Which of the following is the correct relationship between base and emitter current of a BJT

The relationship between the base current (Ib) and the emitter current (Ie) in a Bipolar Junction Transistor (BJT) is given by the formula:

Ie = Ib + Ic

Where:

• Ie is the emitter current
• Ib is the base current
• Ic is the collector current

This relationship is based on the principle of conservation of charge because the emitter current is the sum of the base and collector currents.

In a typical active mode operation of a BJT, the base current Ib is much smaller than the collector current Ic. Therefore, the emitter current Ie is approximately equal to the collector current Ic.

However, the exact relationship between Ib and Ie depends on the transistor's beta (β) or current gain, which is the ratio of the collector current to the base current (β = Ic/Ib).

So, if you know the value of β, you can calculate Ib from Ic or vice versa using the formula:

Ib = Ic / β

Then, you can find Ie using the first formula:

Ie = Ib + Ic

So, the relationship between the base and emitter current of a BJT is determined by the transistor's current gain and the collector current.