∆ CE Output impedance slope (iii) Transfer characteristic curve: I B vs I C ( V CE constant) • The collector-emitter voltage V CE is kept constant. • The base current I B is varied in steps of µA and the corresponding collector current I C is noted. • This is repeated by changing the value of V CE . The readings are tabulated.
• The transfer characteristics is a plot between the input current IB along x -axis and the output current I C along y -axis keeping V CE constant. • The slope of the transfer characteristics plot gives the current gain β can be calculated. XII- - ) XII- - ) - - - - PRACTICAL S.No V CE =1V V CE =2V I B (μA) I C (mA) I B (μA) I C (mA) I C (mA) I B (µA) ∆ I B ∆ I C Slope ∆ = ∆ Current gain = slope RESULT i) The input, output and transfer characteristics of the NPN junction in common emitter mode are drawn. ii) (a) Input impedance = (b) Output impedance = (c) Current gain β = (no unit) XII- - ) XII- - ) - - - - PRACTICAL AND Gate: Y=AB Y=AB SYMBOL PIN DIAGRAM-IC GND V CC IC TRUTH TABLE OR Gate: Y=A+B SYMBOL PIN DIAGRAM-IC TRUTH TABLE Y=A+B GND V CC IC