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Microstrip Impedance From Zo

Calculate the microstrip trace width required to achieve a target characteristic impedance.

Inverse microstrip calculator - computes the trace width needed to achieve a target characteristic impedance Zo, along with propagation delay, inductance, capacitance, and resistance per unit length.

Inputs

Target characteristic impedance in ohms (typically 50Ω or 75Ω)

Thickness of the PCB trace in millimetres

Thickness of the dielectric substrate in millimetres

Relative permittivity of the dielectric - FR4: ~4.5, Rogers 4003: ~3.55

Results

Target impedance must be greater than zero
Trace Width-mmRequired trace width in millimetres to achieve target impedance
Propagation Delay-ps/cmPropagation delay per centimetre in picoseconds
Inductance-nH/cmDistributed inductance per centimetre in nanohenries
Capacitance-pF/cmDistributed capacitance per centimetre in picofarads
Resistance-mΩ/cmDC resistance per centimetre in milliohms