Diodivirtoja

Diodivirtoja, often referred to as diode current, represents the flow of electrical charge through a semiconductor diode. This flow is not a simple linear relationship with the applied voltage, unlike in a resistor. Instead, it is governed by the diode's unique characteristics, primarily its ability to conduct current in one direction (forward bias) while blocking it in the other (reverse bias).

In forward bias, when the voltage applied across the diode is positive and exceeds a certain threshold voltage, known as the turn-on voltage, the diode begins to conduct significant current. This current increases exponentially with further increases in forward voltage. The turn-on voltage is typically around 0.7 volts for silicon diodes and 0.3 volts for germanium diodes.

In reverse bias, when the voltage applied across the diode is negative, the diode ideally allows very little current to flow. This is because the applied electric field opposes the movement of charge carriers, creating a depletion region within the semiconductor that acts as an insulator. A very small leakage current does exist, but it is usually negligible for most practical applications. However, if the reverse voltage becomes too large, exceeding the diode's breakdown voltage, a phenomenon called avalanche breakdown or Zener breakdown can occur, leading to a sharp increase in reverse current and potentially damaging the diode. The relationship between voltage and current in a diode is described by the Shockley diode equation.