Question

For a given transistor amplifier circuit in CE configuration V_CC = 1 V, R_c = 1 kΩ, R_b = 100 kΩ and β = 100. Value of base current I_b is

• A. I_b = 0.1 μΑ
• B. I_b = 10 μΑ
• C. I_b = 1.0 μΑ
• D. I_b = 100 μΑ

Answer 1

The Correct Option is B

Step 1: Find the collector current (\( I_C \)). The collector current (\( I_C \)) is determined by: \[ I_C = \frac{V_{CC}}{R_C}, \] where: - \( V_{CC} = 1 \, \text{V} \), - \( R_C = 1 \, \text{k}\Omega = 1000 \, \Omega \). Substitute the values: \[ I_C = \frac{1}{1000} = 1 \, \text{mA}. \] 
Step 2: Relate base current (\( I_B \)) and collector current (\( I_C \)). The current gain (\( \beta \)) of the transistor is given by: \[ \beta = \frac{I_C}{I_B}. \] Rearrange to solve for \( I_B \): \[ I_B = \frac{I_C}{\beta}. \] Substitute \( I_C = 1 \, \text{mA} = 10^{-3} \, \text{A} \) and \( \beta = 100 \): \[ I_B = \frac{10^{-3}}{100} = 10 \, \mu \text{A}. \] 
Final Answer: The base current is: \[ \boxed{I_B = 10 \, \mu \text{A}}. \]