance of the second transistor consisting of the emitter load resistance of the first transistor.
· Darlington emitter follower has high input impedance than the single stage emitter follower.
· Its voltage gain is less close to unity than a single stage emitter follower.
· The output impedance of a darlington circuit may be greater than or less than that of a single transistor emitter follower, depending upon the value of resistance.
· Major drawback of Darlington transistor pair is that the leakage current of the first transistor is amplified by the second; hence the overall leakage current is high. A Darlington pair is two transistors connected together to give a very high current gain. In addition to standard (bipolar junction) transistors, there are field-effect transistors which are usually referred to as FETs.
The emitter current of Tr1 is the base current of Tr2.
A change in base current of Tr1 can give a change 100 times larger in its emitter current. A change in the base current of Tr2 has a similar effect on its emitter current. Therefore there is an overall amplification of 100 x 100 = 10000 times. This circuit is sometimes called the Super Alpha Pair. It is often used as a power output stage.
Q. Explain workinf of colpitts oscillator? When the collector supply voltage V cc is switched on, the capacitors C1 and Cz are charged. These capacitors C1 and Cz discharge thr
A 100-kW, dc shunt generator, connected to a 220-V main, is belt-driven at 300 r/min, when the belt suddenly breaks and the machine continues to run as a motor, taking 10 kW from t
The circuit shown below is a prototype 4 th - order low-pass filter which is required to meet the specification given. However the specification is not met due to inadequate atten
Q. Advantages of subscriber loops signalling? (i) Information can be exchange between processors much more faster than when channel associated signalling is used. (ii) As a
An electromechanical voltmeter with internal resistance of 1 k and an electronic voltmeter with internal resistance of 10 M are used separately to measure the potential differenc
Particles of mass M and m separated in space by a distance R exert a mutually attractive gravitational force F on one another given by where G is the universal gravitationa
3-phase 120 0 Mode VSI In 1200 mode VSI each thyristor conducts for 1200. At a time only thyristor one form upper group and another form group will conduct. Only th
Given: R 1 = R 3 = 1 k_, R 2 = 100 k_ and k = 0.1 A/V, and step-up transformer turns ratio is 10. a) Find the value of the load resistor RL that would maximize the power
Q. Define Memory For a digital computer? For a digital computer which stores both programs and data, memory can be divided into three types: random-access memory, mass storage,
Fixed bias (base bias): Diagram: Fixed bias (Base bias) This type of biasing is also known as base bias . In the instance above figure, the single power source (
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