The junction diode model is a simple diode with an exponential characteristic. The diode formula essentially is:
f = Is*(exp(e/Vt) - 1)
However, if the exponent e/Vt reaches either an upper limit EMax or a lower limit Emin, the diode characterisic is linearly continued to avoid overflow or underflow, respectively.
Parameters: Is: Transport saturation current (default value = 1e-16 Amp) Vt: Thermal voltage (default value = 0.02585 Volt) EMin: Minimum exponent (default value = -100) EMax: Maximum exponent (default value = 40)