Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Avalanche multiplication

Required number input.

Hole-to-electron ionization ratio

Required number input.

Calculate electron-injection APD excess noise factor from gain and ionization-rate ratio using the McIntyre uniform-field model. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Excess noise factor

The resulting excess noise factor returned as a number.

• APD gain and excess-noise models depend on material, wavelength, bias, temperature, ionization ratio, bandwidth, and device construction. Operation near breakdown requires the manufacturer's limits and a complete noise and bias-stability analysis.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• ADC Quantization Error Bound

  Calculate the ideal rounding quantizer's maximum absolute error as half an ADC LSB. Assumes a uniform quantizer and input within the conversion range; offset, gain, and noise errors are excluded.

• APD Gain

  Calculate avalanche photodiode current multiplication from multiplied photocurrent and unity-gain primary photocurrent after dark-current subtraction.

• Finite-Gain Closed-Loop Error

  Calculate feedback closed-loop gain A/(1+Aβ) and percent error relative to ideal 1/β. Assumes negative feedback with positive real open-loop gain and feedback factor; frequency dependence is excluded.