signal integrity

Microstrip PCB Impedance

Computes four key per-unit-length parameters of a microstrip PCB trace: characteristic impedance, capacitance, effective propagation delay, and inductance using standard IPC-2141 approximation formulas.

Inputs

Relative Permittivity

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

Height of Dielectric(mm)

Height of the dielectric substrate in millimetres

Width of Trace(mm)

Width of the PCB trace in millimetres

Trace Thickness(mm)

Thickness of the PCB trace in millimetres

Results

Characteristic Impedance125.37ΩCharacteristic impedance in ohms

Capacitance Per Unit Length4.454e-11F/mDistributed capacitance per unit length in farads per metre

Effective Propagation Delay5.882e-9s/mEffective propagation delay per metre in seconds

Inductance Per Unit Length7.000e-7H/mDistributed inductance per unit length in henries per metre