The Impedance obtained using Zo is otherwise called as the single ended Zo, which occurs when testing a single line in microstrip which is not coupled to an adjacent line. Use the microstrip impedance calculator using Zo to calculate the Single ended impedance (Zo), propagation delay (Tpd), inductance (L), capacitance (C) and resistance (DC) using the trace width (w), trace thickness (t), dielectric thickness (h) and relative dielectric constant (er).