# RF Wireless World

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## Photodiode Cutoff Wavelength | Definition, equation, calculator

This page describes Photodiode Cutoff Wavelength definition. It mentions Photodiode Cutoff Wavelength equation/formula and Photodiode Cutoff Wavelength calculator.

Definition: To build up leakage current in the photodiode, the energy of the photon must be taken greater than or equal to the energy band gap between the valance and conduction band called band gap (Eg).
➨ h*v > = Eg
h*c/λ > = Eg or λ < = h*c/Eg

So the threshold for the conduction or detection, is commonly called as the long wavelength cutoff point (λc).
λc = h*c/Eg

### Photodiode Responsivity Calculator

Energy Gap in eV (Input) :

Cutoff Wavelength in nm (Output):

Example of Photodiode Responsivity calculator:
INPUTS : Eg = 1.42 eV
OUTPUTS: λ = 873.23 nm

### Photodiode Cutoff Wavelength Equation | Photodiode Cutoff Wavelength Formula

Following equation or formula is used for Photodiode Cutoff Wavelength calculator. ### Useful converters and calculators

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