Question 246: Semiconductors and Logic Gates

Question

For a common emitter configuration, if $\alpha $ and $\beta $ have their usual meanings, the incorrect relationship between $\alpha $ and $\beta $ is :

Accepted Answer

We know, collector current is given as ${I_C} = \beta {I_B}$
Also, ${I_C} = \alpha {I_E}$
Ã¢ÂÂUsing, ${I_E} = {I_B} + {I_C}$
${{{I_C}} \over \alpha } = {{{I_C}} \over \beta } + {I_C}$
Solving above equations,
${1 \over \alpha } = {1 \over \beta } + 1$
$\alpha  = {\beta  \over {1 + \beta }}$

Answer

$\alpha  = {\beta  \over {1 + \beta }}$

Answer

$\alpha  = {{{\beta ^2}} \over {1 + {\beta ^2}}}$

Answer

${1 \over \alpha } = {1 \over \beta } + 1$

Answer

$\alpha  = {\beta  \over {1 - {\beta ^2}}}$

Semiconductors and Logic Gates

For a common emitter configuration, if \alpha and \beta have their usual meanings, the incorrect relationship between \alpha and \beta is :

Choose the correct answer: