Create a graph for me showing the current-voltage relationship of a PN junction diode, including both forward and reverse bias regions.

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This graph shows the current-voltage relationship of a PN junction diode. In the forward bias region, when voltage exceeds the turn-on voltage of approximately 0.7 volts for silicon, current increases exponentially. In the reverse bias region, only a very small reverse saturation current flows, typically in the microampere range. This asymmetric behavior makes diodes useful for rectification and signal processing applications. The behavior of a PN junction diode is described by the Shockley diode equation. This equation shows that current increases exponentially with voltage in the forward bias region. The equation includes I-S, which is the reverse saturation current, and V-T, the thermal voltage, which is approximately 26 millivolts at room temperature. In the reverse bias region, the current is approximately negative I-S, which is typically very small. This exponential relationship explains why the diode conducts significantly only after the threshold voltage is reached. When a large reverse voltage is applied to a PN junction diode, it eventually reaches the breakdown voltage. At this point, the reverse current increases dramatically. This breakdown occurs due to either the Zener effect in heavily doped diodes or the avalanche effect in lightly doped diodes. While regular diodes are not designed to operate in this region, special Zener diodes are specifically manufactured to work in the breakdown region with a well-defined breakdown voltage. This property makes Zener diodes useful for voltage regulation applications, where they maintain a constant voltage across their terminals despite changes in current. Temperature has a significant effect on diode characteristics. As temperature increases, the turn-on voltage decreases and the reverse saturation current increases. For silicon diodes, the turn-on voltage typically decreases by approximately 2 millivolts per degree Celsius increase in temperature. This is why the I-V curve shifts to the left at higher temperatures. This temperature sensitivity must be considered in circuit design, especially for applications where the diode operates near its threshold voltage or where the operating temperature varies significantly. Temperature compensation techniques are often employed in precision circuits to mitigate these effects. To summarize the current-voltage characteristics of a PN junction diode: Diodes conduct current primarily in one direction, which is the forward bias. In the forward bias region, current increases exponentially once the voltage exceeds the turn-on voltage, which is approximately 0.7 volts for silicon diodes. In the reverse bias region, only a small leakage current flows until the breakdown voltage is reached. The Shockley diode equation mathematically describes this I-V relationship. Temperature significantly affects diode behavior, with the turn-on voltage decreasing by approximately 2 millivolts per degree Celsius increase. These characteristics make diodes useful for various applications including rectification, signal demodulation, voltage regulation with Zener diodes, and overvoltage protection in electronic circuits.