Circuits Q&A: My Question About Vdb

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In summary, Vdb, or voltage drop across the base-emitter junction, is an important parameter in circuits that use transistors. It can be calculated using Ohm's Law, and it is crucial in circuit design as it affects the performance of a transistor. Various factors can affect Vdb, including temperature and biasing current, and it can be controlled through proper biasing techniques and transistor selection. It is important to consider these factors during circuit design to achieve desired Vdb values.
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Miike012
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My question is regarding Vdb.
for pos flow of charge

Vbd = -Vdb
and
Vdb = -VR2
so Vbd = VR2.

This means that the current flowing from point d to point b gained potential energy. However the flow of charge from d to b are electrons and electrons lose potential energy as they move from lower to higher potentials. So when I look at it in that point of view
Vbd should be equal to -VR2.

Can someone clarify to me why I am wrong.
 

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Electrons are negatively charged, and flow in the opposite direction of the current.
 

1. What is Vdb in circuits?

Vdb, or voltage drop across the base-emitter junction, is an important parameter in circuits that use transistors. It represents the amount of voltage that is dropped across the base-emitter junction when a current flows through it.

2. How is Vdb calculated?

Vdb can be calculated using Ohm's Law, which states that V=IR, where V is voltage, I is current, and R is resistance. In the case of a transistor, Vdb is equal to the base current (Ib) multiplied by the base-emitter resistance (Rbe).

3. Why is Vdb important in circuit design?

Vdb is important because it affects the performance of a transistor in a circuit. A higher Vdb can cause the transistor to operate in a less efficient region, leading to increased power dissipation and potential circuit failure. It is important to design circuits with appropriate Vdb values to ensure proper functioning.

4. What factors can affect Vdb?

Vdb can be affected by various factors, including temperature, biasing current, and transistor characteristics. As temperature increases, Vdb also tends to increase. A higher biasing current can also lead to a higher Vdb. Additionally, different types of transistors can have different Vdb values due to their unique characteristics.

5. How can Vdb be controlled in a circuit?

Vdb can be controlled by using proper biasing techniques, such as using a resistor in series with the base-emitter junction to limit the current flow. Additionally, selecting a transistor with a lower base-emitter resistance can also help to control Vdb. It is important to consider these factors during circuit design to achieve desired Vdb values.

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