# hw05 - ECE 315 Homework 5 Due 11:15am Sept 28 2007 in the...

• Homework Help
• 1

This preview shows page 1. Sign up to view the full content.

ECE 315 Homework 5 Due 11:15am, Sept. 28, 2007, in the drop box 1. (BJT large-signal and small-signal characteristics in realistic designs) For a npn transistor in the forward active mode with emitter area A E =100 μ m 2 , N E = 10 20 cm -3 , N B = 10 17 cm -3 , N C =10 15 cm -3 , the base width W B =0.5 μ m, the emitter width W E =0.1 μ m, V bi =0.96V for the BE junction, the electron mobility μ n =1000cm 2 /Vs, the hole mobility μ p =400cm 2 /Vs, and the minority lifetime τ n = τ p =10 -7 s, (a) To evaluate the current at the BE junction (i.e., the emitter current I F0 ), what is the largest current component among electron/hole drift/diffusion in emitter/base (8 current components) and recombination in emitter/hole (two current components)? Briefly explain. (4 pts). (b) Find I F0 in the Ebers-Moll model (notice that this only needs to include the largest current component above. Please notice that this is a short-base diode case). (4 pts) (c) The base current contains two components: the recombination current and the hole back injection into emitter.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern