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.

Dielectric constant

Required number input.

Inner diameter

Required number input.

Outer diameter

Required number input.

Compute coaxial cable capacitance per meter as 24.1 x er / ln(d_outer/d_inner) with diameters in matching units. 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]

Capacitance per meter (pF/m)

The resulting capacitance per meter returned as a number.

• Capacitance, ESR, leakage, ripple rating, lifetime, and self-resonance vary with frequency, temperature, DC bias, aging, dielectric, package, and mounting. Nominal capacitance alone does not determine in-circuit impedance or reliability.
• 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.

• Coax L Per Meter

  Compute coaxial cable inductance per meter as 200 x ln(d_outer/d_inner) nH/m from the loop inductance mu_0/2pi x ln(b/a).

• CAN Bit Rate from Cable Delay

  Estimate a CAN bit-rate ceiling using cable length, one-way propagation delay per metre, transceiver delay, and the permitted propagation fraction of a bit. This is a timing-budget estimate, not a substitute for bit-timing analysis.

• CPW Impedance Approx

  Approximate coplanar waveguide impedance as (60 / sqrt(er_eff)) x ln(4 x a / b) with a = w/2 + gap and b = w/2; er_eff defaults to 4.