Shockley Diode Calculator: Analyze & Predict Diode Behavior

A Shockley Diode Calculator is a mathematical tool that facilitates the computation of various parameters in the Shockley Diode equation. The Shockley Diode Equation models the I-V characteristics (current-voltage relationship) of a diode. This calculator aids in the understanding and prediction of the diode behavior based on different input parameters.

This calculator is particularly useful in electronics and semiconductor physics, where diodes are frequently utilized. From the design of integrated circuits to power supplies, knowing the behavior of a diode is important to ensure proper functioning of electronic devices.


  • Medium: This represents the type of material used for the diode. It can be silicon, germanium, or other semiconductor materials. Each medium will have different properties which can affect the other parameters.
  • Emission Coefficient: Also known as the ideality factor or quality factor, this parameter describes how closely the diode follows the ideal I-V characteristic as defined by the Shockley diode equation. An ideal diode would have an emission coefficient of 1. However, real-world diodes will typically have an emission coefficient ranging from 1 to 2 due to non-idealities like recombination.
  • Saturation Current (mA): This is the reverse leakage current in the diode under the condition of reverse bias. It is denoted as I_s and is typically very small, in the range of microamps (µA) or nanoamps (nA) for silicon diodes.
  • Thermal Voltage (V): Also known as the volt-equivalent of temperature, it is given by the formula V_T = kT/q, where k is the Boltzmann's constant, T is the absolute temperature in Kelvin, and q is the elementary charge. At room temperature (approximately 300K), V_T is approximately 25.85 mV.
  • Voltage Drop (V): The amount of voltage that is reduced or "dropped" when current passes through the diode. It depends on the medium; for silicon diodes, it is typically about 0.7 V when the diode is forward-biased.
  • Current (mA): This is the current that passes through the diode. In the Shockley Diode Calculator, this could be an input or an output, depending on the other parameters provided.

Math Equations:

The fundamental equation used in a Shockley Diode Calculator is the Shockley Diode Equation:

I = I_s * (exp(V/(n*V_T)) - 1)


  • I is the diode current,
  • I_s is the saturation current,
  • V is the applied voltage,
  • n is the emission coefficient,
  • V_T is the thermal voltage.

This equation represents the I-V characteristics of a diode. By inputting different parameters into this equation via the calculator, users can analyze and predict the behavior of a diode under different conditions.


It is believed that these calculations are accurate, but not guaranteed. Use at your own risk!