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Why do we use Darlington pair?

Why do we use Darlington pair?

The Darlington Pair offers a number of advantages. It is primarily used because it offers a particularly high current gain and this also reflects into a high input impedance for the overall Darlington circuit when compared to a single transistor.

How does a Darlington array work?

A Darlington Pair acts as one transistor but with a current gain that equals: Total current gain (hFE total) = current gain of transistor 1 (hFE t1) x current gain of transistor 2 (hFE t2) So for example if you had two transistors with a current gain (hFE) = 100: (hFE total) = 100 x 100 (hFE total) = 10,000 You can see …

Which of the following is a Darlington pair?

A Darlington pair is a two-transistor circuit with the emitter of one transistor is connected to the base of other transistors, while both collector terminals are connected to the common terminal. It has high current gain β; (equal to the product of current gain of individual transistors)

How do you make a Darlington pair?

Darlington Transistor Example: A 60W load with 15V input voltage needs to be switched using two NPN transistors, creating a Darlington pair. The first Transistor gain will be 30 and the second transistor gain will be 95. We will calculate the base current for switching the load.

How do you make a Darlington transistor?

How do Darlington transistors work?

A Darlington transistor acts as a single transistor with high current gain, it means that a small amount of current is used from a microcontroller or a sensor to run a larger load. The below Darlington circuit is built with two transistors shown in the circuit diagram.

What are Darlington arrays used for?

Applications. Darlington pairs are often used in the push-pull output stages of the power audio amplifiers that drive most sound systems.

What is a Darlington array?

The Darlington transistor is a compound structure consisting of two bipolar transistors connected in such a way that the current amplified by the first transistor is amplified further by the second one. Microsemi’s integrated Darlington transistors come packaged singly as an array of devices (eight or seven) in an IC.

What two components make the Darlington pair?

A Darlington pair consists of two npn transistors connected as shown in the diagram. The way they work is easier to understand if it is explained in terms of conventional current. Given a small base current flowing to Q1, a much larger collector current flows into the transistor and out of the emitter.

What are the characteristics of a Darlington pair?

The Darlington pair has many positive characteristics. Some of the main Darlington pair characteristics and parameters are outlines below: High current gain: It has already been seen that the current gain from the Darlington is very high. Figures in excess of several thousand are often seen.

How does a Darlington pair of transistors work?

This transistor is also called as a Darlington pair, contains of two BJTs that are connected to deliver a high current gain from a low base current. In this transistor, the emitter of the i/p transistor is connected to the o/p of the base of the transistor and the collectors of the transistor are wired together.

What is the current gain of a Darlington pair circuit?

This means that if two transistors with modest current gains of 50 were used, then the overall current gain would be 50 x 50 = 2500. Although the Darlington pair circuit is often used in its basic format, it is often seen with a bypass resistor between the base and emitter connections of the final transistor.

Why is the leakage current high in the Darlington pair?

The overall leakage current is high because the leakage current of the first transistor is amplified by the next transistor. That’s why the three or more stages of Darlington is impossible. Hence, the Darlington pair is very useful in most of the application because it provides high current gain at low base currents.