# Question: problem 2 40 points for the commonbase amplifier cb...

###### Question details

**Problem # 2:**

(40 points)

For the common-base amplifier (C.B.) in figure 2, characterized
by a BJT with **β _{dc} =90**, determine:

a. The emitter-current **I _{E}** and the
base-current

**I**

_{B}b. The collector-emitter voltage
**V _{CE}**

c. The collector-base voltage
**V _{CB}**

d. Sketch the **AC** equivalent circuit, using the
**r _{e} model** for the common-base BJT,
and

determine: The input impedance
**Z _{i}**, the output impedance

**Z**, assuming

_{o}**r**and the open-

_{o}= ∞ output voltage gain
**A _{V}**.

Figure 2