The name transistor comes from the phrase “transferring an electrical signal across a resistor.”
In this EduRev document, we will discuss two types of transistors:
BJT Schematic Symbols (Mnemonics for remembering the direction of the arrows are in
parenthesis.)
Ohmmeters view of the BJT. Clearly a transistor cannot be made on the bench by combining two resistors. (Why is that?) Most ohmmeters can not only measure the resistance, but also measure the forward voltage drop across a diode. From this perspective you can identify the base and the type of transistor based on the following equivalent circuits.
The output impedance seen by the load (RE in this example) is defined as:
The minus sign in the derivative comes from the fact the output impedance has the effect of decreasing Vout. The output current Iout is just the emitter current IE which is related to the base current.
Thus we obtain the result that the impedance of the source, as viewed by the load, is reduced by the factor ~1/β.
This topic does not end here. So, to read further the topic of FET, click here
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1. What are the different regions of operation for a Bipolar Junction Transistor (BJT)? |
2. What are the rules for Bipolar Junction Transistors (BJTs)? |
3. What are the basic equations for a Bipolar Junction Transistor (BJT)? |
4. What are the different types of amplifiers that can be built using Bipolar Junction Transistors (BJTs)? |
5. What is the input impedance of a Bipolar Junction Transistor (BJT)? |
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