Shockley diode equation
The Shockley diode equation, or the diode law, named after transistor co-inventor William Shockley of Bell Labs, models the exponential current–voltage (I–V) relationship of semiconductor diodes in moderate constant current forward bias or reverse bias: I D = I S ( e V D n V T − 1 ) , {\displaystyle I_{\text{D}}=I_{\text{S}}\left(e^{\frac {V_{\text{D}}}{nV_{\text{T}}}}-1\right),} where I D {\displaystyle I_{\text{D}}} is the diode current, I S {\displaystyle I_{\text{S}}} is the reverse-bias saturation current (or scale current), V D {\displaystyle V_{\text{D}}} is the voltage across the diode, V T {\displaystyle V_{\text{T}}} is the thermal voltage, and n {\displaystyle n} is the ideality factor, also known as the quality factor, emission coefficient, or the material constant. The equation is called the Shockley ideal diode equation when the ideality factor n {\displaystyle n} equals 1, thus n {\displaystyle n} is sometimes omitted.