Pulse and Digital Circuits

6.6 THE SATURATION PARAMETERS OF A TRANSISTOR AND THEIR VARIATION WITH TEMPERATURE

The output characteristics of n–p–n transistor having P_T = 250 mW at room temperature in the CE configuration are given in Fig. 6.36. The dc load line for R_L = 400 Ω is superimposed on the characteristics. However, from the characteristics in Fig. 6.36 the saturation voltage V_CE(sat) can not be found as its value is typically a fraction of a volt (0.1 V for Ge and 0.2 V for Si). A transistor is said to be in saturation when the emitter and collector diodes are forward-biased.

 

R_L = 400 Ω, V_CC = 10 V

To draw the dc load line:

V_CE(cut-off) = V_CC = 10 V

To be able ...