Diode Characteristics

The Shockley equation describes the I–V curve:

$I_D = I_S \left(e^{V_D / (n V_T)} - 1\right)$

• $I_S$ — saturation current (picoamps or less for silicon),
• $n$ — ideality factor (1–2),
• $V_T \approx 25.9$ mV at room temperature.

Rule of thumb: the forward voltage rises about 60 mV ($n=1$) for every 10× increase in current, and falls about 2 mV/°C as temperature rises.

Key datasheet values: $V_F$ (forward voltage), $I_F$ (max forward current), $V_{RRM}$ (max repetitive reverse voltage), $I_R$ (reverse leakage) and $t_{rr}$ (reverse recovery time).