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.

Mean centerline width (m)

Required number input.

Mean centerline height (m)

Required number input.

Estimate mean magnetic path length around a rectangular core centerline as 2(width+height). Use centerline dimensions, not external package dimensions; corners and air gaps are not corrected. 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]

Path Length M

The resulting path length m returned as a number.

• Inductor calculations depend on core material, air gap, turns, frequency, waveform, temperature, DC bias, copper resistance, skin and proximity effects, fringing, and saturation definition. Small-signal inductance and nominal current rating may not describe switching operation.
• 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.

• Magnetic Reluctance

  Calculate lumped magnetic reluctance ℛ=l/(μ₀μrA) for a uniform material segment. Use separate segments in series/parallel for mixed core and air-gap paths.

• Magnetic Air Gap Length

  Solve a simple magnetic-circuit inductance model for required air-gap length: lg=μ₀N²A/L−lc/μr. This treats fringing and leakage as negligible; a negative result means the requested inductance needs no positive gap under the model.

• PoE Delivered Power Budget

  Estimate delivered PoE power as source power minus I²R cable loss and other fixed losses. Use the full loop resistance of the powered conductor pairs; protocol class and startup margins are not modeled.