Question

In a CE transistor amplifier, the audio signal voltage across the collector resistance of2 kΩ is 2 V If the base resistance is 1 kΩ and the current amplification of the transistor is 100, the input signal voltage is

Options

• 0.1V

• 1.0V

• 1mV

• 10mV

Answer 1

10mV

Explanation:

The output voltage across the load R_C, V₀ = I_CR_C = 2

The collector current I_C = `2/(2 xx 10^3) = 10^-3"A"`

Current gain B = `("I"_"C")/("I"_"B") = 100`

IB = `("I"_"C")/100 = (10^-3)/100 =10^-5 "A"`

Input voltage V_i = I_BR_B = 1 × 10³ × 10⁻⁵

= 10⁻² V = 10mV