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Biasing problem in Darlington pair

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darlington pair amplifier

Dear all,
Can anyone tell me what is the biasing problem in Darlington pair amplifier?
 

complementary darlington pair

I mean to say when we want to bias the darlington pair amplifier, what problems do we face with?
 

darlington vs sziklai

darlington pair is like a high gain transistor with twice the Vbe drop... so we would have to worry about the 2Vbe voltage required to turn it off... also we have to take care of turning on of the second transistor due to the leakage in the first transistor...
 

darlington biasing

Is there any thing that we can do to solve this problem?
 

diagnosing darlington transistor problems

I thinks we can not just connect the emitter of the first stage to the base of the second stage without connecting a resistor from the emitter of the first stage to the emitter of the second stage. With this resistor connection, there is no leakage problem due to the first stage.

There is a complex poles introduced by the darlington pairs, that may make compensation slightly more complex if you are designing an opamp.

Headroom of 2vbe is the by-products of the darlington pair, we can not do anythng on this, just to have enough Vcc.
 

darlington pair vbe

you can avoid the leakage problem by using a resistor between the emitter and base of the second transistor because the leakage even though can turn the transistor cannot satisfy the Vbe drop to be produced across the transistor due to the extreme low value of the leakage current...

to avoid the 2Vbe required to turn on the transistor you can go for the sziklai or complementary darlington connection....

Regards...
 

how to bias a darlington

the first transistor should have enough drive capality.
 

darlington pair design

wolf001 said:
the first transistor should have enough drive capality.
Click to expand...

what do you mean by saying the first transistor should have enough drive capability because it is just going to drive the base of another transistor using its emitter.... where does drive capability come in there??/
 

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