An NPN BJT is biased so that its operating point lies at the boundary between active mode and saturation mode.
(a) Considering the Ebers-Moll of an NPN transistor. draw the simplified equivalent circuit for the transistor at the given operating point.
(b) Employing the simplified equivalent circuit of part (a), or working directly with Ebers-Moll equations.. obtain an expression for VEC at the specified operating point. Your answer should be in terms of 18 and the Ebers-Moll parameters.