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.

Fundamental (V)

RMS amplitude of the fundamental tone.

Harmonics + Noise (V)

Total RMS residual of harmonics plus noise.

Compute THD+N percentage from the RMS residual and fundamental as thdnPercent = sqrt(harmonicsAndNoiseV^2) / fundamentalV * 100. 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]

THD+N (%)

THD+N ratio expressed as a percentage.

• Audio calculations must distinguish peak, RMS, dBu, dBV, acoustic SPL, electrical power, nominal impedance, sensitivity, and weighting. Loudspeaker impedance varies with frequency, room response changes SPL, and clipping or thermal limits are not represented by a single nominal value.
• 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 Total Harmonic Distortion

  Calculate THD from RMS harmonic amplitudes relative to the fundamental: sqrt(sum of harmonic squares)/fundamental. Output is percent and dBc; include only the harmonics specified by the measurement method, excluding noise and DC.

• THD Percent

  Compute total harmonic distortion in percent as 100 x sqrt(V2^2 + V3^2) / Vfundamental; harmonics must be non-negative and the fundamental positive.

• Phase Noise Integrated Jitter Simple

  Convert integrated single-sideband phase-noise power to RMS timing jitter with sqrt(2A)/(2πfcarrier); A is the dimensionless linear noise-to-carrier integral over the chosen offset band.