ASSIGNMENT

Using your measurements for Figs. 1, 2, and 3, plot the output voltages, (Y axes), as a function of the input voltages, (X axes). On the same plots, show the outputs that would be expected in the crude and standard approximations. Use the data from the part 2 to compute the current flowing through the diode. This is the same as the current flowing through the 1 kΩ resistor, since there is no place else for that current to flow. The current through the 1 kΩ resistor may be computed, using Ohm’s law, from

I =(Vin-Vout)/1K Ω

Plot the current flowing through the diode (Y axis) as a function of the output voltage, which is the voltage across the diode (X axis). On the same plot show the current – voltage relationship expected in the standard approximation. What is the maximum voltage difference between your experimental data and the standard approximation?

Using the same data, compute the differential resistance of the diode from equation (3-2) by taking differences between successive data points for ∆V and ∆I. Plot the differential resistance (Y axis) as a function of the current (X axis) through the diode. The current used in this plot should be the average of the two successive values that form ∆I. For comparison, also plot equation (3-3) on the same graph. How does your plot of differential resistance compare with the theoretical approximation in equation (3-3)?