Biasing a diode. Part eh shows the diode as in figure 3.4 b except the depletion region is wider than in that figure. The left part of the diode, N region, is connected to the positive end of a battery. The negative end goes to a resistor, no value specified. The other end of the resistor goes to the right side of the diode, P region. There is a graph above the diode as in 3.4 b. The line of the graph begins on the left above zero. It increases to a peak just to the left of the junction. It quickly descends passing through zero at the junction. It continues to descend reaching a negative peak just to the right of the junction. It ascends slightly ending below zero. Part b shows a PN diode similar to figure 3.4 b except that the depletion region is not as wide. The left end of the diode connects to the negative end of a battery. The positive end connects to a resistor, value not given. The other end of the resistor connects to the right end of the diode. There is a graph above this diode. The curve starts out slightly below zero and rises, crossing zero to the left of the junction. It hits a peak also to the left of the junction which is about as high as it started below zero. It then crosses zero at the junction and reaches a negative peak to the right of the junction. It rises, crossing zero again and ends above zero. Part c has the battery connected the same as in part b. There is no depletion region, the electrons and holes are snuggled right up to the junction. The graph begins more negative than in part b and rises toward zero. It becomes nearly level close to the junction where it crosses zero. It continues upward getting more steep farther from the junction. It ends above zero and is higher than the graph in part b. End verbal description.
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