Question

The input characteristics of a transistor in $CE$ mode is the graph obtained by plotting

• A. $I_{B}$ against $V_{BE}$ at constant $V_{CE}$
• B. $I_{B}$ against $V_{CE}$ at constant $V_{BE}$
• C. $I_{B}$ against $I_{C}$ at constant $V_{CE}$
• D. $I_{B}$ against $I_{C}$ at constant $V_{BE}$

Answer 1

Answer: (A)

$I_{B}$ against $V_{BE}$ at constant $V_{CE}$

Answer 2

Input characteristics curve is drawn between base current $I_{B}$ and emitter base voltage $V_{R B}$ at constant collector emitter voltage $V_{C B}$ Dynamic input resistance,
$R_{i}=\left(\frac{\Delta V_{B E}}{\Delta I_{B}}\right)_{V_{C E}}=\text { constant }$