a)Explain in no more than 300 words the difference between the large and the small signal models for a Bipolar Junction Transistor (BJT). Explain why the operating point in l-V

characteristics of BJT plays a central role in determination of a signal model. Can this determination be done without the operating point? b)Draw a schematic of the p-n-p Bipolar Junction Transistor (BJT) fabricated on a silicon substrate as a part of an integrated circuit. Explain your choice of the particularly doped silicon substrate and the order of fabrication steps in an eventual fabrication flow for the p-n-p BJT. Draw a schematic of so-called Cascode Amplifier and explain how this configuration is related to the three circuit configurations (namely a common-base, a common-emitter,and a common-collector) for a Bipolar Junction Transistor (BJT) to act as an amplifier.Write a comparison of the Cascode Amplifier configuration with respect to the three common configurations with respect to: the voltage gain, the current gain, and the power gain.(6 marks7 d)Describe three applications of the Bipolar-CMOS-DMOS (BCD) power transistor of your choice in a custom chip. Write an essay of no longer than 300 words justifying why the BCD power transistor is an optimal solution for each of the three chip applications selected.