Piecewise Linear Diode Model

[eximius]

Note: This is a past paper, I'm simply revising for an exam. But I thought that this was the best forum to stick it in.

Homework Statement

http://exampapers.cf.ac.uk/papers/engin/en1051/en1051a09.pdf [Broken]

Section A, Q1 c

[PLAIN]http://img684.imageshack.us/img684/9695/questionm.jpg [Broken]

Homework Equations

R1 = V1/I1
Rp = (V2-V1)/(I2-I1) = R1||R2
R2 = RpR1/(Rp-R1)

The Attempt at a Solution

R1 = 0.5/280x10-6 = 1785.71 ohms
Rp = (0.54 - 0.5) / (680x10-6 - 250x10-6) = 0.04 / 4x10-4 = 100ohms = R1||R2
R2 = RpR1/(Rp-R1) = 178571 / (-1685.71) = -105.9322185 = -105.93 ohms
V1 = 0.5V

Diagram -

[PLAIN]http://img407.imageshack.us/img407/4486/diagrame.jpg [Broken]

Forgive the wrong symbols, difficult with paint.

 

[Zryn]

That link:

A username and password are being requested by https://exampapers.cf.ac.uk [Broken]. The site says: "Enter your Cardiff University username & password"

Can you post the question rather than link to it please.

 

[eximius]

That link:



Can you post the question rather than link to it please.

Sorry I've fixed it.

 

[eximius]

Bump, sorry.