Why do we use ac model and dc model seperately for the diode to determine its total current?
Answers
Answer:
There is a lot of difference in the AC and the DC circuit analysis, the Ac circuit relies on higher voltages and the voltages are of different directions. Likewise after one develops a analog circuit, his first job is to check the BIAS of the circuit which is the DC networking.
If the circuit is designed and there is no signal given to it, then the AC analysis will be required to understand the frequency of the signals.
It is because of the capacitance at the junction.
Explanation:
When we forward biase diode then in DC model we consider the just forward resistance of the diode. But as when charges are separated by some distance, there occurs a capacitive effect. So, at depletion region due to this capacitive effect we connect a capacitor in parallel with the forward biase resistance. This forward biase resistance is also dependent upon frequency in case of AC, therefore we use AC and DC model separately to calculate total current.