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Shockley Diode Calculator.

Calculate ideal diode current using the Shockley equation with explicit device and temperature inputs.

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01

Set your values

Results update as you type.

Diode current: 0.01201 A

Diode current

0.000000A
Thermal voltage: 0.025852 V

Thermal voltage

0.000000V

Results update automatically as you type.

Educational idealized model with every parameter shown; this tool does not size wiring, components, or safety systems.

Use Cases

Circuit design and analysis

Engineers use the Shockley equation to estimate diode current for given voltage, temperature, and device parameters, aiding in circuit simulation and design.

Example: Determine the forward current of a 1N4148 diode at 0.7 V and 300 K with Is=2.52 nA and n=1.9.

Educational demonstrations

Students and educators can explore how diode current varies with voltage, temperature, and ideality factor, reinforcing semiconductor physics concepts.

Example: Plot I-V curves for different ideality factors to see the effect on turn-on voltage.

Frequently Asked Questions

What is the Shockley diode equation?
The Shockley diode equation models the current-voltage relationship of an ideal diode: I = Is * (exp(V/(n*Vt)) - 1), where Vt = k*T/q (thermal voltage). It depends on saturation current (Is), ideality factor (n), temperature (T), and applied voltage (V).
How does temperature affect diode current?
Temperature appears in the thermal voltage Vt = k*T/q. Higher temperature increases Vt, which reduces the exponential sensitivity to voltage, but also increases the saturation current (if modeled separately). This calculator uses the temperature you input to compute Vt.
What is the ideality factor?
The ideality factor (n) accounts for deviation from ideal behavior. It is typically between 1 and 2 for real diodes. n=1 for ideal, n=2 for some LEDs or high-level recombination. This calculator lets you set n explicitly.

Tips & Common Mistakes

Tips

  • Ensure the saturation current is in amperes (A) and temperature in kelvins (K) for accurate results.
  • For silicon diodes, typical ideality factors range from 1 to 2; check datasheets for exact values.
  • Remember that the Shockley equation assumes an ideal diode; real diodes have series resistance and leakage effects not modeled here.
  • Use the calculator to compare how changing temperature affects the diode's forward voltage drop at a given current.

Common Mistakes to Avoid

  • Using Celsius instead of kelvin for temperature; always convert to kelvin (K = °C + 273.15).
  • Forgetting to include the ideality factor, which can significantly alter the calculated current.
  • Assuming the saturation current is constant with temperature; in reality, it varies strongly with temperature.

Last updated: August 13, 2026