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

Find the initial current, In the circuit shown below, the capacitor initial...

In the circuit shown below, the capacitor initially has a voltage across it 4 Volts (at t = 0). a.  Write down the expression for V C (t) when the switch is closed. b.  Writ

Difference between div and idiv instructions, Mention how do the DIV & I...

Mention how do the DIV & IDIV instructions differ in their functionality DIV: Unsigned numbers division and IDIV: Signed number division.

Simulate the circuit using digital simulation techniques, You are the new c...

You are the new chief PCB designer for a small company who are about to become heavily involved in the design and realisation of digital timing products. Your management wants to p

Harmonics, how harmonics shows effect on power systems?

how harmonics shows effect on power systems?

A 450 ns eprom won''t work directly with a 5mhz 8088, A 450 ns EPROM won't ...

A 450 ns EPROM won't work directly with a 5MHz 8088.Why? Explain. While the 8088 is operated along with a 5 MHz clock, it permits 460 ns for the memory to access data. Due to t

Illustrate breakpoint analysis, Q. Illustrate Breakpoint Analysis? When...

Q. Illustrate Breakpoint Analysis? When a circuit consists of two or more ideal diodes, it will have several distinct operating conditions resulting from the off and on states

Advantages of software defined radio, Advantages of SDR 1. Easy to upgr...

Advantages of SDR 1. Easy to upgrade 2. Great flexibility. It can be dynamically updated with new software without any changes in hardware 3. Due to reduced number of har

Emitter follwer, Ask questertion #Minimum 100 words accepted#

Ask questertion #Minimum 100 words accepted#

Feedback amplifier, #I want to get lecture notes on Electronic device.and c...

#I want to get lecture notes on Electronic device.and circuits .

What are operations performed on data in 8085, What are operations performe...

What are operations performed on data in 8085 The various operations performed are Store 8-bit data Perform arithmetic and logical operations Test for conditio

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