Describe in your own words the characteristics of the ideal diode and how they determine the on and off states of the device. That is, describe why the short-circuit and open-circuit equivalents are appropriate.
Characteristics of an ideal diode are as follows:
• The ideal diode offers zero resistance when forward biased.
• The ideal diode offers infinite resistance when reverse biased.
When forward biased the region for the ideal diode drops to 0 V for any level of current. Hence, the ideal diode offers zero resistance when forward biased.
In the forward bias, the diode region has less resistance and thus ON state is established and leads to short circuit.
For the reverse biased case, the diode region has a very high resistance and thus the OFF state is established and the leads to open circuit.