What is a darlington pair, Electrical Engineering

Assignment Help:

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.

1806_What is a darlington pair.png

 

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.


Related Discussions:- What is a darlington pair

History of transistor, History of Transistor: The great Physicist Juli...

History of Transistor: The great Physicist Julius Edgar Lilienfeld filed the first patent for a transistor in Canada in the year 1925, explaining a device identical to a Field

Sectoral overview and enabling framework, Sectoral Overview and Enabling Fr...

Sectoral Overview and Enabling Framework Previously, you have studied about several Acts and Policies relevant to the power sector, their aims, main features and implications

When mt2 is negative and g is positive , When MT 2 is Negative  and g is ...

When MT 2 is Negative  and g is positive In this  case  gate  current  flows  through  junctions P 2 N 2   electrons  are injected from  N 2   layer to  P 2   a result  junct

MUX, Is it used to replace the basic gates ?

Is it used to replace the basic gates ?

transmisson medium, Can I find out the salution of electrods Transmissio...

Can I find out the salution of electrods Transmission medium light sound uncoupling magnet for high dc cycle. I need to purches an electromagnet of this sort can you Please assis

Explain how leds are arranged in a seven segment display, Q. Explain how LE...

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

Short-term measures for technical loss reduction, Short-Term Measures for T...

Short-Term Measures for Technical Loss Reduction The short-term measures involve measures needs for immediate improvement and reduction of losses within the system. These are

Effective mass, Effective Mass The electrons' "wave-particle" motio...

Effective Mass The electrons' "wave-particle" motion in a lattice is not the same as that for a free electron, because of the interaction with the periodic potential of the

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd