APD Multiplication Factor Calculator
Compute the avalanche photodiode multiplication factor from the Miller model M=1/[1-(V/Vb)^N]. Inputs are magnitudes: reverse-bias magnitude V≥0 V must remain below breakdown magnitude Vb>0 V (numerator V, denominator Vb; V=0 gives M=1, V→Vb- diverges). Exponent N in [1, 6] (default 2) captures the ionization coefficients. Signed voltages are not supported (use magnitudes). Result M≥1 is a dimensionless factor (per-carrier gain, not total current).
Description
Calculate APD avalanche multiplication below breakdown with the empirical Miller relation.
Compute the avalanche photodiode multiplication factor from the Miller model M=1/[1-(V/Vb)^N]. Inputs are magnitudes: reverse-bias magnitude V≥0 V must remain below breakdown magnitude Vb>0 V (numerator V, denominator Vb; V=0 gives M=1, V→Vb- diverges). Exponent N in [1, 6] (default 2) captures the ionization coefficients. Signed voltages are not supported (use magnitudes). Result M≥1 is a dimensionless factor (per-carrier gain, not total current).
When to use APD Multiplication Factor Calculator
- Calculate APD avalanche multiplication below breakdown with the empirical Miller relation.
- Compare fabrication or device scenarios while holding coefficients and unit conventions constant.
- Check a hand calculation before moving to a higher-fidelity process, circuit, or TCAD model.
How the calculation works
M equals one at zero reverse bias and diverges as the bias magnitude approaches breakdown from below.
M = 1 / [1 − (V/Vbr)^N] Interpreting the result
M equals one at zero reverse bias and diverges as the bias magnitude approaches breakdown from below.
Assumptions and limitations
- The Miller exponent is empirical; the model omits wavelength-dependent injection, excess noise, edge breakdown, and space-charge effects.
- Use parameters measured for the same material, geometry, temperature, and operating regime whenever the result informs engineering work.